ZyXEL VMG4381B10A Users Manual

Figure 58 Network Settings > Home Networking > 5th Ethernet Port

The following table describes the fields in this screen.

Table 37 Network Settings > Home Networking > 5th Ethernet Port

LABEL DESCRIPTION

State Select Enable to use the Ethernet WAN port as a LAN port on the Device. Apply Click Apply to save your changes back to the Device. Cancel Click Cancel to exit this screen without saving.

8.10 The MoCA Screen

The VMG4381-B10A supports MoCA (Multimedia over Coax Alliance), which allows multimedia and home networking over coaxial cable. Data communication and audio/video streaming are allowed at the same time.

Chapter 8 Home Networking

Click Network Settings > Home Networking > MoCA to open this screen.

Figure 59 Network Settings > Home Networking > MoCA

The following table describes the fields in this screen.

Table 38 Network Settings > Home Networking > MoCA

LABEL DESCRIPTION

MoCA Privacy Select the check box to enable MoCA privacy . If this is enabled, all devices

connected via coaxial cable must use the same password. Privacy Password Enter the password for the MoCA connection. Enable Auto Scan Select the check box to enable auto scan for the operating frequency. Last Operating

Frequency Apply Click Apply to save your changes back to the Device. Cancel Click Cancel to exit this screen without saving.

Manually select an operating frequency from the droplist.

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8.11 The LAN VLAN Screen

Click Network Setting > Home Networking > LAN VLAN to open this screen. Use this screen to control the VLAN ID and IEEE 802.1p priority tags of traffic sent out through individual LAN ports.

Figure 60 Network Setting > Home Networking > LAN VLAN

The following table describes the labels in this screen.

Table 39 Network Setting > Home Networking > LAN VLAN

LABEL DESCRIPTION

Lan Port These represent the Device’s LAN ports. Tag Operation Select what you want the Device to do to the IEEE 802.1q VLAN ID and priority tags of

802.1P Mark Use this option to set what to do for the IEEE 802.1p priority tags when you add or remark

VLAN ID If you will add or remark tags for this LAN port’s downstream traffic, specify the VLAN ID

Apply Click Apply to save your changes. Cancel

downstream traffic before sending it out through this LAN port.

• Unchange - Don’t do anything to the traffic’s VLAN ID and priority tags.

• Add - Add VLAN ID and priority tags to untagged traffic.

• Remove - Delete one tag from tagged traffic. If the frame has double tags, this removes the outer tag. This does not affect untagged traffic.

• Remark - Change the value of the outer VLAN ID and priority tags.

the tags for a LAN port’s downstream traffic. Either select Unchange to not modify the traffic’s priority tags or select an priority from 0 to 7 to use. The larger the number, the higher the priority.

(from 0 to 4094) to use here.

Click Cancel to exit this screen without saving.

8.12 TFTP Server Name Screen

Click Network Setting > Home Networking > TFTP Server Name to open this screen. Use this screen to access the TFTP (Trivial File Transfer Protocol) Server using DHCP option 66.

Figure 61 Network Setting > Home Networking > TFTP Server Name

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WAN

LAN

The following table describes the labels in this screen.

Table 40 Network Setting

LABEL DESCRIPTION

TFTP Server Name Type a name for the TFTP Server. This allows you to access the TFTP

Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

> Home Networking > TFTP Server Name

server using DHCP option 66. However, option 66 (open standard) supports only the IP address of the hostname or a single TFTP server.

8.13 Technical Reference

This section provides some technical background information about the topics covered in this chapter.

8.13.1

LANs, WANs and the Device

The actual physical connection determines whether the Device ports are LAN or WAN ports. There are two separate IP networks, one inside the LAN network and the other outside the WAN network as shown next.

Figure 62 LAN and WAN IP Addresses

8.13.2 DHCP Setup

DHCP (Dynamic Host Configuration Protocol, RFC 2131 and RFC 2132) allows individual clients to obtain TCP/IP configuration at start-up from a server. You can configure the Device as a DHCP server or disable it. When configured as a server, the Device provides the TCP/IP configuration for the clients. If you turn DHCP service off, you must have another DHCP server on your LAN, or else the computer must be manually configured.

IP Pool Setup

The Device is pre-configured with a pool of IP addresses for the DHCP clients (DHCP Pool). See the product specifications in the appendices. Do not assign static IP addresses from the DHCP pool to your LAN computers.

