Cisco Small Business
SPA2102, SPA3102, SPA8000, SPA8800, PAP2T
Analog Telephone Adapters
ADMINISTRATION
GUIDE
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Introducing Cisco Small Business Analog
Telephone Adapters
This guide describes the administration and use of Cisco Small Business analog
telephone adapters (ATAs). These ATA devices are a key element in the end-toend IP Telephony solution. An ATA device provides user access to Internet phone
services through one or more standard telephone RJ-11 phone ports using
standard analog telephone equipment. The ATA device connects to a wide area IP
network, such as the Internet, through a broadband (DSL or cable) modem or
router. The ATA can be used with an onsite call-control system such as the
SPA9000 Voice System or legacy PBX, or with an Internet-based call-control
system.
Figure1 ATA Deployment without Onsite Call Control
1
V
V
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V
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1
V
V
ComparisonofATADevices
EachATAdeviceisanintelligent low-density Voice over IP (VoIP) gateway that
enablescarrier-classresidential and business IP Telephony services delivered
overbroadbandorhigh-speed Internet connections. An ATA device maintains the
stateofeachcallitterminates and makes the proper reaction to user input events
(suchason/offhookorhook flash). The ATA devices use the Session Initiation
Protocol(SIP)openstandard so there is little or no involvement by a middle-man
serverormediagatewaycontroller. SIP allows interoperation with all ITSPs that
supportSIP.
TheATAModelstablesummarizes the ports and features provided by the ATA
devices described in this document.
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Introducing Cisco Small Business Analog Telephone Adapters
Comparison of ATA Devices
ATA Models
1
Product
Name
PAP2T21 2Voice adapter with two FXS ports.
SPA210221 12Voice adapter with router.
SPA3102111 11Voice adapter with router and PSTN
SPA800081Maintenance
SPA8800441Maintenance
FXS
(Analog
Phone)
FXO
PSTN
RJ-45
Internet
(WAN)
RJ-45
Ethernet
(LAN)
only
only
Voice
Lines
8Voice adapter with support for up to
8Voice adapter with support for up to
Description
connectivity.
eight FXS devices. Supports SIP
Trunking for inbound call routing to
trunk groups. Also has a single multiport RJ-21 50-pin connector for
optional patch-panel connectivity.
four FXS phones and up to four FXO
PSTN lines. Also has a single multiport RJ-21 50-pin connector for
optionalpatch-panelconnectivity.
Introducing Cisco Small Business Analog Telephone Adapters
Comparison of ATA Devices
The following figure illustrates how the different ATA devices provide voice
connectivity in a VoIP network.
Figure 3How ATAs Provide Voice Connectivity
1
SPA2102
SPA3102
The PAP2T and the SPA8000 provide FXS ports to connect fax machines and
analog phones to IP telephone services.
The SPA3102 and the SPA8800 act as SIP-PSTN gateways.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Connectivity Requirements
NOTE For information about the WRP400, see the WRP400 Administration Guide.
ATA Connectivity Requirements
An ATA device can be connected to a local router, or directly to the Internet. Each
phone connected to an RJ-11 (analog) port on the ATA device connects to other
devices through SIP, which is transmitted over the IP network.
In order to ensure connectivity between the devices connected to its FXS ports,
the ATA device requires the following functionality to be supplied on the network
connected to its Ethernet port:
1
Connection to an IP router with hairpinning support
Connection to an outbound Proxy server
When a phone connected to the ATA device communicates with another phone, it
sends a SIP packet onto the internal LAN. The packet is then forwarded to the
external LAN or directly to the Internet. The source address and source port on the
original packet are assigned by the ATA device DHCP server. The address and
port are translated by the ATA device using Network Address Translation (NAT)
and Port Address Translation (PAT). The packet is then routed back to the internal
network on the ATA device by the local router or the ISP router.
Problems can occur with calls between phones connected to the ATA device
when an outbound proxy or a router with hairpinning support is not available. The
ATA device cannot directly connect the two telephone devices, but requires a
local or remote router to route the packet back to its destination on the local
network from which it originated.
The necessary routing can be provided by a router with hairpinning support, or by
an outbound SIP proxy, which is typically provided by the Internet Telephony
Service Provider (ITSP). When relying on the ITSP for interconnecting phones on
the ATA device, local phones connected to the ATA device are unable to
communicate with each other if the Internet connection is not available for any
reason. It is recommended you connect the ATA device to a local router that
provides hairpinning support to prevent this problem.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Connectivity Requirements
PAP2T Connectivity
As shown in the following figure, the PAP2T has two FXS ports (voice lines 1 and
2).
1
IP
IP
NOTE
The IVR functions are accessed by connecting an analog telephone to Line 1.
For proper operation, the service provider should use an Outbound Proxy to
forward all voice traffic when the PAP2T is located behind a router. If
necessary, explicit port ranges can be specified for SIP and RTP.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Connectivity Requirements
SPA2102 Connectivity
As shown in the following illustration, the SPA2102 has two FXS ports (voice lines
1 and 2).
IP
IP
1
NOTE
By default, the device attached to the LAN port is assigned the network address
192.168.0.0 with a subnet mask of 255.255.255.0. If there is a network address
conflict with a device on the Ethernet port, the network address of the device on
the LAN port is automatically changed to 192.168.1.0.
The IVR functions are accessed by connecting an analog telephone to Line 1.
For proper operation, the service provider should use an Outbound Proxy to
forward all voice traffic when the SPA2102 is located behind a router. If
necessary, explicit port ranges can be specified for SIP and RTP.
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ATA Connectivity Requirements
SPA3102 Connectivity
As shown in the following figure, the SPA3102 has one FXS port (voice line 1).
IP
IP
1
NOTE
By default, the device on the LAN port is assigned the network address
192.168.0.0 with a subnet mask of 255.255.255.0. If there is a network address
conflict with a device on the Ethernet port, the network address of the device on
the LAN port is automatically changed to 192.168.1.0.
The IVR functions are accessed by connecting an analog telephone to Line 1.
For proper operation, the service provider should use an Outbound Proxy to
forward all voice traffic when the SPA3102 is located behind a router. If
necessary, explicit port ranges can be specified for SIP and RTP.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Connectivity Requirements
SPA8000 Connectivity
As shown in the following illustration, the SPA8000 consists of eight voice ports
1
IP
IP
By default, the device on the AUX port is assigned the network address
192.168.0.0 with a subnet mask of 255.255.255.0. If there is a network address
conflict with a device on the Ethernet port, the network address of the device on
the AUX port is automatically changed to 192.168.1.0.
In the illustration, one fax machine is connected to each pair of ports to illustrate
that only one T.38 connection is supported by each of the four pairs of RJ-11 ports.
Up to four fax machines can be connected to the SPA8000 router, but they must be
distributed as shown.
Introducing Cisco Small Business Analog Telephone Adapters
ATA Connectivity Requirements
SPA8800 Connectivity
As shown in the following figure, the SPA8800 has four voice modules that each
provide 1 FXS port and 1 FXO port.
1
IP
IP
By default, the device on the LAN port is assigned the network address
192.168.0.0 with a subnet mask of 255.255.255.0. If there is a network address
conflict with a device on the Ethernet port, the network address of the device on
the LAN port is automatically changed to 192.168.1.0.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Software Features
NOTE
The IVR functions are accessed by connecting an analog telephone to Phone 1
only.
For proper operation, the service provider should use an Outbound Proxy to
forward all voice traffic when the SPA8800 is located behind a router. If
necessary, explicit port ranges can be specified for SIP and RTP.
ATA Software Features
1
The ATA device is a full featured, fully programmable phone adapter that can be
custom provisioned within a wide range of configuration parameters. This section
contains a high-level overview of features to provide a basic understanding of the
feature breadth and capabilities of the ATA device.
G.729aThe ITU G.729 voice coding algorithm is used to
G.723.1The ATA device supports the use of ITU G.723.1 audio
Description
uncompressed 64 kbps digitized voice transmission at
one through ten 5 ms voice frames per packet. This
codec provides the highest voice quality and uses the
most bandwidth of any of the available codecs.
24, 32, and 40 kbps digitized voice transmission at one
through ten 10 ms voice frames per packet. This codec
provides high voice quality.
compress digitized speech. Cisco supports G.729.
