Clepsydra NTS-3000, NTS-5000, NTS-4000 User Manual

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USER MANUAL

NTP/PTP Network Time Servers

NTS-3000 NTS-4000

NTS-5000 w/ 4x PTP/IEEE1588

multi LAN HYDRA-Extender

Updated: September 2017

SAFETY INSTUCTIONS! 3! TRADEMARKS, ACKNOWLEGMENT & CONTACTS! 3!

QUICK!MANUAL! 5!

1.! QUICK!INFO!–!ABOUT!PRODUCT! 6!

2.! QUICK!INFO!–!PRODUCT!AT!ARRIVAL! 7!

3.! QUICK!INFO!–!MOUNTING!AND!CONNECTING! 8!

4.! QUICK!INFO!–!POWERING!ON! 9!

5.! QUICK!INFO!–!PANEL!KEYBOARD!SETUP! 12!

6.! QUICK!INFO!-!LCD!MESSAGES! 14!

7.! QUICK!INFO!–!TROUBLESHOOTING!WITH!SSH! 15!

8.! QUICK!INFO!–!UPDATING!FIRMWARE! 17!

9.! MAIN!MANUAL! 18!

10.! PRODUCT PERFORMANCE! 19!

11.! PRODUCT ASSURANCE REQUIREMENTS! 26!

12.! NTS-X000 FIRMWARE EVOLUTION! 28!

13.! GLOSSARY TIME TERMS! 29!

14.! OVERVIEW! 31!

15.! HARDWARE! 32!

16.! EXTRA!FEATURES! 36!

17.! HIGH!PRECISION![NS]!4XPTP!ITU-I!G.8261! 38!

18.! HYDRA!MODULAR!MULTI-LAN!EXTENSION! 39!

19.! UTC,!LEAP!SECOND!AND!TIME!MULTISOURCE! 41! .!!!!!!!!!!UTC! 41! .!!!!!!!!!!GPS!TIME!(GPST)! 41! .!!!!!!!!!!GLONASS!TIME!(GLONASST)! 42! .!!!!!!!!!!GALILEO!TIME!(GST)! 42! .!!!!!!!!!!BEIDOU!TIME!(BDT)! 42! .!!!!!!!!!!LEAP!SECOND! 43!

20.! GNSS!RECEIVER!&!ANTENNA! 49!

21.! NTS-PROTECT!(EXTRA!SURGE!PROTECTION)! 56!

22.! FO-CONVERTER!(FIBER!OPTIC!CONVERTER)! 61!

23.! ROBUST!SYNC!-!APPLICATION!NOTES! 64!

24.! POWERING!UP! 66!

25.! LCD!MESSAGES! 67!

26.! KEYBOARD!SETUP! 68!

27.! RESTORING!FACTORY!DEFAULTS! 69!

28.! UTC!MULTISOURCE!INPUTS!OF!NTS! 70!

29.! MAINTAINING!HOLDOVER!MODE!(NTS-5000)! 71!

30.! SOFTWARE!SETUP!FOR!STD.!LAN1-LAN2! 73!

31.! PTPV2!SETUP!OF!PTP1-LAN4!(LAN3-LAN6)! 81!

32.! APPLICATION!NOTES!FOR!HFT!&!MIFID!II! 100!

33.! SOFTWARE!SETUP!VIA!WWW!(HTTP/HTTPS)! 103!

34.! NTP!SYMMETRIC!AUTHENTICATION!(MD5)! 113!

35.! SYSLOG! 121!

SAFETY INSTUCTIONS

ATTANTION!

These are the important Safety Instructions that should be followed during installation and maintenance of the Elproma NTS-3000/4000/5000 timeserver family product.

IMPORTANT NOTE

This equipment contains hazardous AC and DC voltages. Do not handle any metallic part until the power has been disconnected. Do not assemble, disassemble set when the power is ON. Making wiring and touching cables is strongly prohibited when power is ON. Please refer to your RACK’19 safety instruction to learn more about connecting power to equipment. The NTS-protection system requires PE line to be connected into RACK’19 din rails.

Elproma safety advises:

1. Safety first! Never work alone under hazardous voltage conditions

2. High short circuit current trough conductive materials can cause server burns

3. Check that the power cord(s), plug(s), and sockets are in good conditions

4. Always use qualified service personnel to install permanently wired equipment

5. Do not handle any metallic part before the power has been disconnected

6. Take care your power lines and rack’19 frame is properly PE grounded

TRADEMARKS, ACKNOWLEGMENT & CONTACTS

ELPROMA Electronics Poland Sp. z o.o.

Szymanowskiego Str. 13 PL05092 Lomianki/Warsaw POLAND (EU)

Phone: +48 227517680 Fax: +48 227517681

Internet: http://www.clepsydratime.com

E-mail: info@clepsydratime.com

Acronyms

1PPS!

1!Pulse!Per!Second!

ITU!

International!Telecom!Union!

AIV!

Assembly,!Integration!and!Validation!!

KPI!

Key!Performance!Indicator!

BIPM!

Bureau!International!des!Poids!et! Mesures!

MCT!

Modular!Coherent!Transfer!

CA!

Certificate!Authority!!

NMI!

National!Metrological!Institutes!

CCTF!

Consultative!Committee!for!Time!and! Frequency!

NTA!

National!Time!Authority! (mostly!the!same!as!NMI)!

CIF!

Core!Infrastructure!Facilities!!

NTP!

Network!Time!Protocol!

COTS!

Commercial!Off-the-Shelf!!

OFT!

Optical!Fibber!Technology!

CV!

Common!View!

OSC!

Oscillators!(OCXO,!Rubidium,!Cs)!

DAB!

Digital!Audio!Broadcasting!

PPP!

Point!Precise!Positioning!

DEMETRA!

Demonstrator!for!EGNSS!services! based!on!Time!Reference!Architecture!

PTP! PTPv2!

Precise!Time!Protocol!IEEE!1588! (WR!–White!Rabbit!profile!of!PTP)!

DB!

Database!(mostly!SQL)!

QR!

Quality!Report!

DVB!

Digital!Video!Broadcasting!

RINEX!

Receiver!Independent!Exchange! Format!

ETH!

Ethernet!

RMO!!

Regional!Metrological! Organization!

EBU!

European!Broadcast!Union!

SFN!

Single!Frequency!Network!

EGNOS!

European!geostationary!navigation! overlay!system!

SIS!

Signal!In!Space!

EGNSS!

European!GNSS!

SPF!

Service!Provision!Facility!

EURAMET!

European!Regional!Metrological! Organisation!!

SV! SVN!

Satellite!Vehicle! Satellite!Vehicle!Number!

EWR!

Extended!White!Rabbit!

SVF!

Service!Validation!Facility!!

FO!

Fibber!Optic!

SW!

Software!

FR!

FREE-RUN!mode!!

T&F!

Time!and(&)!Frequency!

GCC!

Galileo!Control!Centre!

TAI!

International!Atomic!Time!!

FTP!

File!Transfer!Protocol!

TA(PL)!

Polish!Atomic!Time!

GDO!

GPS!Disciplined!Oscillator!

TDMA!

Time!Division!Multiple!Access!

GGTO!

Galileo!GPS!Time!Offset!

TFL!

Time!and!Frequency!Laboratory!

GMT!

Greenwich!Mean!Time!

TLC!

Time!Local!Clock!!!!!(the!same!as! UT)!

GNSS!

Global!Navigation!Satellite!System!

TMC!

Time!Master!Clock!(see!TSG)!

GPS!

Global!Positioning!System!

TRF!

Time!Reference!Facility!(see!TMC)!

GPST!

GPS!Time!Scale!

TSA!

Time!Stamping!Authority!

GSA!

GNSS!Supervising!Authority!

TSI!

Time!Service!Infrastructures!

GST!

Galileo!System!Time!

TWSTF!

Two!Way!Satellite!Time!and! Frequency!Transfer!

HTTP! HTTPS!

Hypertext!Transfer!Protocol!!! Hypertext!Transfer!Protocol!Secure!!!!

UT!

User!Terminal!(see!also!TLC)!

HO!

HOLDOVER!mode!!

UTC!

Universal!Time!Coordinated!

HW!

Hardware!

WP!

Work!Package!

IPR!

Intellectual!Property!Rights!

WR!

White!Rabbit!(see!PTP)!

IRIG-B!

Time!Code!(AM!or!DM)!!

WPL!

Work!Package!Leader!

QUICK!MANUAL!!

Configure In 5 Minutes

1. QUICK!INFO!–!About!product

NTS-x000 covers following ELPROMA time server models: NTS-3000, NTS-4000, NTS-5000. These

are all STRATUM-1 NTP time servers. They optionally support other standards too, incl. PTP/IEEE1588, IRIG, IBM SYSPLEX etc. The main difference between specific models is built-in oscillator (OSC). It serves time & frequency even when NTS-x000 cannot receive GNSS signals. This is called HOLDOVER mode (HO). NTS-x000 operating in HO mode reminds STRATUM-1. However, to operate HO server OSC must be synchronized to GNSS first, and this means NTS-x000 must get synchronized to GNSS first too. Unsynchronized OSC works in FREE-RUN (FR) mode and server claim then STRATUM-6. Server NTS-5000 optionally supports low level hardware PHY timestamping. It can be equipped with 1-4 high accuracy (PDV) PTP/IEEE1588 cards offering nanoseconds [ns]. Servers supports simultaneously several UTC ref. sources of time from 3 independent groups:

#Group: Ref. TIME:

1) GNSS satellite systems GPS, GLONASS, GALIELO, BEIDOU

2) Remote TIME SERVERS NTP, PTP/IEEE1588:2008, IBM SYSPLEX, IRIG-B

3) Local ATOMIC clock s 1PPS, 10MHz, RS-232, RS-485, IRIG-B, LAN/VLAN/WAN

NTS-x000 (NTS-3000, NTS-4000, NTS-5000) can simultaneously use multiple REF. TIME

ELPROMA Time Server computes weighted average time from its all trusted TIME ref. sources.

2. QUICK!INFO!–!Product!at!arrival

Standard product pack includes on arrival inside box:

Network Time Server NTP/PTP NTS-3000, 4000 or 5000 model

1pcs.

Intelligent GNSS Receiver w/ build in Antenna

1pcs.

Roof Mounting Kit (H=05m) (incl. screws, handlers etc.)

1set.

CD with software Incl. PDF manual

1pcs.

Ethernet patchcord UTP cat. 5 (2m)

2pcs.

110-230VAC Power cable 1.5m

1pcs.

Shipment can include extra parts (product extra options):

2nd Redundant GNSS Receiver (see p.2 in table above)

extra 1pcs.

Mounting accessories (if option a. delivered)

extra 1set.

Please ref. to p.3 above

NTS-protect surge/overvoltage for: GNSS, 110-230 PwR, ETH 1&2

1set.

NTS-FO (converter electric-2-fibber) e.g. to connect GNSS

2pcs. (1set)

Important Note!

Antenna cable is not included. Standard UTP cat 5 (or above) is recommended min. - best if

external env. use. You can connect GNSS receiver on max. distance of 0.7km from server, and without amplifying signal. However, it is much better to choose STP (shielded) cat. 6 cables. It much more resistant for EMC interferences. Using STP a max. connection distance is also doubled (1.4km).

PTP/IEEE1588 1GE Ethernet 1-4 modules are always arriving build-in to NTS-5000 (if option ordered)

3. QUICK!INFO!–!Mounting!and!connecting!

Quick unpacking/mounting steps:

1. Remove all parts from shipped BOX. Prepare additional tools: RJ45 connectors (pcs.2), UTC or STP cat.5 (not included to shipment), Ethernet crimping tool, screwdriver, scissors etc.

2. Mount GNSS receiver on the top point of roof of a building. It should access possible a 360o sky view to receive max. available satellite vehicles (SVN). Do not mount GNSS receiver nearby: wall, chimney, electric engines, fans and airconditions. The min. recommended distance to keep between other: GNSS, TELECOM transmitters at least 2 meters!

3. Lunch UTP (STP) cables down to server room. Cables should not be located in direct neighborhood of other power lines. Try play gently with cables (do not cut cables, nor break cable). Well done cable installation should be tested for connectivity and resistance before using.

4. (optionally) Mount NTS-surge protection on the back of rack’19 shell. Ensure, it is properly grounded to PE lines. Ask, certified authority to assist you, if you are not qualified for electric installations. Read all safety instructions first.

5. Crimp RJ45 connectors to terminate antenna cables. Test connection again.

6. Locate Time Server in rack”19 shell. Please keep min. 1U space to neighborhood product that can unexpectedly hit your NTS-x000.

7. Connect all POWER lines 110-230VA.

8. Switch POWER-ON. Observe server’s LCD and 6x LED during BOOT, and GNSS synchronization.

9. Setup basic LAN configuration from front panel KEYBOARD.

10. Prepare PC for SSH/www advance setup via interface LAN1 or LAN2.

Rack”19 shell with 3x NTS-5000

(Installation example)

4. QUICK!INFO!–!Powering!ON!!

If both, GNSS antenna and the PWR lines have been connected to NTS-x000, unit is ready to use.

You can TURN-ON a power switch located on the back panel of NTS-x000 server. In case of redundant power lines (A/B), each power supply should be SWITCH-ON separately in random order.

The YELLO LED starts pulse (PPS) max. 1 minute after switching power-ON. This is typical firmware start-up time duration. takes 1 minute. BOOT progress and each phase of starting process can be traced on front panel 6x LED (left side) and LCD display located on right side of front panel.

Following boot sequence presents start-up phases of NTS-x000 (NTS-3000, NTS-4000, NTS-5000):

Process

Time

duration

6x LED

(Front Panel - left)

LCD display

(Front Panel right side)

ANT1/ANT2

(Back Panel)

OFF-ON

Yellow LED is OFF

INIT 1s

Yellow LED is OFF

INIT 1s

Yellow LED is OFF

Boot Loader V16.0120 Loading

10!

# Time

duration

6x LED

(Front Panel - left)

LCD display

(Front Panel right side)

ANT1/ANT2

(Back Panel)

BOOT

LOADER

<1min

(60s)

Yellow LED is OFF

INIT

<5s

Yellow LED is OFF

READY

<2s

Yellow LED is OFF

NET INIT

<2s

GNSS RECEIVEING IF

YELLO LED PULSE 1PPS

Yellow LED pulse

NTP

READY

LAN

Link(-)

+1min

(+60s)

Yellow LED pulse

GNSS

READY

+6min

(+360s)

max

ToD (NMEA) millisecond accuracy

of synchronization begins now

Yellow LED pulse

1PPS

READY

+6min

(+360s)

max

Microsecond [us] to nanosecond [ns]

high accuracy of 1 PPS

synchronization has started now

Yellow LED pulse

Press & hold [OK] to enter setup

Press & hold [OK] [C] to reset to defaults

LAN1: no carrier

LAN2: no carrier!