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8.13.3 DNS Server Addresses

DNS (Domain Name System) maps a domain name to its corresponding IP address and vice versa. The DNS server is extremely important because without it, you must know the IP address of a computer before you can access it. The DNS server addresses you enter when you set up DHCP are passed to the client machines along with the assigned IP address and subnet mask.

There are two ways that an ISP disseminates the DNS server addresses.

• The ISP tells you the DNS server addresses, usually in the form of an information sheet, when you sign up. If your ISP gives you DNS server addresses, enter them in the DNS Server fields in the DHCP Setup screen.

• Some ISPs choose to disseminate the DNS server addresses using the DNS server extensions of IPCP (IP Control Protocol) after the connection is up. If your ISP did not give you explicit DNS servers, chances are the DNS servers are conveyed through IPCP negotiation. The Device supports the IPCP DNS server extensions through the DNS proxy feature.

Please note that DNS proxy works only when the ISP uses the IPCP DNS server extensions. It does not mean you can leave the DNS servers out of the DHCP setup under all circumstances. If your ISP gives you explicit DNS servers, make sure that you enter their IP addresses in the DHCP Setup screen.

Chapter 8 Home Networking

8.13.4 LAN TCP/IP

The Device has built-in DHCP server capability that assigns IP addresses and DNS servers to systems that support DHCP client capability.

IP Address and Subnet Mask

Similar to the way houses on a street share a common street name, so too do computers on a LAN share one common network number.

Where you obtain your network number depends on your particular situation. If the ISP or your network administrator assigns you a block of registered IP addresses, follow their instructions in selecting the IP addresses and the subnet mask.

If the ISP did not explicitly give you an IP network number, then most likely you have a single user account and the ISP will assign you a dynamic IP address when the connection is established. If this is the case, it is recommended that you select a network number from 192.168.0.0 to

192.168.255.0 and you must enable the Network Address Translation (NAT) feature of the Device.

The Internet Assigned Number Authority (IANA) reserved this block of addresses specifically for private use; please do not use any other number unless you are told otherwise. Let's say you select

192.168.1.0 as the network number; which covers 254 individual addresses, from 192.168.1.1 to

192.168.1.254 (zero and 255 are reserved). In other words, the first three numbers specify the

network number while the last number identifies an individual computer on that network.

Once you have decided on the network number, pick an IP address that is easy to remember, for instance, 192.168.1.1, for your Device, but make sure that no other device on your network is using that IP address.

The subnet mask specifies the network number portion of an IP address. Your Device will compute the subnet mask automatically based on the IP address that you entered. Y ou don't need to change the subnet mask computed by the Device unless you are instructed to do otherwise.

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Private IP Addresses

Every machine on the Internet must have a unique address. If your networks are isolated from the Internet, for example, only between your two branch offices, you can assign any IP addresses to the hosts without problems. However, the Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of IP addresses specifically for private networks:

• 10.0.0.0 — 10.255.255.255

• 172.16.0.0 — 172.31.255.255

• 192.168.0.0 — 192.168.255.255

You can obtain your IP address from the IANA, from an ISP or it can be assigned from a private network. If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you with the Internet addresses for your local networks. On the other hand, if you are part of a much larger organization, you should consult your network administrator for the appropriate IP addresses.

Note: Regardless of your particular situation, do not create an arbitrary IP address;

always follow the guidelines above. For more information on address assignment, please refer to RFC 1597, “Ad dress All ocati on for Private Internets” and RFC 1466, “Guidelines for Management of IP Address Space”.

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9.1 Overview

WAN

LAN

The Device usually uses the default gateway to route outbound traffic from computers on the LAN to the Internet. T o have the Device send data to devices not reachable through the default gateway, use static routes.

For example, the next figure shows a computer (A) connected to the Device’s LAN interface. The Device routes most traffic from A to the Internet through the Device’s default gateway (R1). You create one static route to connect to services offered by your ISP behind router R2. You create another static route to communicate with a separate network behind a router R3 connected to the LAN.

Figure 63 Example of Routing Topology

HAPTER

Routing

9.1.1 What You Can Do in this Chapter

•Use the Static Route screen to view and set up static routes on the Device (Section 9.2 on page

158).

•Use the Policy Forwarding screen to configure policy routing on the Device. (Section 9.3 on

page 159).

•Use the RIP screen to set up RIP settings on the Device. (Section 9.4 on page 161).

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9.2 The Routing Screen

Use this screen to view and configure the static route rules on the Device. Click Network Setting > Routing > Static Route to open the following screen.

Figure 64 Network Setting > Routing > Static Route

The following table describes the labels in this screen.