G.729a is a reduced complexity version of G.729. It
requires about half the processing power to code
G.729. The G.729 and G.729a bit streams are
compatible and interoperable, but not identical.
codec at 6.4 kbps. Up to two channels of G.723.1 can be
used simultaneously. For example, Line 1 and Line 2 can
be using G.723.1 simultaneously, or Line 1 or Line 2 can
initiate a three-way conference with both call legs using
G.723.1.
NOTE When no static payload value is assigned per RFC 1890, the ATA device can
support dynamic payloads for G.726.
SIP Proxy Redundancy
In typical commercial IP Telephony deployments, all calls are established through
a SIP proxy server. An average SIP proxy server may handle thousands of
subscribers. It is important that a backup server be available so that an active
server can be temporarily switched out for maintenance. The ATA device supports
the use of backup SIP proxy servers (via DNS SRV) so that service disruption
should be nearly eliminated.
Introducing Cisco Small Business Analog Telephone Adapters
ATA Software Features
FeatureDescription
1
Modem and Fax
Pass-Through
Adaptive Jitter
Buffer
Modem pass-through mode can be triggered only by
predialing the number set in the
(Set in the Regional tab.)
FAX pass-through mode is triggered by a CED/CNG tone or
an NSE event.
Echo canceller is automatically disabled for Modem pass-
through mode.
Echo canceller is disabled for FAX pass-through if the
parameter (Line 1 or 2 tab) is set to yes
for that line (in that case FAX pass-through is the same as
Modem pass-through).
Call waiting and silence suppression is automatically
disabled for both FAX and Modem pass-through. In addition,
out-of-band DTMF Tx is disabled during modem or fax passthrough.
The ATA device can buffer incoming voice packets to
minimize out-of-order packet arrival. This process is
known as jitter buffering. The jitter buffer size proactively
adjusts or adapts in size, depending on changing network
conditions.
Introducing Cisco Small Business Analog Telephone Adapters
ATA Software Features
FeatureDescription
1
Register Retry
Enhancements
The Register Retry Enhancements feature for SPA2102,
SPA3102, and PAP2T devices adds flexibility to the delay
timers that are activated when the SIP REGISTER of a
device fails. Once a SIP REGISTER failure response code
is sent, a delay timer is selected depending on the type of
registration failure response code. The delay timers can
be one of the following:
Reg Retry Random DelayRandom delay range (in
seconds) to add to the Register Retry Intvl parameter when
retrying a SIP REGISTER after a failure. The default is 0,
which disables this feature.
Reg Retry Long Random DelayRandom delay range (in
seconds) to add to the Register Retry Long Intvl parameter
when retrying a SIP REGISTER after a failure. The default is
0, which disables this feature.
Reg Retry Intvl CapThe maximum value to cap the
exponential back-off retry delay. The exponential back-off
retry delay starts with the setting found in the Register Retry
Intvl parameter and doubles it on every REGISTER retry after
a failure. In other words, the retry interval after a failure is
alwayssettothesecondsconfiguredintheRegisterRetryIntvlparameter.Ifthisfeatureisenabled,theRegRetryRandomDelaysettingisaddedontopoftheexponentialback-offadjusteddelayvalue.Thedefaultvalueis0,whichdisablestheexponentialback-offfeature.
RegisterRetryisconfiguredintheSIPtab.SeeATAVoice
FieldReference,onpage110.
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Introducing Cisco Small Business Analog Telephone Adapters
ATA Software Features
FeatureDescription
1
DHCP Renewal on
Timeout
SPA2102, SPA3102, and PAP2T voice devices typically
operate in a network where a DHCP server assigns IP
addresses to the devices. Because IP addresses are a
limited resource, the DHCP server periodically renews the
device lease on the IP address. Therefore, if an ATA device
loses its IP address for any reason, or if some other device
on the network is assigned its IP address, the
communication between the SIP proxy and the device is
either severed or degraded.
Whenever an expected SIP response is not received
within a programmable amount of time after the
corresponding SIP command is sent, the DHCP Renewal
on Timeout feature automatically causes the device to
request a renewal of its IP address. If the DHCP server
returns the IP address that it originally assigned to the
device, the ATA device is presumed to be operating
correctly. If it returns a different address, the ATA device
changes its IP address to the new address provided by
the DHCP server. The ATA device then resets, and once
again sends a SIP register request for the DHCP server to
accept.
See your the Quick Installation Guide and the User Guide for the ATA model that
you are installing. If you are configuring the complete SPA9000 Voice System, also
refer to the documentation for the SPA9000 Voice System.
Upgrading the Firmware for the ATA Device
In this procedure, you install the firmware files that you downloaded previously.
STEP 1 Determine the address of the ATA device:
a. Connect an analog telephone to the Phone 1 or Phone 2 port on the ATA
device. (You may not hear a dial tone. Continue to step b.)
b. Press on the keypad to access the IVR menu.
c. Press to determine the Internet (WAN) IP address.
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Basic Administration and Configuration
Setting up Your ATA Device
STEP 2 Make a note of the IP address that is announced.
NOTE If the administration computer is connected to the Ethernet port of the ATA
device, the default IP address is 192.168.0.1.
STEP 3 Use the administration computer to install the latest firmware:
a. Extract the Zip file, and then run the executable file to upgrade the firmware.
b. When the window appears, click .
c. In the next window that appears, enter the IP address of the ATA device, and
then click .
d. In the window, verify that the correct device information and
product number appear. Then click .
2
e. A progress message appears while the upgrade is in progress. The success
window appears when the upgrade is completed. The device reboots.
f.Click to close the confirmation message.
g. To verify the upgrade, point the web browser to the IP address of the ATA
device. Check the page. The field should
show the firmware version that you installed.
NOTE You may need to refresh your browser to display the updated page
reflecting the new version number.
Setting up Your ATA Device
After installation and basic configuration of your ATA device, you will use the
administration web server to finish your configuration.
ATA devices support two levels of administration privileges: Administrator and
User. Both privileges can be password protected.
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Basic Administration and Configuration
Using the Administration Web Server
NOTE By default, there are no passwords assigned for either the Administrator account or
the User account.
The Administrator account can modify all the web profile parameters and the
passwords of both Administrator and User account. The User account can access
only part of the web profile parameters. The parameters that the User account can
access are specified using the Administrator account on the Provisioning page of
the administration web server.
To directly access the Administrator account level privilege, use the following URL:
http://<ipaddress>/admin/voice
If the password has been set for the Administrator account, the browser prompts
for authentication. The User account name and the Administrator account name
cannot be changed.
2
When browsing pages with the Administrator account privilege, you can switch to
User account privilege by clicking the link.
User Guide for your device, or the LVS Administration Guide.
STEP 3 Direct the browser to the IP address of the ATA device.
STEP 4 The page appears. By default, the page is in Basic User mode. Log
on to the administrator view by clicking , near the top right corner of
the page. Then click .
NOTE By default, no password is required. You can assign an administrative
password later, but it is convenient not to use a password during the initial
configuration.
Setting Up the WAN Configuration for Your ATA Device
STEP 1 Start Internet Explorer, connect to the administration web server, and choose
Admin access with Advanced settings.
STEP 2 Click Network tab > WAN Setup.
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Basic Administration and Configuration
Using the Administration Web Server
STEP 3 Complete the WAN configuration for DHCP, static IP addressing, or PPPoE.
For DHCP:
a. Select DHCP from the drop-down menu.
b. If you use a cable modem, you may need to configure the MAC Clone Settings.
(Contact your ISP for more information.)
c. If your service uses a specific PC MAC address, then select yes from the
d. Then enter the PCs MAC address in the field.
For Static IP Addressing:
a. Select Static IP from the drop-down menu.
b. In the Static IP Settings section, enter the IP address in the field, the
subnet mask in the field, and the default gateway IP address in the
field.
2
setting.
c. In the Optional Settings section, enter the DNS server address(es) in the
and optional fields.
For PPPoE:
a. Select PPPoE from the drop-down menu. This is the correct
setting for most DSL users.
b. Enter the values provided by the ITSP in the following fields:
PPPoE Login Name
PPPoE Login Password
PPPoE Service Name
STEP 4 Click . The ATA device reboots.
STEP 5 To verify your progress, click the tab and then click . Under
, confirm the , , ,
, and .