Loading NTS-5000

15-07-2017 INIT

17:17:37 SAT A=0/0!

15-07-2017 OK

17:17:37 SAT A=0/0!

15-07-2017 OK

17:17:37 SAT A=17/30!

15-07-2017 OK

17:18:47 SAT A=19/30!

11!

Process

Time

duration

6x LED

(Front Panel - left)

LCD display

(Front Panel right side)

ANT1/ANT2

(Back Panel)

IRIG

READY

+2min

(+180s)

max

Yellow LED pulse

OSC

READY

+10min (+600s)

max

Yellow LED pulse

ETH

Link(+)

LAN1

LAN2

Yellow LED pulse

Remarks:

a. STEP #1 - STEP #6 should terminate success (please observe step by step as presented in

above table). If no back panel (ANT1/ANT2) YELLOW LED pulsing, please re-check hardware installation incl. GNSS receiver, cables, connectors etc. You wi ll b e sti ll a bl e to LO G-IN (SSH/WWW) to server, but it will only work FREE-RUN mode STRATUM-6 for LAN1/LAN2.

b. STEP#7. If no GNSS signal receiving until now, the NTS-x000 starts internally search for

alternative primary ref. of UTC time. This can be remote NTP server, or any external clocks serving UTC and connected by RS232/RS485, IRIG-B, or SYSPLEX. Unless you have any of them active (a remote NTP servers must be defined in NTS-x000 setup first) your NTS-x000 will remind in FREE-RUN mode (STRATUM-6) since it still misses a ref. of UTC time.

c. STEP #7 to STEP#9. At least 5 satellites must be found to synchronize ToD ( Time of a Day)

from GNSS. The #volume of visible satellite vehicles (SV) can be traced on front panel LCD. The detailed strength of SV signals can be traced using WWW/SSH setup only.

d. STEP #10 A Pulse Per Second (1PPS) synchronization starts here. STEP#10 is only reached

if ToD (STEP #9) synchronization is successfully pending. The 1PPS synchronization is high accurate one. It offers from level of microsecond [us] down to nanosecond [ns] level of synchronization accuracy. At the same time, a To D information provides limited millisecond [ms] accuracy of synchronization only. This is also a moment, the internal built-in OSC (OCXO, Rubidium) are beginning to be synchronized (PLL) preparing HOLDOVER mode. It will take at least another 10-20 minutes until built-in OSC will be ready for HO. HOLDOVER status is indicated by LED an explained at STEP#12.

e. STEP #11 indicates once IRIG-B microprocessor module has started and operational READY.

If all data correctly is received form GNSS the following below LCD screen is displayed for ANT1 (A) and/or ANT2 (B). Information also provides detailed information for each GNSS subsystem: GPS, GLONASS, BEIDOU, GALILEO (id supported for your region):

15-07-2017 OK

23:01:00 SAT A= 18/32!

15-07-2017 OK

23:01:00 SAT B= 16/32!

15-07-2017 OK

17:18:47 SAT A=19/30!

15-07-2017 OK

17:18:47 SAT A=19/30!

15-07-2017 OK

17:18:47 SAT A=19/30!

12!

5. QUICK!INFO!–!Panel!Keyboard!SETUP!

Switch ON power and a following screen sequence will appear on LCD display:

When booting the following message will be displayed while dots will be counted up booting progress in the lower line:

After approximately 1 minute the following sequence of messages are displayed in loop:

Press & hold front panel KEYBOARD [OK-key] for 5s to entrance SETUP. The LAN1 IP address will appear on LCD. Use arrow keys [çè] to select column position, and [éê] to assign requested 0-9 values for each IP address position separately.

Press [OK] to switch to next screen (or press & hold [OK] for 5s to save entered configuration). You can always interrupt and quit SETUP at any moment by pressing & holding [C]. Exiting SETUP in [C] (CANCEL) mode disregards all changes and last saved settings will be restored. Repeat above sequences to setup LAN2 IP address:

Important note! Both LAN1 & LAN2 are information isolated (not routed) and therefore they can serve different TCP/IP sub-networks, both theoretically with independent GATEWAY. However, due to fact they share single IP stack, it is strongly not recommended to set both GATEWAYS simultaneously! This problem is well known for FreeBSD UNIX – a NTS-x000 firmware basis on. Instead, please consider using static routing option in main MENU available text mode via SSH. If you need to use 2 different GATEWAYS please set single LAN (#1 or #2) and leave another one filled by zero digits (000.000.000.000). Once IP address is set following screen request your confirmation to save all settings:

Loading NTS-5000

Press & hold [OK] to enter setup

Press & hold [OK] [C] to reset to defaults

LAN1: no carrier

LAN2: no carrier!

LAN1: (disabled)

LAN2: (disabled)!!

LAN1 IP address:

192.168.001.002!

LAN1 netmask:

255.255.255.000

LAN1 gateway:

192.168.001.001

LAN2 IP address:

010.000.000.002!

LAN2 netmask:

255.255.000.000

LAN2 gateway:

010.000.000.001

Boot Loader V16.0120 Loading

13!

and your NTS-5000 timeservers is ready to communicate via LAN1/LAN2 interface. Unless you wish to provide more advance settings, the above configuration is minimum required to start working.

If the GNSS (GPS/Glonass/Galileo/Beidou) Multi-SAT receiver remains asynchronous the following information will be displayed on LCD indicating a part of process called – “warm” start:

Once number of satellites are in view receiver lock to GNSS and synchronization process is pending. Starting from now your server is READY and following message is displayed:

If you use 2 receivers (A & B), additional information from Multi-SAT GNSS (B) will be displayed too:

It is possible and very probable both GNSS receivers can show different volume of GNSS satellites.

In standard operation mode above screen is displayed to present each satellite system data using format: XX/YY where XX are number of visible satellites for specific system; YY - total #amount of available SAT channels at receiver). Following additional information can be provided at any time:

Environmental DATA is provided periodically using time zone settings:

Plugging Ethernet cable to LAN1 will trigger Link(+) and following message will be displayed on LCD:

Are you sure?

[OK] - Yes [C ancel] - No!

15-07-2017 INIT

23:00:11!

15-07-2017 OK

23:01:00 SAT A= 18/32!

15-07-2017 OK

23:01:01 SAT B= 19/32!

15-07-2017 GPS 11/32

23:01:17 GNSS 9/32!

Firmware release

NTS-3000 04/02/2014!

Firmware release

NTS-4000 09/03/2015!

Firmware release

NTS-5000 05/03/2016!

CPU temperature [C]

+41.5 +36.8 +25.1!

Onboard voltage [V]

+3.32 +5.03 +15.54!

CPU temperature [F] +106,7 +98,2 +77,1

LAN1: active

LAN2: no carrier!

LAN1: 192.168.1.2

LAN2: (disabled)!

LAN1: no carrier

LAN2: no carrier!

14!

6. QUICK!INFO!-!LCD!Messages!

If no antenna is currently connected to NTS-x000 device, a following error screen will be shown:

Error: all antennas disconnected

NTS-x000 server is requiring min. 5 satellites in order to get time from GNSS (e.g. GPS). If it receives less than 5 satellites or if quality of signals is not good enough, server can display following message:

Error: missing GNSS satellites

and it automatically switch to HOLDOVER or FREE-RUN mode. modes time server. In HOLDOVER mode, a time is not provided from GNSS but from built-in oscillator OSC (OXCO – NTS-4000, Rubidium & OSCO – NTS-5000). Std. NTS-3000 does not include oscillator therefore it HOLDOVER is limited to very short time and basis on built-in QURTZ. To provide accurate time in HOLDOVER mode, oscillators must be synchronized to GNSS first. If server has never reached synchronization to GNSS it reminds in FreeRUN mode operating STRATUM-6. It can then provide a precise time, but not accurate to UTC. In case of poor SV signal quality, the following LCD message can be displayed:

Error: bad GNSS geometry (min 5 sat)

This require find a better GNSS antenna location otherwise NTS servers cannot obtain time information from GNSS antenna. The unit will still work properly in HOLDOVER (if previously synchronized to GNSS long enough), otherwise operate FREE-RUN mode not synchronized and providing large offset ERROR.

The LCD shows only a status of the GNSS antennas. It does not show status of the other time sources as I/O time interfaces (1PPS, IRIG-B etc.). However other time sources can be monitored and traced by a remote software utility ntpq. The ntpq is available via SSH/WWW setp.

There another error message “Err sync” is possible to be displayed. It indicates that internal phase/frequency loop is not yet locked or temporary not working, because of 1PPS jitter or too much offset from GPS time. Details of problem can be investigated using ntpq via SSH/WWW setup.

Error: GNSS is not in sync

Last possible error message is “Error call service” message. It means that device is not operating properly (message will show up approx. 30 sec after rebooting). Please contact service in this situation for further instructions.

Error: Device out of order

15-07-2017 ERRsats 23:35:21 ANT ERROR

15-07-2017 ERRsats 23:38:28sat A=1/12

15-07-2017 ERRsats 23:45:55sat A=1/12

17-02-2014 ERRsync 8:02:21 sat A=5/12

Error call service +48 (22) 7517680

15!

7. QUICK!INFO!–!Troubleshooting!with!SSH!

If any steps earlier were not succeeding, or there are any doubts regarding GNSS signal receiving, antenna connection quality and so forth, problem can only be investigated via software SETUP. Unless “Error call service +48 (22) 7517680” message is displayed on LCD, you should be able to login to server using any networking PC/ Laptop, and SSH protocol (default ENABLE). Operating systems, the one such as Linux, Unix, Mac OS/X - they all include SSH. For Microsoft Windows, you can download FREE putty.exe from http://www.putty.org/.

To run SHH communication connect your PC/laptop to LAN1 or LAN2 of NTS server. Please do not use LAN3-LAN6 for SSH communication. The factory default setting (user and password) is:

Username: admin

Password: 12345

For diagnostic go to MISC section, select GPS option, and observe strength of SAT signals. You should be able to observer at least min. 5 satellites to be able synchronize to GNSS (e.g. GPS).

16!

If connection to GNNS receiver is OK, you should see screen similar to above examples. If values of SAT signal strength are zero (00) it means GNSS receiver is not receiving SAT signals from antenna. Please recheck hardware installation (step by step again), and restart server and observe LCD and LEDs. It is also a good idea to select NTPQ menu item at MISC menu level.

If antennas is installed correct, the REACH column should not be zero (0). After several minutes of server being uptime this octal value should reach number 377. It means GNSS data receive is correct and server can start synchronizing local holdover oscillators, in order: OCXO, and after 10-20 minutes Rubidium (Rb) too. A HOLDOVER oscillator is ready if NTPQ “pe” command displays apteryx ‘*’ or letter ‘o’ located at very first column of a table. Server will operate FreeRUN mode of oscillator, if GNSS signal quality is poor or nor receiving. In this case OCXO (Rubidium), will not get mark of ‘*’ or letter ‘o’ located at very first column of a table. Please refer to more NTPQ commands.

17!

8. QUICK!INFO!–!Updating!FIRMWARE!!

Time Server firmware update can arrive neither on USD-memory or it can be downloaded via cryptographically protected CLOUD. User access to cloud is available on request.

1. Prepare USB flash drive with minimum 128Mb free space (FAT32 formatted)

2. Download nts345.v-yymmdd.img file from cloud and copy it to root folder of USB flash drive

3. Plug-in to NTS-x000 front panel USB connector (upper or lower)

4. Login to NTS-x000 using SSH and LAN1 or LAN2

5. Go to MISC menu, and select UPGRADE submenu using arrow-keys

6. Follow information on the screen

7. Once firmware update is done, please EXIT (LOGOUT) and restart server OFF-ON again

8. New firmware version should be displayed on LCD after restarting

Server SETUP via SSH (display view)

Front Panel LCD information

Firmware release

NTS-5000 06/03/2017!

18!

9. MAIN!MANUAL!!

User Manual

19!

10. Product Performance

Time Servers NTS-3000/4000/5000 achieves following accuracy:

• 32-channel MultisSAT receiver to UTC: <15x 10E-9s [ns] (nanosecond)

• Interface LAN1, LAN2 accuracy NTP: <100x 10E-3s [ms] (millisecond)

• Interface LAN1, LAN2 accuracy PTP: <10x 10E-3s [ms] (millisecond)

• Interface LAN3-LAN6 accuracy PTP* (HW stamps): <25x 10E-9s [ns] (nanosecond)

• IRIG-B sync accuracy <10x 10E-6s [us] (microseconds)

• NTP over Internet typically better than 100 [ms] (milliseconds)

Below screenshot presents typical synchronization of NTS-x000 after min. 1 hour uptime:

View of internal NTS-3000 clocks (single GPS receiver). Accuracy over LAN is claimed to be 28[us]

NTS-3000/4000/5000 product performance has been measured by NMI (International Institutes of Metrology). ELPROMA cooperates to several EU Institutes who regularly test our product.

In years 2015-2016 ELPROMA servers has been updated by technology developed during EU project DEMETRA (www.demetratime.eu). ELPROMA servers has been tested in below schemes:

1PPS in (reference)

1PPS”

OFFSET

1PPS’ (1PPS” - 1PPS’)

Internal offset measurement. NTS-3000 generates 1PPS” output that is compared to ref. input signal. Offset measurement is provide by hardware precise clock counter (PikTime T3200 counter).

Hardware LAN accuracy measurement scheme:

1PPSin

OFFSET

(1PPS” - 1PPS’)

Time Server

LAN$

Time Server

1PPS”!

1PPS’!

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Elproma servers has been tested in following Metrology LAB’s

1) Laboratory!SHORT-LOOP-TEST!based!on!national!UTC!(k)!and!in!cooperation!to:!!

• INRIM!(Italy)!! based!on!“Project!DEMETRA”!(www.demetratime.eu)!!

• GUM!(Poland)!! based!on!“Project!DEMETRA”!(www.demetratime.eu)!

• NPL!(UK)! based!on!“Project!DEMETRA”!(www.demetratime.eu)!

• SIQ!(Slovenia)!!!!!

• VLS!(The!Netherlands)!regarding!direct!cesium!(CS)!clock!synchronization!

General$scheme$of$Short-Loop$Test$(SMF$sends$all$data$to$Database)$

Short-Loop$Test$Campaign$for$ELPROMA$unit$(UT$with$NTS-x000)$

21!