Table 41 Network Setting > Routing > Static Route

LABEL DESCRIPTION

Add new static route

# This is the index number of the entry. Status This field displays whether the static route is active or not. A yellow bulb signifies that this

Name This is the name that describes or identifies this route. Destination IP This parameter specifies the IP network address of the final destination. Routing is always

Subnet Mask This parameter specifies the IP network subnet mask of the final destination. Gateway This is the IP address of the gateway. The gateway is a router or switch on the same

Interface This is the WAN interface used for this static route. Modify Click the Edit icon to edit the static route on the Device.

Click this to configure a new static route.

route is active. A gray bulb signifies that this route is not active.

based on network number.

network segment as the device's LAN or WAN port. The gateway helps forward packets to their destinations.

Chapter 9 Routing

Click the Delete icon to remove a static route from the Device. A window displays asking you to confirm that you want to delete the rout e.

9.2.1 Add/Edit Static Route

Use this screen to add or edit a static route. Click Add new static route in the Routing screen or the Edit icon next to the static route you want to edit. The screen shown next appears.

Figure 65 Routing: Add/Edit

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The following table describes the labels in this screen.

Table 42 Routing: Add/Edit

LABEL DESCRIPTION

Active This field allows you to activate/deactivate this static route.

Select this to enable the static route. Clear this to disable this static route without having to

delete the entry. Route Name Enter a descriptive name for the static route. IP Type Select whether your IP type is IPv4 or IPv6. Destination IP

Address IP Subnet Mask If you are using IPv4 and need to specify a route to a single host, use a subnet mask of

Use Gateway IP Address

Gateway IP Address

Use Interface Select the WAN interface you want to use for this static route. Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

Enter the IPv4 or IPv6 network address of the final destination.

255.255.255.255 in the subnet mask field to force the network number to be identical to

the host ID. Enter the IP subnet mask here.

The gateway is a router or swi tch on the same network segment as t he device's LAN o r WAN

port. The gateway helps forward packets to their destinations.

If you want to use the gateway IP address, select Enable.

Enter the IP address of the gateway.

9.3 The Policy Forwarding Screen

Traditionally, routing is based on the destination address only and the Device takes the shortest path to forward a packet. Policy forwarding allows the Device to override the default routing behavior and alter the packet forwarding based on the policy defined by the network administrator. Policy-based routing is applied to outgoing packets, prior to the normal routing.

You can use source-based policy forwarding to direct traffic from different users through different connections or distribute traffic among multiple paths for load sharing.

The Policy Forwarding screen let you view and configure routing policies on the Device. Click Network Setting > Routing > Policy Forwarding to open the following screen.

Figure 66 Network Setting > Routing > Policy Forwarding

The following table describes the labels in this screen.

Table 43 Network Setting > Routing >Policy Forwarding

LABEL DESCRIPTION

Add new Policy Forwar d Rule

# This is the index number of the entry.

Click this to create a new policy forwarding rule.

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Table 43 Network Setting > Routing >Policy Forwarding (continued)

LABEL DESCRIPTION

Policy Name This is the name of the rule. Source IP This is the source IP address. Source Subnet

Mask Protocol This is the transport layer protocol. Source Port This is the source port number. WAN This is the WAN interface through which the traffic is routed. Modify Click the Edit icon to edit this policy.

his is the source subnet mask address.

Click the Delete icon to remove a policy from the Device. A window displays asking you to

confirm that you want to delete the policy.

9.3.1 Add/Edit Policy Forwarding

Click Add new Policy Forward Rule in the Policy Forwarding screen or click the Edit icon next to a policy. Use this screen to configure the required information for a policy route.

Figure 67 Policy Forwarding: Add/Edit

The following table describes the labels in this screen.

Table 44 Policy Forwarding: Add/Edit

LABEL DESCRIPTION

Policy Name Enter a descriptive name of up to 8 printable English keyboard characters, not including

spaces. Source IP Enter the source IP address. Source Subnet

Mask Protocol Select the transport layer protocol (TCP or UDP). Source Port Enter the source port number. Source MAC Enter the source MAC address. WAN Select a WAN interface through which the traffic is sent. You must have the WAN

Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

Enter the source subnet mask address.

interface(s) already configured in the Broadband screens.

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9.4 The RIP Screen

Routing Information Protocol (RIP, RFC 1058 and RFC 1389) allows a device to exchange routing information with other routers.

Click Network Setting > Routing > RIP to open the RIP screen.

Figure 68 RIP

The following table describes the labels in this screen.