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Basic Administration and Configuration
Using the Administration Web Server
Registering to the Service Provider
To use VoIP phone service, you must configure your ATA device to the Service
Provider.
STEP 1 Start Internet Explorer, connect to the administration web server, and choose
Admin access with Advanced settings.
STEP 2 Click Voice tab > Line , where is the line number that you want to configure.
STEP 3 Enter the account information for your ITSP. The following is the minimum required
configuration to connect the ATA device to an ITSP:
User ID: The account number or logon name for your ITSP account (Subscriber
Information section)
Password: The password for your ITSP account (Subscriber Information
section)
2
Proxy: The proxy server for your ITSP account (Proxy and Registration section)
STEP 4 After making any necessary changes, click the Submit All Changes button.
STEP 5 To verify your progress, perform the following tasks:
After the devices reboot, click Voice tab > Info. Scroll down to the
section of the page. Verify that the line is registered.
Use an external phone to place an inbound call to the telephone number that
was assigned by your ITSP. Assuming that you have left the default settings in
place, the phone should ring and you can pick up the phone to get two-way
audio.
If the line is not registered, you may need to refresh the browser several times
because it can take a few seconds for the registration to succeed. Also verify
that your DNS is configured properly.
NOTE If the device has more than one Line tab, each line tab must be configured
separately. Each line tab can be configured for a different ITSP.
Upgrading, Rebooting, and Resyncing Your ATA Device
The administration web server supports upgrading, rebooting, and resyncing
functions through special URLs. Administrator account privilege is needed for
these functions.
Upgrade URL
The Upgrade URL lets you upgrade the ATA device to the firmware specified by
the URL, which can identify either a TFTP or HTTP server.
NOTE If the value of the parameter in the Provisioning page is No, you
cannot upgrade the ATA device even if the web page indicates otherwise.
The syntax of the Upgrade URL is as follows:
Both HTTP and TFTP are supported for the upgrade operation.
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Upgrading, Rebooting, and Resyncing Your ATA Device
If no is specified, TFTP is assumed. If no is specified, the
host that requests the URL is used as .
If no port specified, the default port of the protocol is used. (69 for TFTP or 80 for
HTTP)
The is typically the file name of the binary located in a
directory on the TFTP or HTTP server. If no is specified,
is assumed, as in the following example:
Resync URL
The Resync URL lets you force the ATA device to do a resync to a profile specified
in the URL, which can identify either a TFTP, HTTP, or HTTPS server. The syntax of
the Resync URL is as follows:
2
NOTE The SPA resyncs only when it is idle.
If no parameter follows the Profile Rule setting from the Provisioning
page is used.
If no is specified, TFTP is assumed. If no is specified, the
host that requests the URL is used as
If no port is specified, the default port is used (69 for TFTP, 80 for HTTP, and 443
for HTTPS).
The profile-path is the path to the new profile with which to resync, for example:
Reboot URL
The Reboot URL lets you reboot the ATA device. The Reboot URL is as follows:
The ATA configuration profile can be either an XML file or a binary file with a
proprietary format.
The XML file consists of a series of elements (one per configuration parameter),
encapsulated within the element tags <flat-profile> </flat-profile>. The
encapsulated elements specify values for individual parameters. Here is an
example of a valid XML profile:
Binary format profiles contain ATA parameter values and user access permissions
for the parameters. By convention, the profile uses the extension .cfg (for example,
spa2102.cfg). The Profile Compiler (SPC) tool compiles a plain-text file containing
parameter-value pairs into a properly formatted and encrypted .cfg file. The SPC
tool is available for the Win32 environment and Linux-i386-elf environment.
Requests for SPC tools compiled on other platforms are evaluated on a case-bycase basis. Please contact your sales representative for further information about
obtaining the SPC tool.
2
The syntax of the plain-text file accepted by the profile compiler is a series of
parameter-value pairs, with the value in double quotes. Each parameter-value pair
is followed by a semicolon. Here is an example of a valid text source profile for
input to the SPC tool:
Refer to the SPA Provisioning Guide for further details.
The names of parameters in XML profiles can generally be inferred from the ATA
configuration Web pages, by substituting underscores (_) for spaces and other
control characters. Further, to distinguish between Lines 1, 2, 3, and 4,
corresponding parameter names are augmented by the strings _1_, _2_, _3_, and
_4_. For example, Line 1 Proxy is named Proxy_1_ in XML profiles.
Parameters in the case of source text files for the SPC tool are similarly named,
except that to differentiate Line 1, 2, 3, and 4, the appended strings ([1], [2], [3], or
[4]) are used. For example, the Line 1 Proxy is named Proxy[1] in source text
profiles for input to the SPC.
Network Address Translation (NAT) and Voice over IP (VoIP)
NAT Mapping with Session Border Controller
It is strongly recommended that you choose an ITSP that supports NAT mapping
through a Session Border Controller. With NAT mapping provided by the ITSP, you
have more choices in selecting a router.
NAT Mapping with SIP-ALG Router
If the ITSP network does not provide a Session Border Controller functionality, you
can achieve NAT mapping by using a router that has a SIP ALG (Application Layer
Gateway). The WRV200 router is recommended for this purpose, although any
router with a SIP-ALG can be used. By using a SIP-ALG router, you have more
choices in selecting an ITSP.
3
Configuring NAT Mapping with a Static IP Address
If the ITSP network does not provide a Session Border Controller functionality, and
if other requirements are met, you can configure NAT mapping to ensure
interoperability with the ITSP.
Network Address Translation (NAT) and Voice over IP (VoIP)
Determining the Routers NAT Mechanism
STUN does not work on routers with symmetric NAT. With symmetric NAT, IP
addresses are mapped from one internal IP address and port to one external,
routable destination IP address and port. If another packet is sent from the same
source IP address and port to a different destination, then a different IP address
and port number combination is used. This method is restrictive because an
external host can send a packet to a particular port on the internal host only if the
internal host first sent a packet from that port to the external host.
NOTE This procedure assumes that a syslog server is configured and is ready to receive
syslog messages.
STEP 1 Make sure you do not have firewall running on your PC that could block the syslog
port (port 514 by default).
3
STEP 2 Connect to the administration web server, and choose Admin access with
Advanced settings.
STEP 3 To enable debugging, complete the following tasks:
a. Click Voice tab > System.
b. In the Debug Server field, enter the IP address of your syslog server. This
address and port number must be reachable from the SPA9000.
c. From the Debug level drop-down list, choose 3.
STEP 4 To collect information about the type of NAT your router is using, complete the
following tasks:
a. Click Voice tab > SIP.
b. Scroll down to the NAT Support Parameters section.
c. From the STUN Test Enable field, choose yes.
STEP 5 To enable SIP signalling, complete the following task:
a. Click Voice tab > Line , where N represents the line interface number.
b. In the SIP Settings section, choose full from the SIP Debug Option field.
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Configuring Your System for ITSP Interoperability
Firewalls and SIP
STEP 6 Click Submit All Changes.
STEP 7 View the syslog messages to determine whether your network uses symmetric
NAT. Look for a warning header in the REGISTER messages, such as Warning: 399
spa "Full Cone NAT Detected.
Firewalls and SIP
To enable SIP requests and responses to be exchanged with the SIP proxy at the
ITSP, you must ensure that your firewall allows both SIP and RTP unimpeded
access to the Internet.
Make sure that the following ports are not blocked:
3
SIP portsUDP port 5060 through 5063, which are used for the ITSP line
You can connect a fax machine to an FXS port on the SPA2102, SPA3102,
SPA8000, and SPA8800. T.38 Fax is supported on these devices, for fax
transmission over an IP network. The SPA2102 and SPA3102 support a single
connection, while the SPA8000 and SPA8800 support one connection for each
pair of FXS ports (1/2, 3/4, 5/6, and 7/8) for a maximum of four connections.
Follow this procedure to optimize fax completion rates.
4
STEP 1 Upgrade the ATA firmware to the latest version
STEP 2 Ensure that you have enough bandwidth for uplink and downlink.
For G.711 fallback, it is recommend to have approximately 100Kbps.
For T.38, allocate at least 50 kbps.