2) END-TO-END!with!participation!of!selected!End-users!and!NTA!based!on!ref.!Galileo!or!GPS!UTC!signals!!

General$scheme$of$END-TO-END$Test$(SMF$sends$all$data$to$Database)$

End-to-End$Test$Campaign$for$ELPROMA$unit$(UT$with$NTS-x000)$

All synchronization data is stored in database and can be review retrospectively for future analyses.

22!

23!

24!

25!

NTS-5000HFT January 2017 tests at London NPL has confirmed following performance for PTP/IEEE1588:2008:

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11. Product Assurance Requirements

The Product Assurance (PA) and Safety program is implemented and performed by Elproma and its subcontractors to assure the compliance. It bases on ISO 9001 Number (AT-11895) audited by auditors from Quality Austria (since 2011). PA covers regulations and procedures covering all projects during: design development, manufacturing, integration, and acceptance. The PA is structured according to the standard disciplines required for international IQNet ISO9001 programs and it regularly audited to appoint its international standards. In particular, the PA Program has following tasks:

• assure and verify that performance and quality requirements are properly fulfilled by the design of products,

• assure that the design and development processes are compliant with the QA requirements, and related ISO9001 procedures,

• give evidence of the procedures, reports of audits,

• apply the necessary control during throughout the Design, Manufacturing, Assembly,

Integration and Qualification/Acceptance Testing for the achievement of the required quality level.

ISO9001:2008$Certificate$

Elproma shall allocate a PA manager to its own related tasks. Elproma has performed ISO9001 external audits to check our ready for product assurance. The ISO9001 and IQNet audits were hosted by Quality Austria in March/April 2015 and successfully terminated. Therefore, the certification is valid until April the 6th 2018.

27!

28!

12. NTS-x000 Firmware Evolution

First NTS-3000 was developed in 1999. Since begin product base on Open Source FreeBSD Unix (available on BSD license). The NTS-5000 was developed in 2004, and NTS-4000 arrived in 2007.

Very important functionality and security updates has been added to all product as a result of DEMETRA Horizon 2020 program. Newest technology is now available (since 2017).

Since 1999, there were 7 generation of products. The internal hardware architecture of NTS family product has been modified 3 times, but still there is 100% compatibility between specific generations of product at external application level. The LAN1 & LAN2 are still the same I/O since 1999 and they warranty 100% compatibility to product made since 1999. The LAN3 of models manufactured 19992004 has been cancelled and replaced by new generation high speed LAN3-LAN6 interfaces supporting PTP/IEEE1588:2008 – all modern profiles.

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13. Glossary Time Terms

In alphabetic order:

Accuracy - The degree of conformity of a measured or calculated value to its definition or with respect

to a standard reference time. In the meaning of NTP (Network Time Protocol) the accuracy determines how close the PC clock is to UTC reference (GNSS or external atomic clock).

Atomic Time Scale (TA) - a time scale based on atomic or molecular resonance phenomena. Elapsed

time is measured by counting cycles of a frequency locked to an atomic or molecular transition. Earlier time scales were based on the rotational rate of the earth.

GBEIDOU– (see COMPASS)

Calibration - The process of identifying and measuring time or frequency errors, offsets, or deviations

of a clock/oscillator relative to an established standard, such as UTC(NIST).

Clock - a device for maintaining and displaying time.

GOMPASS (BEIDOU)– is Chinese satellite navigation system. It consists of two separate satellite

constellations – a limited test system that has been operating since 2000, and a full-scale global navigation system that is currently under construction. The first BeiDou system, officially called the BeiDou Satellite Navigation Experimental System.

Coordinated Universal Time (UTC) - a coordinated time scale, maintained by the Bureau International

des Poids et Mesures (BIPM), which forms the basis of a coordinated dissemination of standard frequencies and time signals. A UTC clock has the same rate as a Temps Atomique International (TAI) clock or international atomic time clock but differs by an integral number of seconds called leap seconds. The UTC scale is adjusted by the insertion or deletion of leap seconds to ensure approximate agreement with UT1.

Drift (frequency) - the linear (first-order) component of a systematic change in frequency of an

oscillator over time.

Frequency - the rate at which a periodic phenomenon occurs over time. Frequency drift - see drift. Frequency offset - the frequency difference between the measured value and the defined value. Frequency shift - change in frequency from a standard reference. Frequency stability - statistical

estimate of the frequency fluctuations of a signal over a given time interval.

Frequency standard - an oscillator such as a rubidium (Rb), cesium (Cs), or hydrogen (H) maser

who’s output is used as a frequency.

GALILEO – is a global navigation satellite system (GNSS) currently being built by the European Union

(EU) and European Space Agency (ESA). One of the aims of Galileo is to provide a high-precision positioning system upon which European nations can rely, independently from the Russian GLONASS, US GPS, and Chinese COMPASS (BEIDOU) which can be disabled in times of war or conflict. Galileo is compatible to US GPS (see GPS).

GLONASS – acronym for Globalnaya navigatsionnaya sputnikovaya sistema or Global Navigation

Satellite System, is a space-based satellite navigation system operated by the Russian Aerospace Defence Forces. It provides an alternative to Global Positioning System (GPS) and is the only alternative navigational system in operation with global coverage and of comparable precision. Glonass use L1-1575.42MHz with additional frequency margin between 1597.50-1609.50Mhz.

GPS (Global Positioning System) - a highly accurate, global satellite navigation system based on a

constellation of at 24 satellites orbiting the earth at a very high altitude 20000 km. GPS signals are: L1-1575.42MHz;L2-1227.6MHz;L3-1381.05 MHz

GMT (Greenwich Mean Time) - a 24 Hour system based on mean solar time plus 12 hours at

Greenwich, England. Greenwich Mean Time can be considered approximately equivalent to Coordinated Universal Time (UTC), which is broadcast from all standard time and frequency radio stations. However, GMT is now obsolete and has been replaced by UTC.

International Atomic Time (TAI) - an atomic time scale based on data from a worldwide set of atomic

clocks. It is the internationally agreed upon time reference conforming to the definition of the second, the fundamental unit of atomic time in the International System of Units (SI). It is defined as the

30!

duration of 9 192 631 770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium - 133 atom.

Synchronization - The process of measuring the difference in time of two time scales such as the

output signals generated by two clocks. In the context of timing, synchronization means to bring two clocks or data streams into phase so that their difference is 0 (see time scales in synchronism).

Synchronization - Relative adjustment of two frequency sources with the purpose of canceling their

frequency difference but not necessarily their phase difference.

Stability (frequency) - statistical estimate of the frequency fluctuations of a signal over a given time

interval: Long term stability usually involves measurement averages beyond 100s. Short term stability usually involves measurement averages from a few tenths of a second to 100s.

Stratum - indicates how fare from cesium ref. the clock is in the chain of synchronization.

Time code - a system of symbols (digital or analog) used for identifying specific instants of time. An

information format used to convey time information. IRIG-B is example of Time Code.

Time interval - The duration between two instants read on the same time scale.

Time scale - a system of unambiguous ordering of events. A time scale is meant to be stable and

homogeneous.

Time standard - a continuously operated device used for the realization of a time scale in accordance

with the definition of the second and with an appropriately chosen origin.

Time step - a discontinuity in a time scale at some instant. A step is positive (+) if the time scale

reading is increased and negative (-) if the reading is decreased at that instant.

Difference between Accuracy and Stability in Time Synchronization

ACCURATE & PRECISE PRECISE BUT NOT ACCURATE NOT ACCURTE & NOT PRECISE DRIFT

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14. Overview!

This manual is common for all Clepsydra Time server models available from Elproma: NTS-3000, NTS-4000 and NTS-5000 also shortly indicated as NTS-3000/4000/5000. Therefore, it use following convention of NTS-4000/5000 to present functionality what us not available for NTS-3000. Unless it is clearly indicated in the manual the assuming for functionality is valid for all 3 above models.

The NTS-3000/4000/5000 Clepsydra Time Server provides a high precision time directly to TCP/IP Ethernet networks using: NTP (Network Time Protocol), SNTP (Simple Network Time Protocol). It is compatible to all available versions of NTP/SNTP available on market. Optionally NTS-4000/5000 servers can extra support PTPv2 (Precision Time Protocol IEEE1588), IRIG-B and IBM SYSPLEX synchronization standards in configuration depends on ordered options.

The NTS-3000/4000/5000 supports all majority of current popular operating systems (OS) including:

Microsoft Windows, Mac OS/X, Linux, FreeBSD, HPUX, IBM AIX, IBM AS/400, ORACLE SUN, CISCO

and other UNIX family systems. It can synchronize simultaneously ten of thousands servers, workstations, routers, telecom stations (BTS), industrial and power distributions controllers.

Standard product provides accurate time via 2xLAN ports. Optionally the configuration can be extended up to 6xLAN both: 100Base-T and GE. The Fiber Optic (FO) Ethernet communiocation is possible via special converter available separatelly.

The NTS-4000/5000 has several extra I/O synchronization standards including optionally interface for: IRIG-B, 1PPS, 10MHz, SYSPLEX, PTPv2/IEEE1588, E1/T1. Special fast sync startup mode of NTP has been implemented to reduce unsynchronized time after powering up products that has no battery powered up RTC clocks. Server NTS-5000 can be extra equipped with additional 8x IRIG-B (AM) output distribution panel.

The accurate target UTC time is calculated as weighted average of numerous time sources including double A/B redundant GNSS (GPS/Glonass/Galileo) receiver with build-in active antenna. Servers NTS4000/5000 can use external clocks as reference too. The target UTC time is produced on way of comparing settings of maximum available time references including: GNSS, 1PPS, 10Mhz, IRIG-B, SYSPLEX etc. Special DCF77 RF-AM receiver is available on request for Central Europe & Germany.

Unit status information can be traced on front panel 2x20 characters LCD display. More detailed statistic is available by remote NTP software utilities (ntpq, ntpdc) and setup utility via: WWW, TELNET, SSH, SNMP.

All Clepsydra Time Servers can operate in standard or special NTP authentication mode protected by MD5 algorithms and PKI infrastructure. Unit supports broadcast, manycast, multicast and client/server modes of NTP. A true novelty is an option to create cascade of servers where one ca n simul ate an NMEA (GPS) antenna for the other. This functionality enables time synchronization of secured LANs with official time from NTP servers available publicly on line in Internet.

All servers are ready to work with any external SYSLOG or SNMP (MIB2) server. Error messages can be traced on local (2x20) LCD or remotely over wall LED NTP display from Elproma. It let friendly warn on any unexpected situation that may happen. Messages can be also sent via E-MAIL directly from any NTS-3000/4000/5000 timeservers.

Servers are designed to operate without ventilators and fans. Metal housing is an important part of natural cooling system designed in such way that unit can be located in the neighbourhood of any device working inside rack19 mount frame.

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15. Hardware!

NTS-3000/4000/5000 (standard version) has similar front panel architecture and components location. There is 2x20 characters LCD Status Display (green color). All devices come with 6-key keyboard for quick setup. The RS232 (DSUB-9 mail) connector is preserved for value added functionality (e.g. cesium clock connection etc.). There is 2xUSB2.0 interface for firmware upgrade or backup purpose. There is LAN2 connector located on the front panel too. It contains 2x LEDs: green - indicates cable connection, yellow - flashes while data is being transmitted.

Standard Front Panel

The back panel of NTS-3000/4000/5000 (standard version) is organized on way there are several I/O referential time sections. :

Standard Back Panel

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NTS-3000 (Standard Version)

NTS-3000 (standard) Front Panel

NTS-3000 (standard) Back Panel

Table describe connectors it’s availability and related into it functions:

Name

Connector

Standard

Purpose

Availability

Antenna (A)

RJ-45

RS-485

Antenna connector (main antenna)

Antenna (B)

RJ-45

RS-485

Antenna connector (backup antenna)

IRIG-B IN*

BNC

IRIG-B

IRIG-B source signal (optionally)

IRIG-OUT*

BNC

IRIG-B

IRIG-B output signal (optionally)

10 MHz

BNC

10MHz

10 MHz output reference signal

1 PPS IN

BNC

1pps

1 PPS (pulse per second) source signal

1 PPS OUT

BNC

1pps

1 PPS (pulse per second) output signal

TIMER IN

DSUB9

RS-232

2xPPS (pulse per second) input signal

TIMER OUT

DSUB9

Variou s

Extra feature (not available yet)

LAN1

RJ-45

TCP/IP

Local Area Network (back panel)

LAN2

RJ-45

TCP/IP

Local Area Network (front panel)

RS-232

DSUB9

RS-232

For technical and service purpose

USB

KUSB

USB

For technical and service purpose

NTS-3000 (standard) Back Panel picture

NTS-3000 (standard) Front Panel picture

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NTS-4000 OCXO (Standard Version)

NTS-4000 OCXO (Standard Version) 1U rack’19 mount Front Panel

NTS-4000 OCXO (Standard Version) Back Pane

Table describe connectors it’s availability and related into it functions:

Name

Connector

Standard

Purpose

Availability

Antenna (A)

RJ-45

RS-485

Antenna connector (main antenna)

Antenna (B)

RJ-45

RS-485

Antenna connector (backup antenna)

IRIG-B IN

BNC

IRIG-B

IRIG-B source signal (optionally)

IRIG-OUT

BNC

IRIG-B

IRIG-B output signal (optionally)

10 MHz

BNC

10MHz

10 MHz output reference signal

1 PPS IN

BNC

1pps

1 PPS (pulse per second) source signal

1 PPS OUT

BNC

1pps

1 PPS (pulse per second) output signal

TIMER IN

DSUB9

RS-232

2xPPS (pulse per second) input signal

TIMER OUT

DSUB9

Variou s

Extra feature (not available yet)

LAN1

RJ-45

TCP/IP

Local Area Network (back panel)

LAN2

RJ-45

TCP/IP

Local Area Network (front panel)

RS-232

DSUB9

RS-232

For technical and service purpose

USB

KUSB

USB

For technical and service purpose

NTS-4000 OCXO (Standard Version) Back Panel picture

NTS-4000 (Standard Version) Front Panel picture

35!