Table 45 RIP

LABEL DESCRIPTION

Interface This is the name of the interface in which the RIP setting is used. Version The RIP version controls the format and the broadcas ti ng me th od of t he RIP packets that

the Device sends (it recognizes both formats when receiving). RIP version 1 is universally supported but RIP version 2 carries more information. RIP version 1 is probably adequate for most networks, unless you have an unusual network topology.

Operation Select Passive to have the Device update the routing table based on the RIP packets

received from neighbors but not advertise its route information to other routers in this interface.

Select Active to have the Device advertise its route information and also listen for routing

updates from neighboring routers. Enabled Select the check box to activate the settings. Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

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10.1 Overview

Quality of Service (QoS) refers to both a network’s ability to deliver data with minimum delay, and the networking methods used to control the use of bandwidth. Without QoS, all traffic data is equally likely to be dropped when the network is congested. This can cause a reduction in network performance and make the network inadequate for time-critical application such as video-ondemand.

Configure QoS on the Device to group and prioritize application traffic and fine-tune network performance. Setting up QoS involves these steps:

1 Configure classifiers to sort traffic into different flows.

2 Assign priority and define actions to be performed for a classified traffic flow.

HAPTER

Quality of Service (QoS)

The Device assigns each packet a priority and then queues the packet accordingly . P ackets assigned a high priority are processed more quickly than those with low priority if there is congestion, allowing time-sensitive applications to flow more smoothly. Time-sensitive applications include both those that require a low level of latency (delay) and a low level of jitter (variations in delay) such as Voice over IP (VoIP) or Internet gaming, and those for which jitter alone is a problem such as Internet radio or streaming video.

This chapter contains information about configuring QoS and editing classifiers.

10.1.1 What You Can Do in this Chapter

•The General screen lets you enable or disable QoS and set the upstream bandwidth (Section

10.3 on page 165).

•The Queue Setup screen lets you configure QoS queue assignment (Section 10.4 on page 166).

•The Class Setup screen lets you add, edit or delete QoS classifiers (Section 10.5 on page 168).

•The Policer Setup screen lets you add, edit or delete QoS policers (Section 10.5 on page 168).

•The Monitor screen lets you view the Device's QoS-related packet statistics (Section 10.7 on

page 175).

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Traffic

Time

Traffic Rate

Traffic

Time

Traffic Rate

(Before Traffic Shaping)

(After Traffic Shaping)

10.2 What You Need to Know

The following terms and concepts may help as you read through this chapter.

QoS versus Cos

QoS is used to prioritize source-to-destination traffic flows. All packets in the same flow are given the same priority. CoS (class of service) is a way of managing traffic in a network by grouping similar types of traffic together and treating each type as a class. You can use CoS to give different priorities to different packet types.

CoS technologies include IEEE 802.1p layer 2 tagging and DiffServ (Differentiated Services or DS). IEEE 802.1p tagging makes use of three bits in the packet header, while DiffServ is a new protocol and defines a new DS field, which replaces the eight-bit ToS (Type of Service) field in the IP header.

Tagging and Marking

In a QoS class, you can configure whether to add or change the DSCP (DiffServ Code Point) value, IEEE 802.1p priority level and VLAN ID number in a matched packet. When the packet passes through a compatible network, the networking device, such as a backbone switch, can provide specific treatment or service based on the tag or marker.

T raffic Shaping

Bursty traffic may cause network congestion. Traffic shaping regulates packets to be transmitted with a pre-configured data transmission rate using buffers (or queues). Your Device uses the Token Bucket algorithm to allow a certain amount of large bursts while keeping a limit at the aver age rate.

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Traffic

Time

Traffic Rate

Traffic

Time

Traffic Rate

(Before Traffic Policing) (After Traffic Policing)

T raffic Policing

Traffic policing is the limiting of the input or output transmission rate of a class of traffic on the basis of user-defined criteria. Traffic policing methods measure traffic flows against user-defined criteria and identify it as either conforming, exceeding or violating the criteria.

The Device supports three incoming traffic metering algorithms: Token Bucket Filter (TBF), Single Rate Two Color Maker (srTCM), and Two Rate Two Color Marker (trTCM). You can specify actions which are performed on the colored packets. See Section 10.8 on page 176 for more information on each metering algorithm.

10.3 The Quality of Service General Screen

Click Network Setting > QoS > General to open the screen as shown next.

Use this screen to enable or disable QoS and set the upstream bandwidth. See Section 10.1 on

page 163 for more information.

Figure 69 Network Settings > QoS > General

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The following table describes the labels in this screen.