STEP 3 To optimize G.711 fallback fax completion rates, set the following on the Line tab
of your ATA device:
Network Jitter Buffer: very high
Jitter buffer adjustment: disable
Call Waiting: no
3 Way Calling: no
Echo Canceller: no
Silence suppression: no
Preferred Codec: G.711
Use pref. codec only: yes
STEP 4 If you are using a Cisco media gateway for PSTN termination, disable T.38 (fax
relay) and enable fax using modem passthrough.
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Configuring Voice Services
Using a FAX Machine
For example:
STEP 5 Enable T.38 fax on the SPA 2102 by configuring the following parameter on the
Line tab for the FXS port to which the FAX machine is connected:
NOTE If a T.38 call cannot be set-up, then the call should automatically revert to
4
G.711 fallback.
STEP 6 If you are using a Cisco media gateway use the following settings:
Make sure the Cisco gateway is correctly configured for T.38 with the SPA dial
peer. For example:
Fax Troubleshooting
If have problems sending or receiving faxes, complete the following steps:
STEP 1 Verify that your fax machine is set to a speed between 7200 and 14400.
STEP 2 Send a test fax in a controlled environment between two ATAs.
STEP 3 Determine the success rate.
STEP 4 Monitor the network and record the following statistics:
The choice of caller ID (CID) method is dependent on your area/region. To
configure CID, use the following parameters:
ParameterTabDescription and Value
4
Caller ID
Method
RegionalThe following choices are available:
Bellcore (N.Amer,China)CID, CIDCW, and VMWI.
FSK sent after first ring (same as ETSI FSK sent after
first ring) (no polarity reversal or DTAS).
DTMF (Finland, Sweden)CID only. DTMF sent after
polarity reversal (and no DTAS) and before first ring.
DTMF (Denmark)CID only. DTMF sentbefore first
ring with no polarity reversal and no DTAS.
ETSI DTMFCID only. DTMF sent after DTAS (and no
polarity reversal) and before first ring.
ETSI DTMF With PRCID only. DTMF sent after
polarity reversal and DTAS and before first ring.
ETSI DTMF After RingCID only. DTMF sent after
first ring (no polarity reversal or DTAS).
ETSI FSKCID, CIDCW, and VMWI. FSK sent after
DTAS (but no polarity reversal) and before first ring.
Waits for ACK from CPE after DTAS for CIDCW.
ETSI FSK With PR (UK)CID, CIDCW, and VMWI.
FSK is sent after polarity reversal and DTAS and
before first ring. Waits for ACK from CPE after DTAS for
CIDCW. Polarity reversal is applied only if equipment
is on hook.
Caller ID
FSK
Standard
Cisco Small Business ATA Administration Guide53
Regional
DTMF (Denmark) With PRCID only. DTMF sent after
polarity reversal (and no DTAS) and before first ring.
The default is Bellcore(N.Amer, China).
The ATA device supports bell 202 and v.23
standards for caller ID generation. Select the FSK
standard you want to use, bell 202 or v.23.
The default is bell 202.
This field is not found in the PAP2T.
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Configuring Voice Services
Managing Caller ID Service
There are three types of Caller ID:
4
On Hook Caller ID Associated with Ringing This type of Caller ID is used
for incoming calls when the attached phone is on hook. See the following
figure (a) (c). All CID methods can be applied for this type of CID.
On Hook Caller ID Not Associated with Ringing This feature is used to
send VMWI signal to the phone to turn the message waiting light on and off
(see Figure 1 (d) and (e)). This is available only for FSK-based CID methods:
(Bellcore, ETSI FSK, and ETSI FSK With PR).
Off Hook Caller ID This is used to delivery caller-id on incoming calls
when the attached phone is off hook (see the following figure). This can be
call waiting caller ID (CIDCW) or to notify the user that the far end party
identity has changed or updated (such as due to a call transfer). This is
available only for FSK-based CID methods: (Bellcore, ETSI FSK, and ETSI
FSK With PR).
a) Bellcore/ETSI Onhook Post-Ring FSK
First
Ring
b) ETSI Onhook Post-Ring DTMF
First
Ring
c) ETSI Onhook Pre-Ring FSK/DTMF
Polarity
Reversal
d) Bellcore Onhook FSK w/o Ring
OSIFSK
e) ETSI Onhook FSK w/o Ring
Polarity
Reversal
CAS
(DTAS)
CAS
(DTAS)
FSK
DTMF
DTMF/
FSK
FSK
First
Ring
f) Bellcore/ETSI Offhook FSK
Cisco Small Business ATA Administration Guide54
CAS
(DTAS)
Wait For
ACK
FSK
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Configuring Voice Services
Silence Suppression and Comfort Noise Generation
Silence Suppression and ComfortNoiseGeneration
Voice Activity Detection (VAD)withSilenceSuppressionisameansofincreasing
the number of calls supportedbythenetworkbyreducingtherequiredbandwidth
for a single call. VAD uses a sophisticatedalgorithmtodistinguishbetween
speech and non-speech signals.Basedonthecurrentandpaststatistics,theVAD
algorithm decides whether ornotspeechispresent.IftheVADalgorithmdecides
speech is not present, the silencesuppressionandcomfortnoisegenerationis
activated. This is accomplishedbyremovingandnottransmittingthenatural
silence that occurs in normaltwo-wayconnection.TheIPbandwidthisusedonly
when someone is speaking. Duringthesilentperiodsofatelephonecall,additional
bandwidth is available for othervoicecallsordatatrafficbecausethesilence
packets are not being transmittedacrossthenetwork.
Comfort Noise Generation providesartificially-generatedbackgroundwhitenoise
(sounds), designed to reassurecallersthattheircallsarestillconnectedduring
silent periods. If Comfort NoiseGenerationisnotused,thecallermaythinkthecall
has been disconnected becauseofthedeadsilenceperiodscreatedbytheVAD
and Silence Suppression feature.
4
Silence suppression is configuredintheLineandPSTNLinetabs.SeeATA
Enter any of these characters to represent a key
that the user must press on the phone keypad.
Enter to represent any character on the phone
keypad.
Enter characters within square brackets to create
a list of accepted key presses. The user can press
any one of the keys in the list.
Numeric range
For example, you would enter to allow the
user to press any one digit from 2 through 9.
Numeric range with other characters
For example, you would enter
the user to press 3, 5, 6, 7, 8, or *.
4
to allow
(period)
Enter a period for element repetition. The dial plan
accepts 0 or more entries of the digit. For
example, allows users to enter 0, 01, 011,
0111, and so on.
For sequence substitution, use this format to
indicate that certain dialed digits are replaced by
other characters when the sequence is
transmitted. The digits can be zero or
more characters.
EXAMPLE 1:
When the user presses 8 followed by a sevendigit number, the system automatically replaces
the dialed 8 with 1650. If the user dials
85550112, the system transmits 16505550112.
EXAMPLE 2:
In this example, no digits are replaced. When the
user enters a 10-digit string of numbers, the
number 1 is added at the beginning of the
sequence. If the user dials 9725550112, the
system transmits 19725550112
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Configuring Dial Plans
Digit SequenceFunction
For an intersequence tone, enter a comma
(comma)
(exclamation point)
between digits to play an outside line dial tone
after a user-entered sequence.
EXAMPLE:
An outside line dial tone is sounded after the
user presses 9, and the tone continues until the
user presses 1.
For number barring, enter an exclamation point to
prohibit a dial sequence pattern.
EXAMPLE:
The system rejects any 11-digit sequence that
begins with 1900.
4
Enter an asterisk to allow the user to enter a 2digit star code.
For Interdigit Timer Master Override, enter to
reduce the short inter-digit timer to 0 seconds, or
enter L0 to reduce the long inter-digit timer to 0
seconds.
For a pause, enter followed by a number and a
space. The duration of the pause is the specified
number of seconds. This feature is typically used
for implementation of a hot line and warm line,
with 0 delay for the hot line and a non-zero delay
for a warm line.
EXAMPLE:
NOTE The SPA implicitly appends the vertical code sequences entered in the regional
parameter settings to the end of the dial plan. Likewise, if Enable_IP_Dialing is
enabled, then IP dialing is also accepted on the associated line.
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4
Digit Sequence Examples
The following examples show digit sequences that you can enter in a dial plan.
In a complete dial plan entry, sequences are separated by a pipe character (|), and
the entire set of sequences is enclosed within parentheses.