NTS-5000 Rubidium+OCXO (Standard Version)

NTS-5000 RUBIDIUM+OCXO (Standard Version) 2U rack’19 mount Front Panel

NTS-5000 RUBIDIUM+OCXO (Standard Version) 2U rack’19 mount Back Panel

Table describe connectors it’s availability and related into it functions:

Name

Connector

Standard

Purpose

Availability

Antenna (A)

RJ-45

RS-485

Antenna connector (main antenna)

Antenna (B)

RJ-45

RS-485

Antenna connector (backup antenna)

IRIG-B IN

BNC

IRIG-B

IRIG-B source signal (optionally)

IRIG-OUT

BNC

IRIG-B

IRIG-B output signal (optionally)

10 MHz

BNC

10MHz

10 MHz output reference signal

1 PPS IN

BNC

1pps

1 PPS (pulse per second) source signal

1 PPS OUT

BNC

1pps

1 PPS (pulse per second) output signal

TIMER IN

DSUB9

RS-232

2xPPS (pulse per second) input signal

TIMER OUT

DSUB9

Variou s

Extra feature (not available yet)

LAN1

RJ-45

TCP/IP

Local Area Network (back panel)

LAN2

RJ-45

TCP/IP

Local Area Network (front panel)

RS-232

DSUB9

RS-232

For technical and service purpose

USB

KUSB

USB

For technical and service purpose

NTS-5000 RUBIDIUM+OCXO (Standard Version) 2U rack’19 mount Front Panel

NTS-5000 RUBIDIUM+OCXO (Standard Version) 2U rack’19 mount Back Panel

36!

16. Extra!Features

Extra options and product extensions can make a difference to std. panel component location:

Double Redundant Power Supply

Custom NTS-3000 or NTS-4000ocxo with redundant A+B dual power supply

Custom NTS-5000 Rb+OCXO with redundant A+B dual power supply

Direct Cesium 5071A (Custom) Time Server

Custom NTS-3000 with special direct cesium 5071A interface (1PPS+RS232)

Dial-Up GSM/PSTN/ISDN Time Server

Custom NTS-3000 Dial-Up with built-in GSM & PSTN (or ISDN) modem

6xLAN (NTP) Time Server

Custom NTS-3000 with 6x LAN (NTP) interfaces /also available as NTS-4000/

Custom NTS-5000 Rb+OCXO with 6x LAN (NTP) interfaces

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Low performance PTP Master Clock

NTS-4000OCXO PTPv2 Master Clock (IEEE1588 Server on LAN5)

NTS-5000 Rb+OCXO PTPv2 Grand Master Clock (IEEE1588 Server on LAN5)

IEEE15888/PTPv2 Slave Clock with E1/T1 outputs

NTS-4000OCXO PTPv2 Slave Clock (IEEE1588 Client on LAN4) with T1/E1 outputs

NTS-5000Rb+OCXO PTPv2 Slave Clock (IEEE1588 Client on LAN4) with T1/E1 outputs

IEEE15888/PTPv2 Grand Master Clock with E1/T1 (SSU) in/out

NTS-4000OCXO Grand Master PTPv2 Clock (LAN4 PTP-client LAN-5-PTP-server) with T1/E1 in/out

NTS-5000Rb+OCXO Grand Master PTPv2 Clock (LAN4 PTP-client LAN-5-PTP-server) with T1/E1 in/out

8x IRIG-B DISTRIBUTION SYNCHRONIZED TO 2x OPTO GNSS RECEIVER

NTS-5000Rb+OCXO w/ 8x IRIG-B output & 2x OPTO GNSS antenna

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17. High!Precision![ns]!4xPTP!ITU-I!G.8261!

This!is!extra!option.!The!upper-floor!can!support!max.!4x!PTPv2/IEEE1588:2008!w/!SyncE.!Each!card!is!equipped!

with!2x!1GE!Ethernet!interfaces,!but!only!1!of!2!can!be!used!in!time .!Su pp o rted!conne ctors!are:!SFT,!RJ45.!!

The!best!benefit!of!using! 4x!PTP!cards! is! security! and! ultra-high!synchronization!accuracy.!Each! card! has!own! IPv4!stack,! and! id! driven!by! own!operating! system!OS!(Unix!family).! Cards! are!information!isolated! from! each!

other! and! from! GrandMaster! part! of! NTS-5000.! The! PTPv2! together! with! SyncE! offers! nanosecond! level! of! synchronization.!They!also!support!SNTP!(Simple!Network! Time ! P rotocol)!server!that!is!100%!compatible!to!std.!

NTP!clients.!

NTS-5000Rb+OCXO w/ extra 4x PTP modules (SFT+RJ45) – all PTP modules works autonomous with own TCP/IP stack

Double redundant Power Supply, and dual redundant GNSS receivers (ANT1, ANT2)

NTS-5000Rb+OCXO w/ extra 3x PTP modules (SFT+RJ45) – all PTP modules works autonomous with own TCP/IP stack

Double redundant Power Supply, and dual redundant GNSS receivers (ANT1, ANT2)

NTS-5000Rb+OCXO w/ extra 2x PTP modules (SFT+RJ45) – all PTP modules works autonomous with own TCP/IP stack

Double redundant Power Supply, and dual redundant GNSS receivers (ANT1, ANT2)

NTS-5000Rb+OCXO w/ extra 2x PTP modules (SFT+RJ45) – all PTP modules works autonomous with own TCP/IP stack

Double redundant Power Supply, and dual redundant GNSS receivers (ANT1, ANT2)

39!

18. HYDRA!Modular!Multi-LAN!Extension!

This is extra option. Each NTS-x000 (incl. NTS-3000, NTS-4000, NTS-5000) can be linked with a special multi-LAN extender, the NTS-HYDRA. Extender is a separate unit. It is equipped with own CPU and it can support up to 7 independent network interface cards (NIC). Unit is Linux driven, therefore all 7 NIC shares single IP stack for NTP/PTP operations. There are 3 types of NIC available: 1GE (1,2,4x LAN/NIC), 10GE (1 or 2x LAN/NIC), 100GE (1x LAN/NIC). Supported connectors are: SFT or RJ45.

HYDRA extender can support max. 7 NIC, 4x LAN/NIC. Together with preinstalled 2x LAN 1GE, single extender supports max. 30x LAN – each different configuration. There are max. 10x HYDRA extenders, so all together cluster supports max. 300x LAN’s in single UTC distribution node. HYDRA clusters are useful to create synchronization time scale clusters.

NTS-3000 and NTS-4000 HYDRA extension

40!

NTS-5000 HYDRA w/ 4x PTP High Precision LAN3-LAN6 Interfaces

HYDRA super-cluster with max. 10 extenders (all together max. 300 LAN interfaces 1GE, 10GE, 100GE)

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19. UTC,!Leap!Second!and!Time!Multisource!

.!!!!!!!!!!UTC!!

The basic supported time scale is UTC. Customized version of servers can be configured to supply other scales including TAI and GPST (a separate scale supporting GPS satellite system). Universal Coordinated (UTC) Time is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time (GMT) set according to astronomic observations. For most purposes, UTC is synonymous with GMT, but GMT is no longer precisely defined by the scientific and IT community, therefore we strongly suggest to not mismatch both names.

The UTC time is computed by NTS-x000 satellite receiver. There are max. 2 receivers supporting each of NTS-x000. They support GNSS (GPS, GLONASS, BEIDOU, GALILEO). The final time is computed UTC is weighted average of all sat systems. Therefore, ELPROMA systems are not as much sensitive to internal errors of specific satellite systems as other product available on market.

GNSS Systems strongly rely on measuring the time of arrival of radio signals propagation down on Earth. Thus, each GNSS System has its own time reference from which all elements of the Space, Control and User segments are time synchronized. The most relevant GNSS time references used for computing UTC are briefly described below:

.!!!!!!!!!!GPS!Time!(GPST)!

GPS Time (GPST) is a continuous time scale (no leap seconds) defined by the GPS Control segment on the basis of a set of atomic clocks at the Monitor Stations and onboard the satellites. It starts at 0h UTC (midnight) of January 5th to 6th 1980 (6.d0). At that epoch, the difference TAI−UTC was 19 seconds, thence GPS−UTC=n − 19s. GPS time is synchronized with the UTC(USNO) at 1 microsecond level (modulo one second), but actually is kept within 25 ns.

42!

.!!!!!!!!!!GLONASS!Time!(GLONASST)!

GLONASS Time (GLONASST) is generated by the GLONASS Central Synchronizer and the difference between the UTC(SU) and GLONASST should not exceed 1 millisecond plus three hours

(i.e., , where ),

but is typically better than 1 microsecond. Note: Unlike GPS, Galileo or BeiDou, GLONASS time scale implements leap seconds, like UTC.

.!!!!!!!!!!GALILEO!Time!(GST)!

Galileo System Time (GST) is a continuous time scale maintained by the Galileo Central Segment and synchronized with TAI (atomic timescale) with a nominal offset below 50 ns. The GST start epoch is 0h UTC on Sunday, 22 August 1999 (midnight between 21 and 22 August).

.!!!!!!!!!!BEIDOU!Time!(BDT)!

BeiDou Time (BDT) is a continuous time scale starting at 0h UTC on January 1st, 2006 and is synchronized with UTC within 100 ns< (modulo one second).

Below diagram presents offsets between specific GNSS satellite systems:

43!

.!!!!!!!!!!LEAP!Second!!

A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time, and UT1 time. Without such a correction, time reckoned by Earth's rotation drifts away from atomic time (TAI) because of irregularities in the Earth's rate of rotation. Since this system of correction was implemented in 1972, the 37 leap seconds have been already inserted, the most recent on 31st of December 2017 23:59:60 UTC-midnight. Together with first 10 initial seconds’ total amount of leap seconds is now 37s, and therefore the formula for calculating is:

TAI – UTC = 37s (01 January 2017)

Adding leap second procedure bases on special announcement NTP flag set by decoding special message file from NIST or IERST. The implementation procedure theoretically should give a perfect 60 second and the UTC time clock effect should show as follow:

23:59:59 -> 23:59:60 -> 00:00:00

But there are a couple o problems why above structure needs an attention during IT system deployment. According to D. Mills article “A kernel model for precision timekeeping”, there are possible several side effects of getting time deviations depends on end-user operating system (OS) and its kernel version. We would like to point attention to possible several scenarios of supporting leap second depends on OS version and its kernel (e.g. those implemented in old API generation POSIX Linux system but not only limited to). Possible implementations of leap second support at OS kernel are:

1. Step OS Clock Time Back at the End of the Leap Second

Leap Second - Step Back Clock at the End of Second

In this case time is simply stepped back at the end of an inserted leap second as shown in above figure. Therefore, OS time cannot be monotonic, and thus duplicate time stamps occur after the leap second (e.g. at the beginning of the next UTC day). Mills claims as a result, there can be later time stamps assigned to events which occurred earlier, which can heavily mess up applications using time stamps to order the sequence of events or transactions.

44!

2. Step OS Clock Time Back at the Beginning of the Leap Second

Leap Second Time Back at the Beginning of Second

Time is simply stepped back at the beginning of an inserted leap second as shown above. In this case time is also not monotonic. Mills points the difference from the previous case is that duplicate time stamps occur during the leap second, i.e., at the end of the UTC day. Similarly, there can be later time stamps assigned to events which occurred earlier, which can cause the same confusion as the previous case.

3. Stopping OS Clock Time Counting for Exactly One Second

Leap Second Stopping Clock Time for 1 Second

A modified approach which guarantees strictly monotonic time stamps has been proposed Mills, the inventor of the Network Time Protocol (NTP), who suggested stopping the clock during an inserted leap second, but incrementing the fractions of time stamps by the smallest possible time increment whenever the time is read by an application. This technique gives another the 4th minor scenario (see below). Some operating systems like Microsoft Windows are not aware of leap second and thus are not prepared to handle it. In such case it may be possible to slew the system time over the leap second.

45!

Windows slows the system clock down to half the nominal speed for 2 seconds, so the Windows OS time is again aligned to UTC. This method is not optimal, but at least after the leap second the OS time is correct again. Nevertheless, there is an important conclusion going out of above discussion. Depends on OS version and its kernel, the leap second can be supported on different ways giving offset error to UTC for seconds, and in some cased for hours. Many vendors therefore recommend to not use synchronization a couple of hours before and after leap second UTC midnight.

Dave Mills NTP proposal to Increment Time LSB

OS clock is just put on hold for one second as shown above and time stamps are all the same during the inserted leap second. OS time does not increase monotonically, and time stamps can't be used to order events.

A true nove lty is real multi source time concept. Product can take simultaneously a reference time from its all-available hardware inputs. Compering to other existing solutions, it does not take “artificial selected” source of UTC, but it is automatically and continuously computing weighted average UTC clock ERROR from available sources (clock truechimers) including:

• GNSS satellite systems (GPS, GLONASS, GALIELO, BEIDOU via: RS485 or LAN)

• Remote TIME SERVERS (NTP, PTP/IEEE1588, SYSPLEX))

• Local external atomic clocks (IRIG-B, 1PPS, 10MHz, RS-232),

46!

Multisource concept. Server simultaneously receives time from all available time sources

• GNSS satellite systems (GPS, GLONASS, GALIELO, BEIDOU via: RS485 or LAN)

• Remote TIME SERVERS (NTP, PTP/IEEE1588, SYSPLEX))

• Local external atomic clocks (IRIG-B, 1PPS, 10MHz, RS-232),

Some other vendor products available on market use name “multisource” too. The following figure presents difference between ELPROMA-Clepsydra multisource meanings and other concepts:

Other product available on market Ref. time is taken from” the best” available UTC and corrected

(Switching between “best selected” sources) by weighted arithmetic mean ERROR of all clocks 1-3

sydra Time Servers does not allow manual source time selection, however single source can be achieved by disabling all remind sources. This is including GNSS Multi-SAT receiver supporting GPS, GLONASS, GALILEO, BEIDOU – each acting independent source for UTC time. Considering other than std. configuration please take a note that modern time metrology highlights philosophical rule where “having single clock you have to trust it; taking time from 2 different clocks - you don’t know what time is; 3 or more clocks enables to consider what time might be”.

True output UTC time (single s ource syste m)

For single reference source of time (i.e. GPS), the synchronization and output UTC is represented:

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Single source of reference UTC time

The dispersion represents the maximum possible error on the offset of source time reference like GPS. The current Timeserver time is represented by zero (0) offset. The “Offset” margin adjustment of internal server’s clock is proceeding and it can be set to possible values between “Reference UTC” plus “Dispersion” and the “Reference UTC” minus “Dispersion”. In case of single source servers the target UTC accuracy can be then less or equal to it’s reference origin pattern. However using single source of time avoids advance computing for target output UTC. Actually timeserver always provides “best replica” of source reference parameters. In some cases like Institutes of Metrology this technique can be very useful, especially when using local-external, high performance atomic clock - as primary reference source of time. Using local atomic clocks let produce high accuracy and stable UTC output for NTP/PTP.