Table 46 Network Setting > QoS > General

LABEL DESCRIPTION

QoS Se lect the Enable check box to turn on QoS to improve your network performance. WAN Managed

Upstream Bandwidth

LAN Managed Downstream Bandwidth

Enter the amount of upstream bandwidth for the WAN interfaces that you want to allocate using QoS.

The recommendation is to set this speed to match the interfaces’ actual transmission speed. For example, set the WAN int erfac es’ s pee d t o 100 000 k bps i f your Internet connection has an upstream transmission speed of 100 Mbps.

You can set this number higher than the interfaces’ actual transmission speed. The Device uses up to 95% of the DSL port’s actual upstream transmission speed even if you set this number higher than the DSL port’s actual transmission speed.

You can also set this number lower than the interfaces’ actual transmission speed. This will cause the Device to not use some of the interfaces’ available bandwidth.

If you leave this field blank, the Device automatically sets this number to be 95% of the WAN interfaces’ actual upstream transmission speed.

Enter the amount of downstream bandwidth for the LAN interfaces (including WLAN) that you want to allocate using QoS.

The recommendation is to set this speed to match the WAN interfaces’ actual transmission speed. For example, set the LAN managed downstream bandwidth to 100000 kbps if you use a 100 Mbps wired Ethernet WAN connection.

You can also set this number lower than the WAN inte rfaces’ actual tr ansmission speed. Thi s will cause the Device to not use some of the interfaces’ available bandwidth.

If you leave this field blank, the Device automatically sets this to the LAN interfaces’ maximum supported connection speed.

Upstream traffic priority Assigned by

Apply Click Apply to save your changes. Cancel Click Cancel to restore your previously saved settings.

Select how the Device assigns priorities to various upstream traffic flows.

• None: Disables auto priority mapping and has the Device put packets into the queues according to your classification rules. Traffic which does not match any of the classification rules is mapped into the default queue with the lowest priority.

• Ethernet Priority: Automatically assign priority based on the IEEE 802.1p priority level.

• IP Precedence: Automatically assign priority based on the first three bits of the TOS field in the IP header.

• Packet Length: Automatically assign priority based on the packet size. Smaller packets get higher priority since control, signaling, VoIP, internet gaming, or other real-time packets are usually small while larger packets are usually best effort data packets like file transfers.

10.4 The Queue Setup Screen

Click Network Setting > QoS > Queue Setup to open the screen as shown next.

Use this screen to configure QoS queue assignment.

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Figure 70 Network Setting > QoS > Queue Setup

The following table describes the labels in this screen.

Table 47 Network Setting > QoS > Queue Setup

LABEL DESCRIPTION

Add new Queue Click this button to create a new queue entry. # This is the index number of the entry. Status This field displays whether the queue is active or not. A yellow bulb signifies that this queue

Name This shows the descriptive name of this queue. Interface This shows the name of the Device’s interface through which traffic in this queue passes. Priority This shows the priority of this queue. Weight This shows the weight of this queue. Buffer

Management

Rate L imit This shows the maximum transmission rate allowed for traffic on this queue. Modify Click the Edit icon to edit the queue.

is active. A gray bulb signifies that this queue is not active.

This shows the queue management algorithm used for this queue. Queue management algorithms determine how the Device should handle packets when it

receives too many (network congestion).

Click the Delete icon to delete an existing queue. Note that subsequent rules move up by one when you take this action.

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10.4.1 Adding a QoS Queue

Click Add new Queue or the edit icon in the Queue Setup screen to configure a queue.

Figure 71 Queue Setup: Add

The following table describes the labels in this screen.

Table 48 Queue Setup: Add

LABEL DESCRIPTION

Active Select to enable or disable this queue. Name Enter the descriptive name of this queue. Interface Select the interface to which this queue is applied.

This field is read-only if you are editing the queue.

Priority Select the priority level (from 1 to 7) of this queue.

The smaller the number, the higher t he priority level. Traffic assigned to higher priority queues gets through faster while traffi c in l ower priority queues is dropped if the network is congested.

Weight Select the weight (from 1 to 8) of this queue.

If two queues have the same priority level, the Device divides the bandwidth across the queues according to their weights. Queues with larger weights get more bandwidth than queues with smaller weights.

Buffer Management

Rate L imit Specify the maximum transmission rate (in Kbps) allowed for traffic on this queue. OK Click OK to save your changes. Cancel Click Cancel to exit this screen without saving.

This field displays Drop Tail (DT). Drop Tail (DT) is a simple queue management algorithm that allows the Device buffer to accept as many packets as it can until it is full. Once the buffer is full, new packets that arrive are dropped until there is space in the buffer again (packets are transmitted out of it).