EXAMPLE:
Extensions on your system
EXAMPLE:[1-8]xx
[1-8]xx Allows a user dial any three-digit number that starts with the digits 1
through 8. If your system uses four-digit extensions, you would instead enter
the following string:
[1-8]xxx
Local dialing with seven-digit number
EXAMPLE:9, xxxxxxx
9, xxxxxxx After a user presses 9, an external dial tone sounds. The user can
enter any seven-digit number, as in a local call.
Local dialing with 3-digit area code and a 7-digit local number
EXAMPLE:9, <:1>[2-9]xxxxxxxxx
9, <:1>[2-9]xxxxxxxxx This example is useful where a local area code is required.
After a user presses 9, an external dial tone sounds. The user must enter a 10digit number that begins with a digit 2 through 9. The system automatically
inserts the 1 prefix before transmitting the number to the carrier.
Local dialing with an automatically inserted 3-digit area code
EXAMPLE:8,
<:1212>xxxxxxx
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4
8, <:1212>xxxxxxx This is example is useful where a local area code is required
by the carrier but the majority of calls go to one area code. After the user
presses 8, an external dial tone sounds. The user can enter any seven-digit
number. The system automatically inserts the 1 prefix and the 212 area code
before transmitting the number to the carrier.
U.S. long distance dialing
EXAMPLE:
9, 1 [2-9] xxxxxxxxx
9, 1 [2-9] xxxxxxxxx After the user presses 9, an external dial tone sounds. The
user can enter any 11-digit number that starts with 1 and is followed by a digit
2 through 9.
Blocked number
EXAMPLE:
9, 1 900 xxxxxxx !
9, 1 900 xxxxxxx ! This digit sequence is useful if you want to prevent users from
dialing numbers that are associated with high tolls or inappropriate content,
such as 1-900 numbers in the U.S.. After the user press 9, an external dial tone
sounds. If the user enters an 11-digit number that starts with the digits 1900,
the call is rejected.
U.S. international dialing
EXAMPLE:
9, 011xxxxxx.
9, 011xxxxxx. After the user presses 9, an external dial tone sounds. The user can
enter any number that starts with 011, as in an international call from the U.S.
Informational numbers
EXAMPLE:
9, 011xxxxxx.
0 | [49]11 This example includes two digit sequences, separated by the pipe
character. The first sequence allows a user to dial 0 for an operator. The second
sequence allows the user to enter 411 for local information or 911 for
emergency services.
0 | [49]11
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4
Acceptance and Transmission the Dialed Digits
When a user dials a series of digits, each sequence in the dial plan is tested as a
possible match. The matching sequences form a set of candidate digit sequences.
As more digits are entered by the user, the set of candidates diminishes until only
one or none are valid. When a terminating event occurs, the SPA9000 either
accepts the user-dialed sequence and initiates a call, or else rejects the sequence
as invalid. The user hears the reorder (fast busy) tone if the dialed sequence is
invalid.
The following table explains how terminating events are processed.
Terminating EventProcessing
The dialed digits do not match
any sequence in the dial plan.
The dialed digits exactly match
one sequence in the dial plan.
A timeout occurs.The number is rejected if the dialed digits are
The user presses the # key or
the dial softkey on the phone
display.
The number is rejected.
If the sequence is allowed by the dial plan, the
number is accepted and is transmitted
according to the dial plan.
If the sequence is blocked by the dial plan, the
number is rejected.
not matched to a digit sequence in the dial
plan within the time specified by the
applicable interdigit timer.
The Interdigit Long Timer applies when the
dialed digits do not match any digit sequence
in the dial plan. The default value is 10
seconds.
The Interdigit Short Timer applies when the
dialed digits match one or more candidate
sequences in the dial plan. The default value is
3 seconds.
If the sequence is complete and is allowed by
the dial plan, the number is accepted and is
transmitted according to the dial plan.
If the sequence is incomplete or is blocked by
the dial plan, the number is rejected.
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4
Dial Plan Timer (Off-Hook Timer)
You can think of the Dial Plan Timer as the off-hook timer. This timer starts
counting when the phone goes off hook. If no digits are dialed within the specified
number of seconds, the timer expires and the null entry is evaluated. Unless you
have a special dial plan string to allow a null entry, the call is rejected. The default
value is 5.
Syntax for the Dial Plan Timer
SYNTAX: s
s: The number of seconds; if no number is entered after , the default timer of 5
seconds applies.
n: (optional): The number to transmit automatically when the timer expires; you
can enter an extension number or a DID number. No wildcard characters are
allowed because the number will be transmitted as shown. If you omit the
number substitution, <:n>, then the user hears a reorder (fast busy) tone after
the specified number of seconds.
Examples for the Dial Plan Timer
Allow more time for users to start dialing after taking a phone off hook.
EXAMPLE: P9
P9 After taking a phone off hook, a user has 9 seconds to begin dialing. If no
digits are pressed within 9 seconds, the user hears a reorder (fast busy) tone.
By setting a longer timer, you allow more time for users to enter the digits.
Create a hotline for all sequences on the System Dial Plan
EXAMPLE: P9<:23>
P9<:23> After taking the phone off hook, a user has 9 seconds to begin dialing. If
no digits are pressed within 9 seconds, the call is transmitted automatically to
extension 23.
Create a hotline on a line button for an extension
EXAMPLE: ( P0 <:1000>)
With the timer set to 0 seconds, the call is transmitted automatically to the
specified extension when the phone goes off hook. Enter this sequence in the
Phone Dial Plan for Ext 2 or higher on a client station.
Note that the timer sequence appears to the left of the initial parenthesis for the
dial plan.
Example for the Interdigit Long Timer
EXAMPLE: L:15,
L:15, This dial plan allows the user to pause for up to 15 seconds between digits
before the Interdigit Long Timer expires. This setting is especially helpful to users
such as sales people, who are reading the numbers from business cards and other
printed materials while dialing.
Interdigit Short Timer (Complete Entry Timer)
You can think of this timer as the complete entry timer. This timer measures the
interval between dialed digits. It applies when the dialed digits match at least one
digit sequence in the dial plan. Unless the user enters another digit within the
specified number of seconds, the entry is evaluated. If it is valid, the call proceeds.
If it is invalid, the call is rejected. The default value is 3 seconds.
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4
Syntax for the Interdigit Short Timer
SYNTAX 1: :s,
Use this syntax to apply the new setting to the entire dial plan within the
parentheses.
SYNTAX 2: sequence
Use this syntax to apply the new setting to a particular dialing sequence.
s: The number of seconds; if no number is entered after , the default timer of 5
seconds applies.
Examples for the Interdigit Short Timer
Set the timer for the entire dial plan.
EXAMPLE: S:6,
S:6, While entering a number with the phone off hook, a user can pause for up
to 15 seconds between digits before the Interdigit Short Timer expires. This
setting is especially helpful to users such as sales people, who are reading the
numbers from business cards and other printed materials while dialing.
Set an instant timer for a particular sequence within the dial plan.
EXAMPLE: 9,8,1[2-9]xxxxxxxxxS0
9,8,1[2-9]xxxxxxxxxS0 With the timer set to 0, the call is transmitted automatically
when the user dials the final digit in the sequence.
A secure call is established in two stages. The first stage is no different from
normal call setup. The second stage starts after the call is established in the
normal way with both sides ready to stream RTP packets.
In the second stage, the two parties exchange information to determine if the
current call can switch over to the secure mode. The information is transported by
base64 encoding embedded in the message body of SIP INFO requests, and
responses using a proprietary format. If the second stage is successful, the ATA
device plays a special Secure Call Indication Tone for a short time to indicate to
both parties that the call is secured and that RTP traffic in both directions is being
encrypted.
If the user has a phone that supports call waiting caller ID (CIDCW) and that
service is enabled, the CID will be updated with the information extracted from the
Mini-Certificate received from the remote party. The Name field of the CID will be
prepended with a $ symbol. Both parties can verify the name and number to
ensure the identity of the remote party.
The signing agent is implicit and must be the same for all ATAs that communicate
securely with each other. The public key of the signing agent is pre-configured into
the ATA device by the administrator and is used by the ATA device to verify the
Mini-Certificate of its peer. The Mini-Certificate is valid if it has not expired, and it
has a valid signature.