Single source configuration of NTS-3000 connected to Cesium Primary Reference Std. 5071A Clock

To allow output UTC (clock) quickly achieve high accuracy, yet avoid overshooting the time with large time adjustments, timeserver uses large adjustments (after power-up) occur quickly and small adjustments occur over time for normal mode of operation. For small time differences (less than 128 ms) server uses a minimal-gradual adjustment. This is called slewing. For larger time differences (i.e after powering up), the adjustment is immediate and large. This is called stepping. The different types of time adjustment are shown in figure below.

Computing target output UTC time from multisource NTS-3000/4000/5000. Step adjustment is possible after Power-ON only.

Output UTC time from multisource time reference

For multisource the synchronization and output UTC is much more complicated. Several steps are involved by NTS-3000/4000/5000 in determining the correct time on server’s inputs. Although some of these steps are not necessary when synchronizing to a single source (i.e. GPS) it is essential for more complex multisource.

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Multi source reference of UTC

Increasing the number of independent reference UTC sources is good for two reasons: it allows for more accurate output time, and reduces the chance of the time becoming unsynchronized from an accidentally or intentionally misconfigured time source. These advantages are realized inside server in special clustering algorithm and the clock combination algorithm. Server NTS-3000/4000/5000 not only tries to synchronize to “true time”, it also computes an error range on all source inputs. The maximum error in either direction is called the dispersion representing offset and maximum possible time error. NTS-3000/4000/5000 server determines the best time sources based on several factors, including offset, the delay (latency), and statistical error factors (represents errors related to clock reading times and frequency tolerance etc).

Multisource can improve target output UTC accuracy by reducing final dispersion (thin grey interval)

UTC-multisource also helps reduce risk of time manipulations. Input clocks that have error bars (dispersion) that overlap this interval are in the majority. Input clocks that are in this majority are called “Truechimers” and clocks that are outside this majority are called “Falsetickers.” In most cases, all the clocks in a configuration will be Truechimers. If a clock at server’s input appears to be a Falseticker, then it is important to investigate to see what the problem is. While in an ideal world, all Falsetickers would be the result of incorrectly set clocks, it is possible (but very unlikely) that a Falseticker may have a incorrectly set clock as the result of time manipulation (i.e. GPS spoofing). These kind of tricky things are similar acting to “time machine”. Spoofing GPS is one of most popular, but unfortunately not the only one. Multisource offers unique possibilities to detect and eliminate Falsetickers.

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20. GNSS!Receiv er!&!Antenna!

Preparing for Antenna Mounting

NTS-3000/4000/5000 is equipped with active GNSS Antenna and receiver supporting:

• GPS

• GLONASS

• GALILEO

• BEIDOU

GNSS receiver is set for receiving multiple satellite systems simultaneously. Following configurations are available for each receiver:

• GPS+GLONASS (default)

• GPS+BEIDOU

• GPS+GALIILEO

• GLONASS+BEIDOU

• GPS+GLONASS+GALILEO

• GPS only

The GNSS configuration is factory pre-set and therefore must be defined before ordering. NTS3000/4000/5000 Servers can support max. 2 independent GNSS antenna/receivers getting simultaneously time from all 4-satellite systems:

• GPS+GLONASS+GALILEO+BEIDOU

Depends on above configuration receiver use between 32 (min) and 170 (max. option) independent channels. Each GNSS satellite system can supply independent data to calculate UTC output time.

Each of NTS-3000/4000/5000 servers is equipped with 2 independent antenna inputs (Channels: A/B). Each can operate as INPUT or OUTPUT:

Ch“A” Ch“B”

ANTENNA

Antenna INPUT (Ch “A”, CH “B”) can support simultaneously GPS/GLONASS/GALILEO/BEIDOU. Antenna OUTPUT mode can generate GPS NMEA+1PPS emulation to another server. There are 2

LED (red, green) on the back panel of NTS-3000/4000/5000 to indicate GPS, OCXO 1PPS synchronization. The following unit status is reported on LED's:

GREEN LED

STATUS

OFF

NTP daemon not started

NTP daemon started

BLINKS (NTS-3000 and -4000)

Synchronized to OCXO

BLINKS (NTS-5000)

Synchronized to 1PPS from external BNC connector, Rubidium or OCXO

RED LED

STATUS

OFF

No GNSS signal

Synchronized to GPS (NMEA)

BLINKS

Synchronized to GPS (1PPS)

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The hardware of the GNSS antenna contains in one box. In a box are placed GPS receiver, frequency converter and basic over-voltage protection. Box is water resistant (IP67) therefore it should stay over water level during rain.

Antenna w/ GNSS Receiver & Handler

Old header 2004-2014

New 2015 header w/ antenna

The old (2004-2014) GNSS active header supports only RS485 and GPS+GLONASS. The new 2015 GNSS header is 100% compatible to old header 2004-2014 (it supports RS485), but it also includes several optional extensions. It can be equipped with Ethernet (PTPv2/IEEE1588) and it supports all

available GNSS systems including: GPS, GLONASS, GALIELO, BEIDOU.

Available NTS-3000/4000/5000 antenna system configurations:

1. Single RS485 antenna/receiver connected to ANT1 (included with std. product set)

2. Dual redundant RS485 antenna/receiver connected to ANT1 and ANT2

3. Tipple (2xRS485; 1x PTPv2) antenna/receiver connected to: ANT1, ANT2, PTP#1 or PTP#2

4. Quarto (2xRS485; 2x PTPv2) antenna/receiver connected to: ANT1, ANT2, PTP#1, PTP#2

All antenna type of communication (RS585, Ethernet/PTPv2) are requiring UTP/STP min. CAT 5 cable. Maximum possible distance connections are:

• 0.6 km for RS485 via UTP min. cat. 5

• 1,2 km for RS486 via STP min. cat. 5

• 0.2 km for PTPv2 (no switch allowed) min. cat. 5

Ch“1” Ch“2” Ch“3” `Ch”4”

ANTENNA ANTENNA

RS485 4x antenna configuration PTPv2/IEE1588

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The GNSS satellite receiver has been designed to provide extremely precise time. High precision time is available 24 hours a day around the whole world from GNSS including: GPS, GLONASS, BEIDOU, GALILEO. The GNSS is a satellite-based radio-positioning, navigation, and time-transfer system. The source of time is based on Cesium (Cs) or Rubidium (Rb) atomic clocks. Time is represented as UTC.

The GPS, GLONASS and GALIELO satellites are not stationary. They circle round the globe in a period of approx. about 12 hours. The BEIDOU/COMPASS is geostationary.

At the time single GPS satellites can only be received if there is no building in the line of sight from the antenna to the satellite, the multi-SAT GNSS offers much better signal receiving sensitivity and time accuracy. The antenna unit should be mounted always at location of building from which as much of the sky as possible can be seen.

Panorama scheme of rooftops in the city (“OK” – recommended places to mount GNSS, “FINE” – places should be considered

for mounting, “NOT GOOD” – places you should avoid to mount your GNSS receiver)

The metal handler should be mounted always on top of building. Please select location of GNSS antenna on way it work will be not disturbed by any other radio-transmitter or antennas. We advice to keep min. distance of 5m from other electronic devices as GSM (2G/3G/4G) transceivers, radars, telecoms equipment, air conditions etc. Your GNSS multi-SAT antenna/receiver should be mounted solid to avoid strong winds and other bad weather conditions. Water, salt and snow conditions are acceptable under condition the box remind over water level (IP67).

GNSS

Country of origin

SAT in View

Purpose

GPS

USA

Military & Civil

GLONASS

RUSSIA

Military & Civil

BEIDOU/COMPASS

CHINA

14 (since Dec 2012)

Military & Civil

GALILEO

European Community

4 (since 2012)

Civil/Commercial (only)

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For surge and over voltage protection please refer to NTS-protec part of manual. This product is not included with std. set and needs to be purchased separately. NTS-protect includes special lightning protectors preventing NTS servers from direct and indirect effects of atmospheric discharges and related over voltage defects. The construction of NTSprotect is based upon the rule of voltage compensation in accordance with PN IEC61024-1 standard regulations. It stimulates upholding safe levels of over voltage that will not damage the

insulation in all protected electrical circuits of the NTS family servers.

For connecting antenna (GPS or DPS + DCF77) box we recommend usage of UTP or STP CAT5 (or above) cables with standard RJ-45 connector termination (both sides) with standard T568B conductors assignment. Cable should be leaded into antenna box through cable gland. Please use standard Ethernet cramping tooling (not included to NTS set) to mount antenna cable connection. See table below for RJ45/UTP-STP cat. 5 wiring and related signal specification.

RS485 configuration

Old RS485 antenna w/ RJ45

New RS485 antenna

Tools to mount antenna:

1) RJ45 connectors pcs.2

2) UTC or STP cat. 5 cable (RS485 version):

• 0.6 km (max) UTP

• 1.2 km (max) STP

3) Ethernet RJ45 Crimping machine

PIN RJ45

GPS Signal

UTP Cat 5 cable

PPS+

White/Orange

PPS-

Orange

TR+

White/Green

DCF-

Blue

DCF+

White/Blue

TR-

Green

+VCC

White/Brown

Brown

GND

Not used

RJ45 (UTP/STP cat. 5) cable and signal specification

Note! For PTPv2IEEE1588 Ethernet version of GNSS receiver/antenna the rules and limitations are limited by std. Ethernet communication and connections. Not switch/router is allowed when connecting

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PTPv2 antenna receiver (master clock) to timeserver acting slave clock. You can connect max 2 PTPv2 antennas to single timeserver. PTPv2 antennas are operating independent on rs485 receivers.

The GNSS signal performance is different depends on geographical location and time of day. The GPS, GLONASS and GALIELO satellites are not stationary. They circle round the globe in a period of approx. about 12 hours. The BEIDOU is geostationary. GALILEO can be used experimental.

GPS/GLONASS/BEIDOU satellites in view

Properly mounted GNSS antenna gives timeserver access to maximum satellites available. Large volume of available satellites improves performance of time synchronization. It has impact to time server accuracy and stability. It makes solution better resistant to radio interferences (e.g. mobile telecom network) and sat signal reflections (sky riper buildings etc.). Presented below sat signal strength is an example measurement result. Signal strength and volume of satellites change during day and therefore it is so important to take care for proper antenna installation.

Asia

Europe

USA

Asia

Europe

USA

Additional information on new GNSS sat systems BEIDOU & GALILEO (experimental)

BDS (Beidou/Compass - China) will be a global satellite navigation system consisting of 35

satellites in 2020, and is still under construction. It operates now with 10 satellites in view (as of

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December 2012, 16 satellites for BeiDou-2 have been launched, 14 of them are in service). Satellites are partially geostationary. The BDS could provide positioning data between longitude 55°E to 180°E and from latitude 55°S to 55°N. NTS-3000/4000/5000 supports Beidou signals on E2 (Carrier FRQ 1561,098 MHz). This carrier is generally similar to the civilian codes of GPS (L1-CA and L2C), but BDS signals have somewhat greater power. Other frequencies in four bands: E1, E2, E5B, and E6 overlaps with GALILEO sat signals and will be supported when GALILEO will be lunched.

GAL (GALILEO – EU) is a global navigation satellite system built by (EU) and European Space Agency (ESA). On 21 October 2011 the first two of four operational satellites were launched to validate the system. The next two followed on 12 October 2012, making it possible to test at timeservers NTS3000/4000/5000 since March 2013. The GAL firmware version is experimental. GALILEO satellites reminds in view periodically (max. 4) a few hours per day only. Full completion of the 30satellite Galileo system (27 operational and three active spares) is expected by 2020. The GALILEO system is intended primarily for civilian use, unlike the more military-oriented systems of the United States (GPS), Russia (GLONASS), and China (Beidou-1/2, COMPASS). The US (GPS) reserves the right to limit the signal strength or precision of GPS, or to shut down public GPS access completely, so that only the armed forces of the US and its allies would be able to use it in time of conflict. GALILEO use the same frequency and coding as GPS civil. It can be used experimentally only.

2015 BEIDOU sat in view Europe and Asia

Antenna Mounting

The antenna supplied is of the active type, and is suitable for almost all applications. It is not supplied with a pre-attached, cable, Before commencing installation, check that all the items detailed in the contents list have been supplied and ready. The antenna is supplied with 0.5 handler with mounting clamps for attachment to a mounting pole.

When mounting the antenna, ensure the antenna has a clear view of the horizon and is at least 2 meters away from transmission sources which may interfere with reception. Avoid the direct path of any microwave links. Using any GNSS sat tracing FREE software on your mobile phone check that signals are available at ratio is at least 33.dB and that at least 4 satellites are in view with this minimum S/N signal. If you do not get these results check another antenna position Caution! Do not allow the pole or other surfaces to extend higher than the underside of the antenna. Such a condition would impair signal reception. The most important consideration in selecting a position for the antenna is the presence of objects which obscure the sky or horizon. Where possible,

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there should be no obstruction to a full view of the sky. Overhead wires and other very narrow obstructions may be considered as invisible to the signals, provided that they are a few meters.

Be especially wary about mounting the antenna directly onto the fascia of a flat roof. To overcome this situation, elevate the pole about 1 meter above the flat surface. A satellite prediction program may usefully be employed to check a potential installation, and also to identify directions in which obstructions may be a particular source of problems. The antenna is connected to the GPS Receiver by a coaxial cable fitted with TNC connectors at each end. Where possible, avoid exposing the cable and connectors to weather and other environmental conditions.

To install the antenna:

1. Insert the antenna cable through the bracket and the tightening pipe.

2. Fasten the tightening pipe to antenna.

3. Insert bolts through the mounting pole and connect to the bracket.

4. Insert flat Washers & Spring Washers & Nuts and close.

Multi-SAT RCV/Antenna (2000-2014) New 2014 Receiver

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21. NTS-protect!(Extra!Surge!Protection)!!

As the antenna is roof mounted (to have a clear view of the sky) it is likely to be exposed to lightning strikes. Protection against this is afforded by ensuring adequate grounding of the mountings as described below.

CAUTION! There is no way to provide 100% protection for electronic equipment from direct strike damage. It is possible however, to reduce the likelihood of damage from near strike induced fields by ensuring the installation obeys some fundamental rules.

Lightning arrestors are not 100% efficient, a residual attenuated electrical pulse being transmitted down the antenna cable, may still contain sufficient energy to damage equipment within the building. Therefore, a second lightning arrestor is required at the equipment end of the cable, preferably where the antenna cable enters the building.