10.5 The Class Setup Screen

Use this screen to add, edit or delete QoS classifiers. A classifier groups traffic into data flows according to specific criteria such as the source address, destination address, source port number, destination port number or incoming interface. For example, you can configure a classifier to select traffic from the same protocol port (such as Telnet) to form a flow.

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You can give different priorities to traffic that the Device forwards out through the WAN interface. Give high priority to voice and video to make them run more smoothly. Similarly, give low priority to many large file downloads so that they do not reduce the quality of other applications.

Click Network Setting > QoS > Class Setup to open the following screen.

Figure 72 Network Setting > QoS > Class Setup

The following table describes the labels in this screen.

Table 49 Network Setting > QoS > Class Setup

LABEL DESCRIPTION

Add new Classifier Click this to create a new classifier. # This is the index number of the entry. Status This field displays whether the classifier is active or not. A yellow bulb signifies that this

Class Name This is the name of the classifier. Classification

Criteria

DSCP Mark This is the DSCP number added to traffic of this classifier.

802.1P Mark This is the IEEE 802.1p priority level assigned to traffic of this classifier. VLAN ID Tag This is the VLAN ID number assigned to traffic of this classifier. To Queue This is the name of the queue in which traffic of this classifier is put. Modify Click the Edit icon to edit the classifier.

classifier is active. A gray bulb signifies that this classifier is not act ive.

This shows criteria specified in this classifier, for example the interface from which traffic of this class should come and the source MAC address of traffic that matches this classifier.

Click the Delete icon to delete an existing classifier. Note that subsequent rules move up by one when you take this action.

10.5.1 Add/Edit QoS Class

Click Add new Classifier in the Class Setup screen or the Edit icon next to a classifier to open the following screen.

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Figure 73 Class Setup: Add/Edit

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The following table describes the labels in this screen.

Table 50 Class Setup: Add/Edit

LABEL DESCRIPTION

Active Select this to enable this classifier. Class Name Enter a descriptive name of up to 15 printable English keyboard characters, not including

Classification Order

From Interface If you want to classify the traffic by an ingress interface, select an interface from the From

Ether Type Select a predefined application to configure a class for the matched traffic.

Source

Address Select the check box and enter the source IP address in dotted decimal notation. A blank

Subnet Netmask

Port Range If you select TCP or UDP in the IP Protocol field, select the chec k box and enter the port

MAC Select the check box and enter the source MAC address of the packet. MAC Mask Type the mask for the specified MAC address to determine which bits a packet’s MAC

Exclude Select this option to exclude the packets that match the specified criteria from this classifier.

Destination

Address Select the check box and enter the source IP address in dotted decimal notation. A blank

Subnet Netmask

Port Range If you select TCP or UDP in the IP Protocol field, select the chec k box and enter the port

MAC Select the check box and enter the source MAC address of the packet. MAC Mask Type the mask for the specified MAC address to determine which bits a packet’s MAC

spaces. Select an existing number for where you want to put this classifier to move the classifier to

the number you selected after clicking Apply. Select Last to put this rule in the back of the classifier list.

Interface drop-down list box.

If you select IP, you also need to configure source or destination MAC address, IP address, DHCP options, DSCP value or the protocol type.

If you select 802.1Q, you can configure an 802.1p priority level.

source IP address means any source IP address. Enter the source subnet mask.

number(s) of the source.

address should match. Enter “f” for each bit of the specified source MAC address that the traffic’s MAC address

should match. Enter “0” for the bit(s) of the matched tr affi c’s MAC address, which can be of any hexadecimal character(s). For example, if you set the MAC address to 00:13:49:00:00:00 and the mask to ff:ff:ff:00:00:00, a packet with a MAC address of 00:13:49:12:34:56 m atches this criteria.

source IP address means any source IP address. Enter the source subnet mask.

number(s) of the source.

address should match. Enter “f” for each bit of the specified source MAC address that the traffic’s MAC address

Exclude Select this option to exclude the packets that match the specified criteria from this classifier.

Others

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Table 50 Class Setup: Add/Edit (continued)

LABEL DESCRIPTION

Service This field is available only when you select IP in the Ether Type field.

This field simplifies classifier configuration by allowing you to select a predefined application. When you select a predefined application, you do not configure the rest of the filter fields.

IP Protocol This field is available only when you select IP in the Ether Type field.

Select this option and select the protocol (service type) from TCP, UDP, ICMP or IGMP. If you select User defined, enter the protocol (service ty pe) number.