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Secure Call Implementation
4
The ATA device can be configured so that, by default, all outbound calls are either
secure or not secure. If secure by default, the user has the option to disable
security when making a call by dialing *19 before dialing the target number. If not
secure by default, the user can make a secure outbound call by dialing *18 before
dialing the target number. However, the user cannot force inbound calls to be
secure or not secure; that depends on whether the caller has security enabled or
not.
The ATA device will not switch to secure mode if the CID of the called party from
its Mini-Certificate does not agree with the user-id used in making the outbound
call. The ATA device performs this check after receiving the Mini-Certificate of the
called party
Secure Call Details
Looking at the second stage of setting up a secure call in greater detail, this stage
can be further divided into two steps.
STEP 1 The caller sends a Caller Hello message (base64 encoded and embedded in the
message body of a SIP INFO request) to the called party with the following
information:
Message ID (4B)
Version and flags (4B)
SSRC of the encrypted stream (4B)
Mini-Certificate (252B)
Upon receiving the Caller Hello, the called party responds with a Callee Hello
message (base64 encoded and embedded in the message body of a SIP
response to the callers INFO request) with similar information, if the Caller Hello
message is valid. The caller then examines the Callee Hello and proceeds to the
next step if the message is valid.
STEP 2 The caller sends the Caller Final message to the called party with the following
information:
Message ID (4B)
Encrypted Master Key (16B or 128b)
Encrypted Master Salt (16B or 128b)
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Using a Mini-Certificate
The Master Key and Master Salt are encrypted with the public key from the called
party mini-certificate. The Master Key and Master Salt are used by both ends for
deriving session keys to encrypt subsequent RTP packets. The called party then
responds with a Callee Final message (which is an empty message).
The Mini-Certificate (MC) contains the following information:
User Name (32B)
User ID or Phone Number (16B)
Expiration Date (12B)
Public Key (512b or 64B)
Signature (1024b or 512B)
The MC has a 512-bit public key used for establishing secure calls. The
administrator must provision each subscriber of the secure call service with an
MC and the corresponding 512-bit private key. The MC is signed with a 1024-bit
private key of the service provider, which acts as the CA of the MC. The 1024-bit
public key of the CA signing the MC must also be provisioned for each subscriber.
The SIP Trunking feature allows a traditional PBX to seamlessly migrate from
PSTN service to VoIP service over a broadband link. The SPA8000 offers up to
eight telephone lines to the PBX.
4
The SPA8000 offers four trunk groups, numbered T1, T2, T3, and T4. A SIP-based
voice service with an ITSP can be configured on each trunk group with a distinct
phone number. Each of the eight SPA8000 lines can be configured either as a
standalone line, as in a classic ATA FXS port, or as a trunk line that is associated
with a trunk group.
Inbound calling: A trunk group offers a single number for callers to call into the
small business, with the capability to programmatically ring one or more trunk
lines.
Outbound calling: When a PBX phone makes a call, the PBX selects one of the
available trunk lines. The trunk line assumes the Caller ID of the trunk group.
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SIP Trunking and Hunt Groups on the SPA8000
The following figure shows a simplified logical block diagram of the SPA8000 with
the SIP Trunking feature.
Figure1 Logical Block Diagram of SIP Trunking
4
SIP Path: As a standalone line, the SIP User Agent (SIP UA) exchanges signaling
directly with the ITSP equipment. As a trunk line, the Line UA exchanges
signaling with the internal proxy server only. The Internal Proxy Server handles
all SIP signalling between both ends of the call, from call establishment to
termination.
RTP Path: Whether the line is standalone or a member of a trunk group, the Line
UA exchanges RTP packets directly with the ITSP equipment.
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NOTE Although the figure shows only one ITSP account, each standalone line and each
Trunk Group can be configured with a different ITSP (with some limitations applied).
Setting the Trunk Group Call Capacity
The ITSP may set a limit to the number of calls that can be made on a trunk group.
You can configure a trunk groups call capacity parameter to meet the
requirements of the ITSP. Both incoming call and outgoing calls are counted
towards this limit. The call capacity has the following impact on call handling:
Inbound calls: When the limit is reached, the Trunk UA replies 486 to the
caller.
Outbound calls: When the limit is reached, the Line UA plays a fast busy
tone to the caller. Note that a trunk line can make an outgoing call only
through its own trunk. If that trunk reaches full capacity, it will not attempt to
failover to use other trunks.
4
You can configure this setting in the Voice tab > Trunk (T1 ... T4) page, Subscriber
Informationsection,CallCapacityfield.Formoreinformation,seeConfiguringa
STEP 5 If the call is picked up by the PBX, the Line UA replies 200 OK with SDP to the
internal Proxy. The Trunk UA in turn replies 200 OK to the ITSP and relay the Line
SDP in the 200 OK message also. If all goes well, the Line UA and the ITSP
equipment start exchanging RTP packets afterwards.
Contact List for a Trunk Group
The hunting process for incoming calls is controlled by the Contact List. The
Contact List specifies the lines to ring, the order in which to ring them, the duration
to ring one line before trying another line, and the maximum period to hunt. Below,
the syntax is described and examples are provided to help you to configure the
Contact List for each trunk group.
SYNTAX:
: The line numbers (1 - 8), or a wildcard * or ? to represent all lines.
4
The Trunk UA rings only trunk lines, that is, lines that are assigned to a trunk
group through the Voice tab > Line page, Trunk Group field. The Trunk UA
does not ring any standalone lines that are included in the Contact List. The
TrunkUAringsanytrunklinethatisincludedinthelist,evenifitisnotassignedtotheparticulartrunkgroupforthisContactList.
below), the hunt proceeds randomly through the unchosen lines until
each line is tried.
-: All. The Trunk UA rings all the lines at the same time.
: The number of seconds to wait for one line to answer, before
choosing another line. If interval is *, the hunt is stopped at the first line that
starts ringing, and rings the line until it answers, or the caller hangs up, or the
line's ringer times out.
: The maximum duration of the hunt, either in seconds or cycles. When
this limit is reached, the call is rejected or is forwarded to the specified call
forward number (see below).
-If is greater than , it represents the total time in seconds
to hunt.
-If is less than , it represents the maximum number of
times to cycle through the hunt group. If max is 0, hunting continues
indefinitely until the caller either hangs up or the call is answered.
Exceptions: This value is ignored if , or (but
it must be present and should be set to 1).
4
If the call is unanswered and the maximum hunting duration
has been met, the call is forwarded to the specified number. When forwarding
the call, the SPA8000 sends a 302 response to the ITSP.
NOTE The call forward settings for the individual lines are ignored during hunting. Instead,
the cfwd settings in the Contact List are used.
EXAMPLES:
Lines 1 through 8 are included (). The hunt starts at the
beginning of the list (). When an available line is found, the call stays
with the line until the call is either answered, rejected, or cancelled by the caller
( is entered for ).
A wildcard character ( ) is used to represent all trunk lines. All lines ring
simultaneously (). If there is no answer after 30 seconds (), the call
is forwarded to the specified number (.
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A wildcard character is used to represent all trunk lines. The Trunk UA
chooses lines in random order (). If a selected line does not answer
within 12 seconds (), the Trunk UA chooses another line at random. If there is
no answer after 1 cycle ( ), the call is forwarded to forwarded to the specified
number ().
A wildcard character is used to represent all trunk lines. The Trunk UA
chooses lines in random order (). The interval is *, meaning the hunt
stops when a selected line starts ringing, and will ring the line until it answers,
or the caller hangs up, or the line's ringer times out. If the ringer times out, the
call is automatically forwarded to the specified number ().
Outgoing Call Routing for a Trunk Group
Outbound calls on a trunk line are handled as follows:
4
STEP 1 When a PBX phone selects an outside line, the PBX looks for an open line. If the
PBX finds an open line, it takes the line off hook and bridges the audio between
the PBX phone and the line. On detecting the off hook signal, the SPA8000 Line UA
plays dial tone and ready to collect digits from the PBX phone.
STEP 2 As the PBX phone user dials the number, the Line UA applies its dial plan to the
number. If the Line UA detects an invalid number, it rejects the all by playing
reorder tone, then howling tone, then silence. If a valid number is received, it sends
a SIP INVITE message to the internal Proxy.