ENSURING THE ANTENNA MOUNTING BRACKET AND NTS-x0000 ARE PROPERLY GROUNDED. This must be achieved by employing a certified, low impedance connection (a broad, flat lightning conductor strap of sufficient thickness to provide adequate mechanical durability) able to carry the thousands of amperes which may flow. Attaching the antenna mounting clamp onto a pole which is correctly grounded is the recommended method. Optionally another lightning arrestor should be mounted where the antenna cable enters the building and properly grounded to earth termination.

NTS-3000/4000/5000 includes std. industrial overvoltage protectors on all I/O lines including all GNSS antenna inputs. However GNSS receiver with active antenna located on the building roof can be connected to a remote NTS-3000/4000/5000 server via extra high performance lightning protector system from Phoenix Contact (The NTS-protect unit). This system is a unit of surge/overvoltage and lightning protection preventing the time server from direct and indirect effects of atmospheric discharges. The NTS-protect system has been designed so to be in compliance with the regulation (Journal of Laws, No. 75 of June 15, 2002 items 180 and 183) providing that wiring systems should secure against switching overvoltage and lightning surge, and that voltage limiters shall apply thereto. The construction of the unit is based upon the rule of voltage compensation in accordance with PN – IEC 61024-1 standard. It stipulates upholding safe levels of overvoltage that will not damage the insulation in all protected electrical circuits of the NTS-3000/4000/5000 server.

NTS-protect minimum configuration supports lighting protectors for: 1) GNSS antenna; 2) LAN, 3) 110230V AC single power input.

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NTS-protect maximum configuration supports all I/O including: 1) 2x GNSS antenna (RS485);

2) 2-6x LAN (both: NTP and PTPv2), 3) 110-230V AC dual redundant power input.

General operational description

All in/out lines of the NTS-3000/4000/5000 server have been conducted through overvoltage limiters mounted altogether on the steel-made DIN35/7,5mm bus, a standard solution applied to industrial automatics for rack’19 switchboxes. The height of the solution is 2U and it is mounted inside the rack’19 switch box, on the back of the NTS-x000 server. Overvoltage limiters are arranged as parallel systems including non-linear components such as gas spark gaps, semiconductor diodes and voltagedependent resistors. They provide a quick change of resistance leading the current of overvoltage origin down into the protection circuit (yellow and green wire) of the rack’19 switchbox. All electrical leads of limiters are in the form of screw terminals.

Phoenix Contact NTS-3000/4000/5000

Limiter type Description (general purpose of using)

PT 5-HF 12V GNSS (GPS/GLONASS/GALILEO/BEIDOU) protectors PT 2-PE/S 24V Antenna/Receiver power protector D-LAN-CAT.5E-U LAN/Ethernet VAL-MS 110-230V AC power protector

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Description of antenna track protection

The NTS server communicates with the GNSS antenna module via lowsignal circuits of the voltage levels not exceeding 12V DC. The transmission is carried out through a special multi-core cable of a core diameter equaling 0,5 mm. The cable has two separate 1,00 mm lines providing power supply to the antenna. The aforesaid lines are protected with two-component limiter (3 pcs.) mounted onto a DIN35/7,5mm bus with a down lead into the protection circuit. Cramps holding odd numbers are equipped with a cable leading into the GNSS (GPS/GLO/BDS/GAL) antenna module (roof direction) whilst cramps holding even numbers go with the NTS-3000/4000/5000 server. Please refer to GNSS Receiver & Antenna chapter for details on connecting antenna via UTP/STP cable.

Server antennas (RS485)

Ant 1 (Ant 2)

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Description of Ethernet link protection (2 x LAN Cat. 5).

Protection of the Ethernet lines is provided due to additional reduction of the risk resulting from damages that may occur via LAN/WAN network. The solution has been designed in compliance with IEC 61643-21 standard. System holds D-class certificate in accordance with DIN EN 50173-1:2002 standard for LAN network solutions. The limiter is connected to the NTS-3000 server and LAN/WAN network with standard Cat. 5 wires. The length of wires along the “NTS server – lightning protector” track should be of the least possible value. The lightning protector is mounted onto a DIN35/7,5mm bus whilst its protection wire is linked to the protection circuit (yellow and green wire) through a special cramp on the rack.

The system holds D-class certificate in accordance with DIN EN 50173-1:2002 standard for LAN network solutions. The limiter is connected to the NTS-3000 server and LAN/WAN network with standard Cat. 5 wires. The length of wires along the “NTS server – lightning protector” track should be of the least possible value. The lightning protector is mounted onto a DIN35/7,5mm bus whilst its protection wire is linked to the protection circuit (yellow and green wire) through a special cramp on the rack.

Description of power supply system protection (230V AC)

Due to wide scope of applications and high efficiency as well, the system has been assumed to be provided with the protection made for the entire rack’19 switchbox. Then the issue to discuss is barely the way the power is distributed inside the rack’19 switchbox (it refers to the number of internal outlets mounted onto the bus) and not the way of supplying the power to the entire rack’19 switchbox along its appropriate earthing system. So the protection of the 230V AC power supply system has been handled through C/II-class limiters in accordance with IEC 61643-1 and E DIN VDE 0675 standards. These are limiters maintaining the protection level parallel to D-class (reaching 1m5kV for 20kA at 8/20uS) and allowing for the down lead of the current up to 3kA (10/350uS), typical for supplementary safety measures that include protection of the 230V AC power supply system. Such solutions are in regular use in the industry, for rack’19 switchboxes with the industrial automatics. NTS-protect solution has 2 limiters of this kind (one in each wire), working in parallel in the power supply system. Limiters are installed onto the DIN35/7,5mm bus. It is recommended to provide the discussed system with supply for devices operating in the same

110-230V AC protector

(single power supply system)

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rack’19 switchbox

Final information and general supplementary recommendation (NTS-protect)

1. The DIN35/7,5mm bus must be joined to the protection circuit of the electrical terminals

2. All wires (including those of other devices) inside the rack’19 switchbox, that may cause overvoltage should be grouped so that they stay away from each other. Cores of the wires should go together and keep a relevant distance.

3. All wires connected to the protection systems should be of the least possible length.

Remember that the NTS-3000/4000/5000 unit only minimizes the probability of damages resulting from overvoltage and arising directly or indirectly as a consequence of atmospheric discharges, however, it provides no absolute warranty against overvoltage.

Rack’19 back panel with NTS-protect

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22. FO-converter!(Fiber!Optic!Con verter)!!

Electric signal side

Fibber Optic side

The FO converter can be used to connected GNSS MulitSAT receiver to NTS3000/4000/5000 Timeserver. The max. connection distance is 1.5 km (1 mile). Single antenna (A/B) requires 2 converters connected on each side of :

• GNSS Mulit-SAT Receiver/Antenna (via RJ45)

• NTS-3000/4000/500 Time Server (via RF45)

! !

Connection scheme for single GNSS-Timeserver communication

62!

Connection scheme for double redundant GNSS-Timeserver communication

ST single-mode fiber optic (conv2conv)

Quick installation:

NTS-x000 (RJ45) 24VDC Ant/Rcv (RJ45)

1. Prepare 2pcs of FO-conv for each MultiSAT antenna/receiver. For Dual antenna system (A/B) use 4pcs of FO-conv (2pcs/antenna).

2. Connect FO-conv using singlemode (ST ended) fiber optic wire (top side of picture)

3. Connect FO-conv #1 to NTSx000 unit using UTP cat 5. Plug the cable into RJ45 connector of FO-conv labelled “Time Server”. Another side of cable plug into NTS-x000 ANT#1 (or ANT#2).

4. Connect FO-conv #2 to GNSS Ant/Rcv using STP cat 5. Plug the cable into RJ45 connector of FOconv labelled “MultiSAT Antenna”. Another side of cable plug into NTSx000 ANT#1 (or ANT#2).

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Powering fiber optic converter (FO-conv)

FO-conv requires 24VDC. Unit #1 can be powered directly from NTS timeserver antenna connector (RJ45) located at back panel (label ANT1 or ANT2). Unit #2 is connected to GNSS MultiSAT Ant/Rcv and it is requiring external power supply.

GNSS receiver connected to electric circuit #2 does not interfere IT electric circuit #1 when surge

It is strongly recommended to use separated from main IT hardware 110/230V AC electric circuit. Since fiber optic is not caring electricity, using separate 110/230V AC powering (or solar panels) for GNSS MultiSAT Ant/Rcv makes solution 100% resistance for surge and overvoltage.

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23. Robust!Sync!-!Application!Notes!

Following GNSS antenna installations are bed practice and do not appoint robust synchronization standards:

Examples of bed practice GPS antenna installations

When considering robust installation please consider risk of GPS jamming/spoofing too. There are various of Internet shops offering professional dimmers in reasonable inexpensive price. Some of technical reports provides information on cyber-attacks to Stock Exchange GNSS receiver systems.

Jammers are inexpensive and public available

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! !

66!

24. Powering!Up!

If both the antenna and the power supply have been connected the system is ready to operate. You can turn on a power switch located on the back panel of NTS server.

Typically, time duration of NTS server power-up is enough for the GNSS MultiSAT antenna/receiver box to start to operate with the required accuracy. If the GNSS MultiSAT antenna/receiver finds valid almanac and ephemeris data in its battery burred memory (and the receiver position has not changed significantly since its last operation) the receiver can find out which satellites are in its view at that now.

At least 4 satellites must be found to synchronize and generate output 1PPS pulses. Typical systems work in configuration they have constant view of 12-32 GNSS satellites.

If the receiver position has changed by some kilometres (since the last operation), the satellites real elevation and Doppler might not match the values expected by the receiver thus forcing the receiver to start scanning for satellites. When the receiver has found four satellites in its view it can update its new position and switch to Normal Operation. If the almanac has been lost because of battery disconnection the receiver has to scan for a satellite and read in the current almanacs. When antenna has clear view of the sky it takes up to 30 minutes until the new almanacs is completed and the system starts to operate. For this time NTS server will operate from its internal quartz time clocks (NTS-3000) or OCXO (NTS-4000), or Rubidium oscillator (NTS-5000).

After starting up the system the network function is initiated and the program for communication between GNSS and NTP (Network Time Protocol) becomes to be active. The following screen appears on LCD display while starting.

From the left side there are: date and time, error status, UTC time, number of satellites reached per total amount of visible satellites.

Important Note!

The NTP starts max. 5-10 minutes after powering ON it does not matter what status of time sources actually are (if they are connected, GPS is synchronized etc.). During this approx. 5 minutes long start time NTP searches for best available source and builds statistic information in order to be able to detect corrupted sources (false tickers in NTP notification). After approx. 5-10 minutes period NTP selects best source as currently used and other sources (also correct but less accurate) as backup sources.

It is possible to setup much shorter start-up time of NTP (about 1 minute) by selecting a special “Fast” option in “Misc” menu of SETUP. This can be helpful for environments with a high risk of unexpected power down. Using this option results in less accurate (approx. 1s error of time information provided by NTP service during first 3-4 minutes of operation).

The OK status is displayed if system tracks satellites and synchronisation is pending. For single antenna system only one receiver status is displayed. For double GNSS antenna/receiver configuration each receiver shows it’s own status - one after another one.

03-05-2014 ERRsync

12:01:00 sat A= 2/32!

03-05-2014 OK

12:01:00 sat A= 18/32!

03-05-2014 OK

12:01:00 sat B= 16/32!

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25. LCD!Messages!

If no antennas are currently connected to NTS devices following error screen will be shown:

Error: all antennas disconnected

The NTS servers require minimum 5 satellites to be reached continuously in order to get time from GNSS (GPS) properly. This figure is not constant and it is changing in non-regular way. If satellite communication is lost the following message appears:

Error: missing GNSS statellites

Error: bad GNSS geometry (min 5 sat)

This requires finding better GNSS antenna location otherwise NTS servers cannot obtain time information from GNSS antenna. The unit will still work properly but will provide time according to RTC which time need to be setup manually through console and its accuracy is poor.

Error: GNSS is not in sync

Error: Device out of order

17-02-2015 ERRsats 18:02:21 ANT ERROR

17-02-2014 ERRsats 8:02:21 sat A=1/12

17-02-2014 ERRsync 8:02:21 sat A=5/12

Error call service +48 (22) 7517680

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26. Keyboard!Setup!

After first power up, at least basic configuration should be performed in order to setup proper interfaces IP configuration. This can be done using front panel keyboard.

Front panel Keyboard

To enter setup mode press and hold “OK” button. Now you can configure LAN1 interface. Following screens will appear on LCD:

To navigate through digits, use “←” and “→” keys. To increase values, use “↑” key, to decrease use “↓” key. One can instantly clear currently edited parameter to zeros by pressing “C” key. Pressing “OK” button switches to next parameter. After configuring LAN1 interface, LAN2 interface screens are shown. After configuring all parameters following screen is shown:

Configuration confirmation screen

In order to save configuration press “OK” button. NTS server will reboot and operate with new setting. If you want to keep old configuration simply press “C” button and no changes will be made. In order to exit from configuration mode just press “OK” button as many times as needed to obtain confirmation screen and then press “C” button. This operation must be done with caution in order to avoid saving bad settings.

This method allows only base LAN1 & LAN2 interfaces configuration. In order to change other NTS server settings console (incl. LAN3-LAN6 options) software configuration option is available via HTTP, HTTPS, SSH or TELNET. For quick SETUP details please ref. to Chapter 1 of this manual.

LAN1 IP address:

192.168.000.210

LAN1 netmask:

255.255.255.000

LAN1 gateway:

192.168.000.001

Are you sure? [OK]-Yes [Cancel]-

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27. Restoring!Factory!Defaults!

NTS-3000/4000/5000!(Factory!Default!Setting)!

Standard LAN defaults:

LAN1: 10.0.0.210 MASK: 255.255.0.0 GATEWAY: 10.0.0.1 LAN2: 192.168.0.210 MASK: 255.255.255.0 GATEWAY: 192.168.0.1

Optional LAN component settings:

LAN3: 192.168.3.210 MASK: 255.255.255.0 GATEWAY: <no value> LAN4: 192.168.4.210 MASK: 255.255.255.0 GATEWAY: <no value> LAN5: 192.168.5.210 MASK: 255.255.255.0 GATEWAY: <no value> LAN6: 192.168.6.210 MASK: 255.255.255.0 GATEWAY: <no value>

Factory default user and password:

Username: admin Password: 12345

SETUP!services!defaults:!

HTTP!! !! ON! HTTPS!!!! ON! SSH! ! ON! TELNET!! OFF! !