DHCP This field is available only when you select IP in the Ether Type field.

Select this option and select a DHCP option. If you select Vendor Class ID (DHCP Option 60), enter the Vendor Class Identifier

(Option 60) of the matched traffic, such as the type of the hardware or firmware. If you select User Class ID (DHCP Option 77), enter a string that identifies the user’s

category or application type in the matched DHCP packets.

Packet Length

DSCP This field is available on ly when you select IP in the Ether Type field.

802.1P This field is available only when you select 802.1Q in the Ether Type field.

VLAN ID This field is available only when you select 802.1Q in the Ether Type field.

This field is available only when you select IP in the Ether Type field. Select this option and enter the minimum and maximu m packet lengt h (from 46 to 1500) in

the fields provided.

Select this option and specify a DSCP (DiffServ Code Point) number between 0 and 63 in the field provided.

Select this option and select a priority level (between 0 and 7) from the drop-down list box. "0" is the lowest priority level and "7" is the highest.

Select this option and specify a VLAN ID number.

TCP ACK This field is available only when you select IP in the Ether Type field.

If you select this option, the matched TCP packets must contain the ACK (Acknowledge) flag.

Exclude Select this option to exclude the packets that match the specified criteria from this classifier.

DSCP Mark This field is available only when you select IP in the Ether Type field.

If you select Mark, enter a DSCP value with which the Device replaces the DSCP field in the packets.

If you select Unchange, the Device keep the DSCP field in the packets.

802.1P Mark Select a priority level with which the Device replaces the IEEE 802.1p priority field in the packets.

If you select Unchange, the Device keep the 802.1p priority field in the packets.

VLAN ID If you select Remark, enter a VLAN ID number with which the Device replaces the VLAN ID

of the frames. If you select Remove, the Device deletes the VLAN ID of the frames before forwarding

them out. If you select Add, the Device treat all matched traffic untagged and add a second VLAN ID. If you select Unchange, the Device keep the VLAN ID in the packets.

Forwar d to Interface

Select a WAN interface through which traffic of this class wil l be forwarded o ut. If you select Unchange, the Device forward traffic of this class according to the default routing table.

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Table 50 Class Setup: Add/Edit (continued)

LABEL DESCRIPTION

To Queue Index Select a queue that applies to this class.

You should have configured a queue in the Queue Setup screen already.

Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

10.6 The QoS Policer Setup Screen

Use this screen to configure QoS policers that allow you to limit the transmission rate of incoming traffic. Click Network Setting > Qo S > Policer Setup. The screen appears as shown.

Figure 74 Network Setting > QoS > Policer Setup

The following table describes the labels in this screen.

Table 51 Network Setting > QoS > Policer Setup

LABEL DESCRIPTION

Add new Policer Click this to create a new entry. # This is the index number of the entry. Status This field displays whether the policer is active or not. A yellow bulb signifies that this

policer is active. A gray bulb signifies that this policer is not active.

Name This field displays the descriptive name of this policer. Regulated

Classes Meter Type This field displays the type of QoS metering algorithm used in this policer. Rule These are the rates and burst sizes against which the policer checks the traffic of the

Action This shows the how the policer has the Device treat different types of traffic belonging to

Modify Click the Edit icon to edit the policer.

This field displays the name of a QoS classifier

member QoS classes.

the policer’s member QoS classes.

Click the Delete icon to delete an existing policer. Note that subsequent rules move up by one when you take this action.

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10.6.1 Add/Edit a QoS Policer

Click Add new Policer in the Policer Setup screen or the Edit icon next to a policer to show the following screen.

Figure 75 Policer Setup: Add/Edit

The following table describes the labels in this screen.

Table 52 Policer Setup: Add/Edit

LABEL DESCRIPTION

Active Select the check box to activate this policer. Name Enter the descriptive name of this policer. Meter Type This shows the traffic metering algorithm used in this policer.

The Simple Token Bucket algorithm uses tokens in a bucket to control when traffic can be transmitted. Each token represents one byte. The algorithm allows bursts of up to b bytes which is also the bucket size.

The Single Rate Three Color Marker (srTCM) is based on the token bucket filter and identifies packets by comparing them to the Committed Information Rate (CIR), the Committed Burst Size (CBS) and the Excess Burst Size (EBS).

The Two Rate Three Color Marker (trTCM) is based on the token bucket filter and identifies packets by comparing them to the Committed Information Rate (CIR) and the Peak Information Rate (PIR).