STEP 3 The Proxy routes the call to the trunk group UA for the line, and the trunk group UA
will attempt to place the call to the ITSP if there is available capacity on the trunk. If
there is no call capacity left on the trunk, the internal Proxy will reject the INVITE
from the Line UA, which in turn terminates the call and plays reorder tone out to the
FXS port.
NOTE The SPA8000 will also apply the Trunk Dial Plan on the number before sending out
INVITE to the ITSP. This Trunk Dial Plan typically is redundant since the trunk should
trust the number sent by the Line UA. By default the trunk dial plan allows any nonempty number:
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Configuring a Trunk Group
To configure a hunt group, you must first specify the trunk lines by assigning lines
to trunk groups. Then you enter the account information, specify the call capacity,
and configure the Contact List.
Before you begin this procedure, determine which lines you want to associate with
each trunk group that you are configuring. Refer to the following example:
LineTrunk Group
1, 3, 5T1
4, 6, 8T2
2None
4
STEP 1 Connect to the administration web server, and choose Admin access with
Advanced settings.
STEP 2 Assign each line to a trunk group, as needed:
a. Click Voice tab > L , where represents the number of the line interface.
b. In the Trunk Group field, near the top of the line configuration page, choose a
trunk number or choose none for a standalone line (the default setting).
c. Repeat this step for each line that you want to add to a trunk group.
You can check the status of the trunks by clicking the Trunk Status link, which
appears both at the top right corner of the web page and at the lower left corner.
You also can connect directly to the Trunk Status Page by entering the following
URL: spa8000-ip-addr. This page is available with the User
Login or the Admin Login.
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The Trunk Status page shows all calls that are currently active on each trunk
group.
This page shows a snapshot of the trunk activity. You can refresh the data at any
time by clicking the Refresh button on the web browser toolbar. The page shows
the following information:
4
External: The called number
Station: The SPA8000 line that is in use for this call
Direction: The direction of the call, either Outbound or Inbound
State: The state of the call
Calling: An outbound call was initiated but is not ringing at the other end.
Proceeding: The outbound call is ringing at the other end.
Ringing: An inbound call is ringing.
Connected: The call is connected.
Duration: The duration of the call
In the case of a hung call, you can select the check box for the call and then click
the Delete button to cancel the call.
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Setting the Hunt Policy
You can configure the SPA8000 so that the hunt rule applies to all phone or only to
the phones that are on hook.
STEP 1 Connect to the administration web server, and choose Admin access with
Advanced settings.
STEP 2 Click Voice tab > SIP.
STEP 3 Scroll down to the Trunking Parameters section.
STEP 4 In the Hunt Policy field, choose the desired option:
onhook only: The hunt includes only the phones that are on hook.
any state: The hunt includes all phones regardless of the state.
After you complete the required configuration, the FXS port is ready to stream
audio. The functionality depends on the hook state of the FXS port:
If the FXS port is off hook, an incoming call is answered automatically and
audio is streamed to the calling party.
NOTE Each SAS server can maintain up to five simultaneous calls. If the
If the FXS port is on-hook when the incoming call arrives, a SIP 503 response
code is transmitted to indicate Service Not Available.
If an incoming call is auto-answered, but later the FXS port changes to on-hook,
the call is not terminated but continues to stream silence packets to the caller.
5
second line on the unit is disabled, then the SAS line can maintain up
to 10 simultaneous calls. Further incoming calls receive a busy signal
(SIP 486 Response).
The SAS line can be set up to refresh each streaming audio session
periodically using a SIP re-INVITE message, which detects if the connection to
the caller is down. If the caller does not respond to the refresh message, the
SAS line terminates the call so that the streaming resource can be used for
other callers.
Additional information:
The SAS line does not ring for incoming calls even if the attached equipment is
on-hook.
If no calls are in session, battery is removed from tip-and-ring of the FXS port.
Some audio source devices have an LED to indicate the battery status. This can
be used as a visual indication as to whether audio streaming is in progress.
Call Forwarding, Call Screening, Call Blocking, DND, and Caller-ID Delivery
features are not available on an SAS line.
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Configuring Music on Hold
Configuring a Streaming Audio Server
Configuring the Streaming Audio Server
Use the following procedure to configure an SAS with an external music source.
STEP 1 Connect an RJ-11 adapter between the music source (a CD player or iPod, for
example) and an FXS port.
STEP 2 Start Internet Explorer, connect to the administration web server, and choose
Admin access with Advanced settings.
STEP 3 Configure the FXS port:
a. Click Voice tab > FXS, where N represents the number of the FXS port
where you connected the cable from the external music source.
b. In the Subscriber Infomation section, enter the following settings:
5
Display Name: Enter an extension number of name for the FXS 1 port, such
as Receptionist Area Fax Machine.
User ID: Enter a three- to four-digit extension number that is not is use by
another extension.
c. In the Streaming Audio Server (SAS) section, choose yes from the SAS
Enable drop-down list.
STEP 4 Click .
STEP 5 Configure each phone to use this audio source as the MOH server:
a. Click the PBX Status link to view the list of phones.
b. In the list, find the phone that you want to configure, and then click the hyperlink
in the IP Address column. The Telephone Configuration page appears in a
separate window.
c. Click the Ext 1 tab.
d. Scroll down to the Call Feature Settings section.
e. In the MOH Server field, enter the extension number that you assigned to the
FXS port for the streaming audio server.
f.Click .
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Configuring Music on Hold
Configuring a Streaming Audio Server
g. Close the window for the Telephone Configuration page.
h. Repeat this step to configure each phone, as needed.
Using the IVR with an SAS Line
The IVR can still be used on an SAS line, but the user needs to follow the following
steps:
STEP 1 Power off the ATA device.
STEP 2 Connect a phone to the port and make sure the phone is on-hook.
STEP 3 Power on the ATA device.
5
STEP 4 Pick up handset and press * * * * to invoke IVR in the usual way.
If the ATA device boots and finds that the SAS line is on-hook, it does not remove
battery from the line so that IVR may be used. But if the ATA device boots up and
finds that the SAS line is off-hook, it removes battery from the line because no
audio session is in progress.
-FXO Port: The SPA3102 has 1 FXO port that you can connect to the
PSTN. Configure the FXO settings by using the SPA3102 PSTN Line
page.
The SPA8800 is designed to work with your PBX as a PSTN gateway and a
VoIP gateway. Call control is provided by a standard PBX, an Asteriskbased IP PBX, the SPA9000 Voice System, or an Internet-based call control
system.
-FXS Port: The SPA8800 has 4 FXS ports that you can connect to
standard analog telephones or fax machines. Configure the FXS settings
by using the SPA8800 Phone 1-4 pages.
-FXO Port: The SPA8800 has 4 FXO port sthat you can connect to the
PSTN. Configure the FXO settings by using the SPA8800 Line 1-4 pages.
6
How VoIP-To-PSTN Calls Work
To obtain PSTN services through the SPA3102 or the SPA8800, the VoIP caller
establishes a connection with the PSTN Line by way of a standard SIP INVITE
requestaddressedtothePSTNLine.
In two-stage dialing, the SPA3102 takes the FXO port off-hook but does not
automatically dial any digits after accepting the call. To invoke two-stage dialing,
the VoIP caller should INVITE the PSTN Line without the user-id in the Request-URI
or with a user-id that matches exactly the <n> of the PSTN Line. A different
user-id in the Request-URI is treated as a request for one-stage dialing if onestage dialing is enabled, or dropped by the SPA3102 (as if no user-id is given) if
one-stage dialing is disabled.
HTTP Digest Authentication can be also used for two-stage dialing, as in onestage dialing. If using HTTP Digest Authentication or Authentication is disabled, the
VoIP caller should hear the PSTN dial tone right after the call is answered (by a SIP
200 response).
You also can enable PIN authentication. In this case, the VoIP caller is prompted to
enter a PIN number after the SPA3102 answers the call. The PIN number must end
with a # key. The inter-PIN-digit timeout is 10 seconds (not configurable). Up to
eight VoIP caller PIN numbers can be configured on the SPA3102. A dial plan can
be selected for each PIN number. If the caller enters a wrong PIN or the SPA3102
times out waiting for more PIN digits, the SPA3102 tears down the call
immediately with a BYE request.