Std.!product!supports:!!!!!!!! GNSS!(GPS/GLONASS)! Custom!product!supports:!! GNSS!(GPS/GLONASS/GALILEO/BEIDOU)!

Interfaces: Defaults Available NTS-x000 modes rs485 Ant1 (Antenna “A”) INPUT INPUT (all) RJ45

OUTPUT (NTS-4000 & NTS-5000 only) RJ45 DISABLE (NTS-4000 & NTS-5000 only)

Ant2 (Antenna “B”) INPUT INPUT (all) RJ45

OUTPUT (NTS-4000 & NTS-5000 only) RJ45 DISABLE (NTS-4000 & NTS-5000 only)

Restoring!Factory!Defaults!

Press!&!hold!(at!the!same!time)!“OK”!and!“C”!buttons,!until!following!below!message!will!be!displayed!on!LCD.!

Press!“OK”!one!more!time!to!RESET!product!and!RESTORE!factory!defaults,!or!press!“C”!to!abort!the!operation.!

Following!below!message!will!be!displaced!on!LCD!and!needs!to!be!confirmed![OK]!“Yes”!

You need to confirm before restoring to factory defaults

Are you sure? [OK]-Yes [Cancel]-No

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28. UTC!Multisource!Inputs!of!NTS!

NTS-x000 supports simultaneously several UTC sources. The inputs UTC groups are:

• GNSS satellite systems (GPS, GLONASS, GALIELO, BEIDOU via: RS485 or LAN)

• Remote TIME SERVERS (NTP, PTP/IEEE1588:2008, IBM SYSPLEX, IRIG-B)

• Local external atomic clocks (IRIG-B, 1PPS, 10MHz, RS-232)

Simultaneously supported ref. UTC inputs

The UTC sources are:

1. GPS

2. GLONASS

3. GALIELO* (option)

4. BEIDOU* (option – not available in Europe)

5. NTP – Network Time Protocol (max. 2)

6. PTP/IEEE1588:2008 – Precision Time Protocol (max. 4)

7. IBM SYSPLEX (SYS)

8. IRIG-B in

9. 1PPS in (EXT)

10. 10MHz in

11. RS-232 in

Multisource concept. NTS-5000 Time Server simultaneously receives time from all available UTC time sources

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29. Maintaining!Holdover!mode!(NTS-5000)!

This chapter is limited to NTS-5000 only. Once server is installed and powered up, the NTS-5000 continuously receives UTC from available sources simultaneously. This is done by Grand Master Clock (GMC) submodule – the central hart of NTS-5000 server.

After starting NTS-5000 it synchronizes its internal oscillators (Rubidium and OCXO)

The GMC is analysing all input UTC references simultaneously watching for best performance one, and switching into it (1PPS+ToD). At the same time GMC is providing UTC ref. to local oscillators OSC (Rubidium, OCXO).

This process takes 15-30 minutes, but preliminary output UTC is available via LAN1/ LAN2 supporting NTP (Network Time Protocol) with accuracy of milliseconds. The NTP is available already 1 minute after switching power ON of NTS-5000 and it takes another 4 hours to improve accuracy of NTP (Lan1 and Lan2) to level of microseconds.

Once OSC (Rubidium, OCXO) oscillators are synchronized to UTC ref. input (e.g. GNSS) the NTS5000 GMC is ready to serve PTP interfaces and also it is able to support HOLDOVER mode.

The holdover mode is autonomous GNSS less operation, where ref. UTC is drown locally from oscillators (Rubidium, OCXO). Independently, outputs as PTP 1-4 or NTP includes own local-holdover mode that extends autonomous interface operation in case if internal synchronization signals remind temporary unstable (e.g. because of EMC impacts from other devices etc). This technology warranties high quality and performance of NTS-5000 that is able to operate GNSS less for many weeks.

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Time arrow Server Activity Time on outputs Accuracy

ZERO Power up (switchin-ON) None N/A

0-1 min Booting None N/A

1-15 min GMC is receiving GNSS LAN1-LAN2 millisecond LAN3-LAN6 N/A GMS is syncing OCXO

15-30 min GMC is receiving GNSS LAN1-LAN2 millisecond LAN3-LAN6 microsecond OCXO synced by GMC 1PPS+ToD GMS is syncing Rubidium

30-60 min GMC is receiving GNSS LAN1-LAN2 sub-millisecond LAN3-LAN6 sub-microsecond OCXO synced 1PPS+ToD GMS synced 1PPS+ToD

30-60 min GMC is receiving GNSS LAN1-LAN2 sub-millisecond LAN3-LAN6 sub-microsecond OCXO synced 1PPS+ToD GMS synced 1PPS+ToD Ready for holdover

60-240 min GMC is receiving GNSS LAN1-LAN2 microseconds LAN3-LAN6 nanoseconds OCXO synced 1PPS+ToD GMS synced 1PPS+ToD Ready for holdover

Note!

Best performance NTS-5000 server is reaching after 4 hours since powering ON. Therefore NTS-5000 is supplied with dual redundant power supply and it should be installed with 2 redundant GNSS receivers.

The 1-4 PTP modules as well as NTP module can be independently be equipped with local TCXO oscillators that provides additional holdover operation for this specific module. It is useful in case if NTS-5000 operates in noisy environments where there is a risk of EMC interferences. For more information, please ref. to PTP/IEEE1588:2008 section later in this documentation.

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30. S oftware!setup!for!std.!LAN1-LAN2!

This chapter will let you configure std. LAN1 and LAN2 interfaces (100/10 Mbps) of NTS-x000 family products. All below presented operations of configuration are similar NTS-3000, NTS-4000, NTS-5000 but this chapter will describe details based on example of server NTS-5000.

The factory default (user and password) is:

Username: admin Password: 12345

To start configuration, please configure all LAN interfaces by simply placing:

IP MASK DEFAULT GETEWAY

In addition, you can specify what mode you want to work on specific LAN interface. You can enable extra broadcast and multicast modes running in the background of standard client/server mode, but we suggest to finish basic configuration first before you go to more advanced options. Therefore, please leave those options for the moment now by simply filling fields 0.

Now it’s time to decide what other remote services you like to keep active for future accessing. You access each LAN separately:

• Enable/Disable access via Telnet

• Enable/Disable access via SSH

• Enable/Disable access via HTTP

• Enable/Disable access via HTTPS

• Enable/Disable access via SNMP (MIB2)

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Now you should repeat above steps for LAN2. It is strongly recommended to use only 1 of 2 (LAN1 or LAN2) GATEWAYS. So, if you have chosen GATEWAY for LAN1, please do not use GATEWAY for LAN2, and vice versa. It is because using 2 GATEWAYS simultaneously might cause risk of redirecting IP return packages to wrong GATEWAY output. This is well known problem for Unix and FreeBSD. To prevent such unexpected behave we recommend setting static routing.

A static routing is useful when considering stub network, or pocket network. This is a somewhat casual term describing a computer network, or part of an internetwork with no knowledge of other networks, that will typically send much or all of its non-local traffic out via a single path, with the

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network aware only of a default route to non-local destinations. As a practical analogy, think of an island which is connected to the rest of the world through a bridge and no other path is available either through air or sea. Continuing this analogy, the island might have more than one physical bridge to the mainland, but the set of bridges still represents only one logical path.

NTS-x000 can use VLAN’s when linked to CISCO (for information contact ELPROMA).

You can also specify SYSLOG server for future tracing functionality. You can configure facility and verbosity of NTS server messages, to ease log segregation on your syslog server. Please read syslog documentation for details about logs gathering.

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If your network supports SNMP, you can configure special MIB2 traps to implement exceptional facts you can be interesting in. It is very easy to set traps on such way that you will be informed by mail or mobile phone (SMS) on any unexpected situation may occur inside NTS server like e.g. losing GNSS antenna signal etc. Also you can trace all IP statistics using your favourite SNMP client (ie. Mrtg)

Another step is to define up to 10x NTP backup servers for single NTS server unit. In this mode NTS server reminds Stratum 1 if GPS antenna works fine or any other time source (PPS_IN, Rubidium/NTS-5000only, OCXO). But in case of missing accurate time source NTS server checks backup servers list. If NTP accepts any of them the NTS server reduce its stratum to N-1 (where N is a Stratum of approved server taken out of backup list). We advise to specify only Stratum 1 servers on NTS server backup list. This does not let reduce NTS server Stratum below 2. The backup NTP servers should be configured for authorized NTP transmission. For this reason, there is another field key pointing position in encryption list with MD5 keys. But in this step we still advice to continuous Setup without encrypted associations. Safety and protection will be discussed shortly in this manual.

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Setting DATE/TIME is a tool to pre-set LOCAL clocks time. It always use to be UTC however some customers use this option to maintaining other than UTC timescales (GPS). This can be useful option to maintain local zone time too.

Time Zone service lets set LCD time to local time. It has information meaning only and timeserver works and supports universal UTC timescale.

AUTH includes set of settings related to security and authentication including MD5 and SSH/SSL keys.

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Upgrade. To perform firmware upgrade you should put USB memory stick with new firmware into port on front panel and then activate this option. GPS. With this function you can monitor GNSS receiver messages on line, just as they came. You can check receiver location and GPS status bits. ANT A/B DIR. This functions give you ability to send time signal in NMEA/PPS format to another NTS series unit. Just configure one antenna socket as an output (O) and connect it with 1 to 1 twisted pair cable with RJ-45 TIA-568B connectors to antenna input (I) of second NTS.

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Once setup is done you have to exit with save option. Do not turn off power when NTS is saving settings (appropriate message appear on LCD). The NTS–5000 supports SETUP available via SSH and TELNET service or serial console port located on front panel (DTE configuration, 9600 baud, 8 data bits, no parity, 1 stop bit).

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31. PTPv2!Setup!of!PTP1-LAN4!(LAN3-LAN6)!!

As NTS-5000 low-level hardware (HW) implementation of Precision Time Protocol (PTP) aspires to deliver a full and faithful PTPv2 experience, the original documentation of PTP/IEEE1588:2008 is valid and does not need to be repeated. We strongly recommend original IEEE release documents, and

restrict this documentation to help some topics to get you started quickly with PTP.

This chapter includes information exclusively dedicated to NTS-5000 PTP hardware extensions. The NTS-5000 must be equipped with 1-4 optional hardware PTP interfaces located at back panel of server. NTS-5000 is delivered with built-in (mounted) and recalibrated PTP interfaces. All hardware PTP interfaces must be ordered and assembled at factory due to internal latency calibration necessary to achieve high nanosecond accuracy of PTP. If you have ordered less that required PTP interfaces, please contact Elproma technical support.

PTP #1 PTP #2 PTP #3 PTP #4

NTS-5000 Back Panel w/ high precision x4 interfaces: PTP1, PTP2, PTP3, PTP4

PTP #1 PTP #2 PTP #3

NTS-5000 Back Panel w/ high precision x3 interfaces: PTP1, PTP2, PTP3

PTP #1 PTP #2

NTS-5000 Back Panel w/ high precision x2 interfaces: PTP1, PTP2

PTP #1

NTS-5000 Back Panel w/ high precision single PTP1 interface

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Ultra-high precision nanosecond [ns] PTP/IEEE1588 extension card

PTP1-PTP4 hardware extension board (top view) PTP1-PTP4 panel view

PTP1-PTP4 hardware extension cards at NTS-5000 (front view)

PTP1-PTP4 hardware extension cards at NTS-5000 (top view)

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Back panel view (3 units)

The 1-4 hardware PTP cards must be factory pre-installed. The firmware software setup automatically recognised them and a new menu item PTP is displayed a last line before Exit item:

The std. UID and Password for setup are:

Username: admin Password: 12345

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Depends how many PTP cards are installed the menu will look like:

Please configure each PTP1 (PTP2, PTP3, PTP4) card separately depends on your requirement. Below, configuration presents typical PTP configuration for financials set to appoint ESMA MiFID II requirements.

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The meaning of each line/parameters are:

(1) Reference time

It is a Grand Master Clock UTC time, the central time of NTS-5000 Time Server. At GPW the UTC ref. time is simultaneously drawn from GNSS receivers (max. 2) and automatically stored to internal clocks powered by 2 redundant oscillators: Rubidium and OCXO. This time is centrally redistributed to all time related interfaces incl. PTP, NTP, IRIG-B, SYSPLEX, 1PPS-out, 10MHz-out etc. This time is internally distributed to 1-4x PTP-Masters cards using 1PPS/ToD hardware signals.

Grand Master Clock interfacing – general scheme (GPW configuration)

The Reference Time is maintained automatically with nanosecond accuracy and resolution, and it is displayed no real time at software setup level. It has general information purpose meaning due to NTS-5000 is a multi-clock instrument.

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Reference Time Input – list of all possible UTC sources of NTS-5000 served simultaneously.

Light grey colour indicates inactive ref. sources for GPW; Black Colour indicates active one at GPW

Reference Time Outputs – list of all possible UTC outputs of NTS-5000 (served simultaneously)

Light grey colour indicates inactive ref. sources for GPW; Black Colour indicates active one at GPW.

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(2) PTP UTC Time

This is UTC time at PTP BUS (hardware level) PTP modules inputs. It is the same time as GMC (Grand Master Clock) sent, but on another side of the bus – at arrive to PTP module hardware. This is common time delivered to each of 1-4 PTP modules. Since it is common time (shared by bus: 1PPS + ToD serial communication) it is represented by single field value.

PTP UTC Time – input UTC time at PTP hardware modules (1-4)

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(3) The PTP Time (PTP UTC Offset)

UTC time at PTP (Precision Time Protocol) is represented by formula:

UTC= TAI - #LEAP_SEOCONDS

Therefore, it must be disassembled from 1PPS+ToD information that arrives to PTP hardware first.

The PTP time field points the time in TAI (Atomic Time Scale), and the next line field PTP UTC Offset provides UTC to TAI offset information. Before December 31st of 2016 the LEAP_SECOND=36s, and on midnight of UTC the January the 1st 2017 New Year begins and new 37th LEAP SECOND will be added automatically. Above information is stored to Ethernet PTP-Master outputs at PHY stamping and with very high accuracy of hundreds of nanoseconds.

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(4) Time Transfer Bus: PPS input, TOD input, PPS source

Internal Timing Bus redistributes UTC time from

GMC to all 1-4 PTP autonomous op. modules

The Time Transfer Bus (TTB) supports following synchronization signals and dataflow:

• 1PPS (Pulse Per Second) high accuracy frequency reference. Built-in 1:4 signal splitter share this single GMC reference to all 1-4 PTP modules.

• ToD (Time of Day) UTC phase data information. It tightly corresponds to 1PPS above data. It is sent via serial communication to all 1-4 PTP modules.

• Extended info package of data includes additional information from GMC incl. LEAP_SECOND and ERROR BUDGET.

Unless several unexpected factors are in the account, in broad outline it can be assumed rightness that Reference Time is equal PTP Time. Those factors are:

a) Latency if I/O at GMC module output and PTP module input b) Latency of time transfer at TB (Internal Time Transfer Bus between GMC and PTP module) c) Time scale computing algorithms TAI-UTC d) Others minor factors

The NTS-5000 unit arrives factory pre-calibrated. However, because of aging of electronic elements

some differences can be observed in the future. This might require recalibration. A furthermore, NTS-5000 provides self-audit monitoring. It gives additional information about stability

of internal synchronization signals (1PPS, ToD) at the time they arrive from TTB to PTP.

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Those parameters are:

ToD input: <value> PPS input: <value>

Value:

• Stable - when TTB signals are examined by PTP module to be stable

• Unstable - when TTB signals are examined by PTP module to be unstable

The PTP modules switches then to local holdover (HO) mode TCXO/OCXO driven

• Unknown - when PTP cannot examine the quality of TTB input signals to be stable/unstable

There are several possible scenarios of action when other than Stable status is reach. This manual is not providing details on such algorithms. Nevertheless, the USER should assume NTS-5000 unit is trying to resolve the problem automatically at GMC level, by eg. changing output referential signals sent by TMC to TTB.

Before Rubidium/OCXO are synchronized, other values like PPSa (GNSS#1) or PPSb (GNSS#2) can be observed too. Once NTS-5000 unit has been switched ON and GMC synchronizes its Rubidium and OCXO oscillators the TOD/PPS input source mostly displays values as Rubidium and OCXO. This enables another level of synchronization process – the PTP 1-4 module synchronization preparing for PTPv2/IEEE1588:2008 generation each.

1-4 PTPv2/IEEE1588:2008 autonomous operating modules- each with own local TCXO oscillator and

PTPv2/IEEE1588:2008 output generation 1-4:

Each of 1-4 PTP modules is prepared for autonomous operation – PTPv2/IEEE1588:2008 standard generation to Ethernet (SFP or RJ45).

Before modules are operational ready they local clocks needs to be synchronized first. Each module includes at least TCSO oscillator for local holdover operation. Each module includes autonomous operating Master Clock (MCLK) too.

The synchronization process of 1-4 PTP modules can be traced via variables:

Clk sates: Syncing Clk sync : Yes

The PPS source can be:

• Rubidium (GMC level)

• OCXO (GMC level)

• PPSa (GNSS #1)

• PPSb (GNSS #2)

• EXT (1PPS-in EXT)

• SYS (SYSPLEX)

• IRIG (IRIG-B IN)

Note! After both internal oscillators (Rubidium and OCXO) are synchronized to GNSS, the NTS-5000 users mostly observe status of PPS source:

• PPS source: Rubidium

• PPS source: OCXO

Time Synchronization Bus GMC-PTP(1-4)

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clock (Master Clock – MCLK)

Above variables are described on next page.

(5) Master Clock PTP modules (Clk states, Clk sync)

Assuming the PPS/ToD input signals (sent via TTB) are stable, the PTP modules are beginning their local Master Cock (MCLK) synchronization. Each of max. clocks are synchronized separately to let PTP modules operate autonomous and independent on each other. Each 1-4 module includes own operating system with own IP stack (IPv4/IPv6) to support RJ45 or SFP (one in time only). The PTP modules separation is essential for security at financial business (HFT) and it is regulated by ESMA MiFID II regarding synchronization accuracy and UTC time resolution.

PTP1-PTP4 hardware MCLK (Master Clock PTP) modules in NTS-5000. Each with HW low-level time stamping

Clk states variable provides information of local MCLK (Master Clock) synchronization process of

PTP module.

Clk states: <status>

status:

Syncing – when MC is synchronizing to GMC

HOLDOVER! – when MC is operating from local TCXO FREE! ! – when MC is operating FREE RUN mode TCXO

!!!(MC reminds unsynchronized, e.g. after internal RESET) unknown! – shortly after reset of module, or if module is not responding Syntonizing!!!!!!!-!!when MC intervals are syntonizing to ref. interval definition !

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In addition, the Clk sync information is provided and it can be neither Yes – if MC is synchronized to GMC, or No – if not synchronized. Together, with Clk states it provides full information on PTP module operating autonomous. The synchronized and stable operationally unit mostly displays:

Clk states : Syncing

Clk sync : Yes

where, MC is synchronized to GMC (TTB signals are stable) but it is consciously synchronizing to keep best synchronization accuracy and MC performance. In case of getting PPS or ToD input Unstable, the Clk states transfers to HOLDOVER (assuming the Clk sync was previously Yes). Similar situation after module (or unit) reset might conclude with data outputs Clk states : FREE or earlier directly after reset Clk states : unknown (assuming the Clk sync is No). In addition, the

Mode value parameters can be traced for screen for maintenance tracing:

mode: <value>

value:

Master loop – MC is operating (communication is OK), PTP produces ETH output Close – communication PTP module INPUT is close (NO communication) Connecting – GMC is trying to lunch connection to PTP module INPUT Read config – GMC is reading PTP module configuration (communication OK) Configuration – PTP module configuration is pending Init – initializing PTP module Booting – PTP module is booting Cli wait – PTP module is waiting for command sent by GMC

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(6) PTP module self-audit (PPS in/out software monitoring)

Each of the PTP modules is operating autonomously. It includes own OS (Unix base), IPv4/IPv6 stack. PTP module is synchronized to GMC via TTB. The precision input synchronization is 1PPS-in. The PTP synchronization module also produce output 1PPS-out. The PTP time reminds in range between <1PPS-in..1PPS-out>. Signal offset difference (HW PPS Offset) can be measured by interval counter or oscilloscope. In standard operation this offset is counted in hundreds of nanoseconds [ns].

But, each PTP module also includes a self-audit software that can do the same but with much less accuracy because it basis on software macro-measurement. The variable name is PPS in/out. It provides information counted in microseconds. This information can be used for general information purpose only. As far as observed figures are below 100 microseconds the system assumes to operate

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normally. Observing figures larger than 100 microseconds might cause requirement for additional hardware measurement and calibration. The top screen presents PPS in/out=17 microseconds.

(7) NIC

Each PTP card provides NIC parameters including MAC and type of Ethernet connection (1GE, 100/10 Mbps).

(8) Network

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Each ETH interface can be configured for IP, MASK and GETEWAY. Only 1 of 2 available Ethernet interfaces can be used in time (ETH – RJ45 or SFP adapter).

(9) PTP

Above (red colour) marked block defines PTP Clock parameters described in Precision Time Protocol standardization IEEE1588:2008 document. This specification is well done, so there are no reasons to repeat it in this manual. For the std. server operation PTP always claim to work Ordinary. In some specific cases PTP card can be configured Boundary. The Boundary mode can be selected when clock is synchronization via PTP/Ethernet and it provides synchronization to PTP/Ethernet. In such mode the Slave only option should be selected too. We recommend to keep default Two step

<enable> and 128 Priority default set to 128 since those are most std. PTP figures to keep compatibility close.

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There are two PTP delay measurement Mechanisms:

End-To-End (E2E - default)

Peer-To-Peer (P2P)

The Peer-To-Peer (P2P) delay measurement mechanism is best in IT engineered network, where all switches can be guaranteed to be IEEE1588:2008 capable (either transparent clocks or boundary clocks). If there are going to be any non-PTPv2/IEEE1588 aware switches, or if there is any doubt about this, then please use End-To-End (E2E) delay measurement mechanism. This is why E2E is also the default mechanism at NTS-5000.

The Precision Time Protocol (PTPv2/IEEE1588:2008) works by exchanging messages between master clocks and slave clock.

E2E mechanism

Above (right side) sequence diagram is showing the exchange of messages between a PTP master clock and a PTP save clock. For NTS-5000 this process is independent for each of max. 4 PTP masters. The departure and arrival times of the Sync and Delay Request messages are saved as the four timestamps t1-t4. The Follow Up and Delay Response messages are used to transport the timestamps recorded at the MCLK to the SCLK. Such information is used to adjust slave clock time on the end of these exchanges when SCLK has all four t1-t4 timestamps. It can than calculate the offset of it’s own clock with respect to the master using following delay averaging formula:

Offset = (t2 + t3 – t1 – t4) /2

The equation assumes that the time it takes for messages to go from the MCLK to SCLK, the forward delay, is the same as the time it takes for messages to go from the slave to the master, the reverse delay. There is no problem if these delays are large, just so long as they are the same. Any difference in the forward and reverse delay results in an error in determining the difference between the master clock and the slave clock.

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Why would the forward and reverse delays be different? It’s mainly due to all of kind of pesky queues. There are queues in the routers, there are queues in the switches, there are even queues in the network stacks at the end devices. Usually messages spend minimal time in the queues, but sometimes they are waiting for a switch to finish up with other messages on the same port, or for an operating system to complete what it was doing so it can fetch a timestamp. In some cases, the delay can be quite long (to long), many microseconds, or even milliseconds. So obviously if this happens in the one direction, but not the other providing to a big time transfer error.

Basically this is all solved with hardware timestamping when messages depart from or arrive at a network port, special hardware generates a timestamp from the local clock, usually in the media independent interface between the data link layer (MAC) and the physical layer (PHY). That removes the unpredictably slow response of the operating system (OS) and other software (APP, DEV-driver etc). Switches and routers which are PTP aware also timestamp PTP messages. One type of such devices, is called a transparent clock works by updating PTP messages to correct for time spent in the device. Another type, called a boundary clock uses the PTP messages to set its own clock, then sends its time to PTP slaves which need it. This delay measurement mechanism is known as the End-to-End delay measurement mechanism. As it turns out PTP has an alternative delay measurement mechanism known as the Peer-to-Peer mechanism.

In Peer-To-Peer networks the master still sends Sync and Follow Up messages to the slave clock just as with the end-to-end delay measurement mechanism. With peer-to-peer the slave calculates its clock offset with respect to the master as follows:

slave time = master time + network delay

No need to combine four timestamps like we did with End-To-End networks. But how did the slave know the network delay? That is the Peer-To -Peer delay measurement. Instead of sending delay measurement messages from the slave to the master, as with the end-to-end approach, each device on the network exchanges peer-delay measurement messages. That way each device can keep track of the delays between itself and its immediately connected neighbors. Each device periodically initiates an exchange of peer-delay messages on every connected port. Then each device removes the peer-delay from Sync messages when it enters the device, by updating the correction field in either the Sync or Follow Up message. If it is a switch, it doesn’t include the peer-delay in the outgoing cable, even though it also knows that. The next device in the chain will do that correction, and we don’t want to double count. The sequence of peer-delay compared to E2E looks:

If in P2P model the SCLK wants to know the delay to MCLK, it sends a Pdelay Req messages, short for peer-delay request. SCLK also saves the time it sent in t1 message. MCLK saves the time of its clock, when t2 message arrives. Then the MCLK sends a PDelay Resp message, short for peerdelay response, and a Pdelay Resp Follow Up. The Follow Up message contains the departure time for the Pdelay Resp, t3. SCLK also saves the arrival time of the Pdelay Resp, t4, so it has all of four timestamps and can calculate the delay between the clocks. Here, as with the end-to-end

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mechanism, the assumption is made that the time it takes for the peer-delay messages to get from one clock to the other is the same in each direction. In the peer-to-peer case we only making that assumption over a cable, not the whole network, and there are no queues. So unless the cable is very long, that is a good assumption.

What about the queues in the switches? At the beginning of this post I said that peer-to-peer only works well when every switch is either a transparent clock or a boundary clock. That way the switch will take care of its own queuing delays. Another reason that we don’t use peer-delay with ordinary switches is that the switches don’t know what to do with peer-delay messages, and will not respond to them.

Although the end-to-end mechanism is more versatile, because it can handle ordinary switches and routers, the peer-to-peer mechanism has several advantages in networks where it does work:

• All links are periodically measured, so delay between the master and slave are already known when the network path changes. Note that peer-delay messages are exchanged even on ports blocked to prevent loops, such as by the Rapid Spanning Tree Protocol.

• There is no chance of Sync and Delay_Request messages taking different paths, since there are no Delay_Request messages.

• There is no need to worry about the master clocks ability to respond to Delay_Request messages when there are a lot of slaves, it only has to send the Sync and Follow_Up.

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SMF (UTC System Monitoring Facility for PTP)

Configuring ultra-high precision PTP the SMF (UTC Time System Monitoring Facility) should be taken into account in case of providing independent auditor UTC synchronization validation at slave.

To continuously trace slave clock offset to ref. UTC please use selected 1PPS-outputs of:

• UTC ref. (GPS receiver or local atomic clock)

• NTS-5000 Master 1PPS_output

• Slave card 1PPS-Output

In case of HFT Financial Systems such offset report should be stored in data LOG files cryptographically sealed and timestamped (rfc3161).

More detailed information about precision UTC monitoring facility you can find at www.demetratime.eu ELPROMA is member of DEMETRA project and consortium.!

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32. Application!notes!for!HFT!&!MiFID!II!

Below scheme presents recommendation of UTC time distribution via PTP based on NTS5000 HFT equipped with 4x PTPv2/IEEE1588 hardware cards. Solution warranties following properties:

1) All traders work in same UTC time domain (robust synchronization)

2) Mulit source time ref. provides robust UTC synchronization. Time is driven simultaneously from GNSS and NTA (NMI).

3) Each trader has own independent PTPv2/IEEE1588 synchronization line, so traders cannot interfere each other synchronization (traffic problem and its impact to PTP). Each trader PTP synchronization creates kind of “synchronization umwelt”. Each PTP Master has own IP stack, own OS driven. There is no communication between PTP masters inside NTS-5000. The Grand Master NTS-5000 supports synchronization to all trader “synchronization umwelts” – and they all work in same UTC time domain powered by robust synchronization.

4) Each trader PTP slave should consider to support:

a) NIC 1PPS-out for hardware monitoring (SDH). 1PPS-output should be considered to be

compared to ref. 1PPS(k). All monitored data, incl. transaction LOG should be cryptographically timestamped RFC3161

b) Solution can be considered to use software level NTP/PTP monitoring (e.g. FSMlab Time

Keeper). This is independent on NTA 1PPS hardware validation. All output audit data should be stored in LOG files, cryptographically RFC3161 timestamped, and archved for future AUDIT.

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Example$of$Stock$Exchange$HFT$synchronization$system$supporting$4$high$speed$traders$

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