6
The call scenarios may involve the following types of callers:
VoIP callerSomeone who calls the ATA device via VoIP to obtain PSTN
service
VoIP userA VoIP caller that has a user account (user-id and password) on the
SPA3102
PSTN callerSomeone who calls the ATA device from the PSTN to obtain VoIP
service
VoIP callers can be authenticated by one of the following methods:
No AuthenticationAll callers are accepted for service.
PINCaller is prompted to enter a PIN right after the call is answered.
HTTP digestSIP INVITE must contain a valid authorization header.
PSTN callers can be authenticated by one of the following methods:
No authenticationAll callers are accepted for service.
PINCaller is prompted to enter a PIN right after the call is answered.
3.ThePSTNcallerentersthetargettelephonenumber.Thecollecteddigitsare
processed by the default dial plan.
On the SPA3102, you can add PIN authentication to the basic flow:
1. When a PSTN call comes in to the ATA device and is unanswered (after a
configurable number of rings), then the ATA device takes the FXO port off hook.
2. The SPA3102 prompts the caller to enter the PIN number followed by the # key.
3. The SPA3102 compares the PIN to the configured PSTN PIN values.
If the PIN matches one of the configured PSTN PIN values, then the
SPA3102 plays dial tone. The caller enters the telephone number and the
collected digits are processed by the dial plan associated with the PIN
number. (These dial plans are configured on the Voice Voice tab > PSTN
Line page, Dial Plans section.)
If the PIN does not match one of the configured PSTN PIN values, then the
ATA device plays the reorder tone and then takes the FXO port on-hook.
pwd: Password used for authentication with the given gateway
nat: Enable or disable NAT mapping when calling the gateway
The following table lists some examples.
ExampleDescription
Dial 9 to start outside dial tone, followed by one or
more digits, and route the call to Gateway 1.
Route 911 and 311 calls to the local PSTN gateway
Dial 8 to start outside dial tone, prepend 1408
followed by seven digits, and route the call to
pstn.cisco.com:5061, with user-id = joe, and pwd =
bell_pwd, and enable NAT mapping
Dial 8 to start outside dial tone, prepend 1408
followed by seven digits, and route the call to
Gateway 2, but use the given port, user-id, and
password, and no pstn.cisco.com:5061, and with
Line 1 can have the call forwarded to the PSTN Line after a few seconds
using the Call-Forward-On-No-Answer feature with gw0 as the forward
destination. Similarly, Line 1 can apply Call-Forward-All, Call-Forward-OnBusy, and Call-Forward-Selective feature, and direct the caller to the PSTNGateway.
Only PIN authentication is allowed when a VoIP caller is forwarded to the
PSTN-gateway from Line 1. If HTTP Authentication is used, the caller is not
authenticated.
When using the Forward-To-GW0 feature, you can forward the caller to a
specific PSTN number, using the syntax <>@gw0 in the
forward destination. When using this with Call-Forward-Selective, you can
develop some interesting applications. For example, you can forward all
callers with 408 area code to 14081234567, or all callers with 800 area
code to 18005558355 (This is the number for Tell Me). When this syntax is
used, authentication is not used and the target PSTN number is
automatically dialed by the ATA device after the caller is forwarded to gw0.
TheSPA3102andtheSPA8800haveconfigurablecallprogresstones.Call
progress tones are generatedlocallyontheATA,soanenduserisadvisedofstatus(suchasringback).Parametersforeachtypeoftone(forinstanceadialtoneplayedbacktoanenduser)mayincludethefollowingspecifications:
The PSTN caller calls the PSTN line connected to the FXO port. Ring-Thru is
disabled. After the call rings for a delay equal to the value in ,
the VoIP gateway answers the call and prompts the PSTN caller to enter a PIN
number (assuming PIN authentication is enabled). After a valid PIN is entered, the
caller is prompted to dial the VoIP number. A dial plan is selected according to the
PIN number entered by the caller. If authentication is disabled, the default PSTN
dial plan is used. Note than the dial plan choice cannot be 0 for a PSTN caller.
NOTE A in terms of Caller ID (ANI) patterns can be configured into the
ATA device to automatically grant access to the PSTN caller without entering the
PIN. In this case, the default PSTN dial plan is also used.
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The same scenario can be implemented using Ring-Thru. When the PSTN line
rings, Line 1 rings also. This feature is called . If Line1 is picked up before
the VoIP gateway auto-answers, it is connected to the PSTN call. Line 1 hears a
call waiting tone if it is already connected to another call.
The number dialed is processed by the dial plan corresponding to the VoIP caller.
If the dial plan choice is 0, no dial plan is needed and the user hears the PSTN dial
tone right after the PIN is entered. If the dial plan choice is not 0, the final number
returned from the dial plan after the complete number is dialed by the caller is
dialed to the PSTN. The caller does not hear the PSTN dial tone (except for a little
leakage before the first digit of the final number is auto-dialed by the ATA device).
If the PSTN Line is busy (off-hook, ringing, or PSTN line not connected) when the
VoIP caller calls, the ATA device replies with 503. If the PIN number is invalid or
entered after the VoIP call leg is connected, the ATA device plays the reorder tone
to the VoIP caller and eventually ends the call when the reorder tone times out.
NOTE If is specified and the VoIP caller ID does not match any of the
given patterns, the ATA device rejects the call with a 403. This rule applies
regardless of the authentication method, even when the source IP address of the
INVITE request is in the .
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Using HTTP Digest Authentication (SPA3102)
The same scenario can be implemented with HTTP digest authentication when
the calling device supports the configuration of a auth-ID and password to access
the ATA device PSTN gateway. When the VoIP caller calls the PSTN Line, the ATA
device challenges the INVITE request with a 401 response. The calling device
should then provide the correct credentials in a subsequent retry of the INVITE,
computed with the auth-ID and password using MD5.
If the credentials are correct, the target number specified in the user-id field of the
INVITE Request-URI is processed by the dial plan corresponding to the VoIP user
(assuming the dial plan choice is not 0). The final number is then auto-dialed by the
ATA device.
If the credentials are incorrect, the ATA device challenges the INVITE again. If the
auth-ID does not exist in the ATA device configuration, the ATA device replies 403
to the INVITE. If the target number is invalid according to the corresponding dial
plan, the ATA device also replies 403 to the INVITE. Again, if the PSTN Line is busy
at the time of the call, the ATA device replies 503.
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Configuring the PSTN (FXO) Gateway on the SPA3102
Call Scenarios
NOTE HTTP Digest Authentication is one way to perform one-stage dialing of a VoIP-To-
PSTN call. The other way is with no authentication require. However, if the target
number is not specified in the Request-URI or the number matches the account
user-id of the PSTN Line, the call reverts to two-stage dialing.
Without Authentication (SPA3102 and SPA8800)
This scenario can also be implemented without authentication, using one-stage or
two-stage dialing, as in the HTTP Authentication case. The default VoIP caller dial
plan is used in this scenario. Authentication is performed when the method is none
or when the source IP address of the inbound INVITE matches one of the
patterns.
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Call Forwarding to PSTN Gateway (SPA3102 and SPA8800)
This section describes a number of scenarios that forward calls to the PSTN
gateway. It includes the following topics:
NOTE If the PSTN Line is busy at the moment of the forward, it does not answer the VoIP
call. The call forward rule is ignored and Line 1 continues to ring.
Forward-All to the PSTN gateway
In this scenario, Line 1 is configured with parameter to the PSTN
gateway.This scenario is the same the previous case, except the FXO picks up the
Line 1 call immediately.
If the PSTN Line is busy at the moment of the call, the PSTN Line does not pick up
the call, the call forward rule is ignored, and Line 1 continues to ring.
Forward to a Particular PSTN Number
6
In this scenario, the forward destination is set to <>. This is
the same as in the previous examples, except that the ATA device automatically
dials the given target number on the PSTN line right after it answers the VoIP call
leg. This is a special case of one-stage dialing where the target number is
specified in the configuration. The caller is not authenticated in this case
regardless of the authentication method. However, the caller is still limited by the
parameter
Forward-On-Busy to PSTN Gateway or Number
This scenario is similar to the previous cases of call forwarding to gw0, but this
applies when Line 1 is active.