Committed Rate

Committed Burst Size

Conforming Action

NonConforming Action

Specify the committed rate. When the incoming traffic rate of the member QoS classes is less than the committed rate, the device applies the conforming action to the traffic.

Specify the committed burst size for packet bursts. This must be equal to or less than the peak burst size (two rate three color) or exce ss burst size (single r ate three color) if it is also configured.

This is the maximum size of the (first) token bucket in a traffic metering algorithm. Specify what the Device does for packets within the committed rate and burst size (green-

marked packets).

• Pass: Send the packets without modification.

• DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to

use.

Specify what the Device does for packets that exceed the excess burst size or peak rate and burst size (red-marked packets).

• Drop: Discard the packets.

• DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to

use. The packets may be dropped if there is congestion on the network.

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Table 52 Policer Setup: Add/Edit

LABEL DESCRIPTION

Available Class

Select a QoS classifier to apply this QoS policer to traffic that matches the QoS classifier.

Selected Class

Apply Click Apply to save your changes. Cancel Click Cancel to exit this screen without saving.

Highlight a QoS classifier in the Available Class box and use the > button to move it to the Selected Class box.

To remove a QoS classifier from the Selected Class box, select it and use the < button.

10.7 The QoS Monitor Screen

To view the Device’s QoS packet statistics, click Network Setting > QoS > Monitor. The screen appears as shown.

Figure 76 Network Setting > QoS > Monitor

The following table describes the labels in this screen.

Table 53 Network Setting > QoS > Monitor

LABEL DESCRIPTION

Refresh Interval Enter how often you want the Device to update t his screen. Se lect No Refresh

to stop refreshing statistics. Interface Monitor # This is th e index number of the entry. Name This shows the name of the interface on the Device. Pass Rate This shows how many packets forwarded to this interface are transmitted

successfully. Drop Rate This shows how many packets forwarded to this interface are dropped. Queue Monitor # This is th e index number of the entry. Name This shows the name of the queue. Pass Rate This shows how many packets assigned to this queue are transmitted

successfully. Drop Rate This shows how many packets assigned to this qu eue are dropped.

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10.8 Technical Reference

The following section contains additional technical information about the Device features described in this chapter.

IEEE 802.1Q Tag

The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user priority. The VLAN ID associates a frame with a specific VLAN and provides the information that devices need to process the frame across the network.

IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The following table describes the traffic types defined in the IEEE 802.1d standard (which incorporates the 802.1p).

Table 54 IEEE 802.1p Priority Level and Traffic Type

PRIORITY LEVEL

Level 7 Typically used for network control traffic such as router configuration messages. Level 6 Typically used for voice traffic that is especially sensitive to jitter (jitter is the

Level 5 Typically used for video that consumes high ban dwidth and is sensitive to jitter. Level 4 Typically used for controlled load, latency-sensitive traffic such as SNA (Systems

Level 3 Typically used for “excellent effort” or better than best effort and would include

Level 2 This is for “spare bandwidth”. Level 1 This is typically used for non-critical “background” traffic such as bulk transfers that

Level 0 Typically used for best-effort traffic.

TRAFFIC TYPE

variations in delay).

Network Architecture) transactions.

important business traffic that can tolerate some delay.

are allowed but that should not affect other applications and users.

DiffServ

QoS is used to prioritize source-to-destination traffic flows. All packets in the flow are given the same priority. You can use CoS (class of service) to give different priorities to different packet types.

DiffServ (Differentiated Services) is a class of service (CoS) model that marks packets so that they receive specific per-hop treatment at DiffServ-compliant network devices along the route based on the application types and traffic flow. Packets are marked with DiffServ Code Points (DSCPs) indicating the level of service desired. This allows the intermediary DiffServ-compliant network devices to handle the packets differently depending on the code points without the need to negotiate paths or remember state information for every flow. In addition, applications do not have to request a particular service or give advanced notice of where the traffic is going.

DSCP and Per-Hop Behavior

DiffServ defines a new Differentiated Services (DS) field to replace the Type of Service (TOS) field in the IP header. The DS field contains a 2-bit unused field and a 6-bit DSCP field which can define up to 64 service levels. The following figure illustrates the DS field.

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DSCP is backward compatible with the three precedence bits in the ToS octet so that non-DiffServ compliant, ToS-enabled network device will not conflict with the DSCP mapping.

DSCP (6 bits) Unused (2 bits)

The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each packet gets across the DiffServ network. Based on the marking rule, different kinds of traffic can be marked for different kinds of forwarding. Resources can then be allocated according to the DSCP values and the configured policies.

IP Precedence

Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a layer-3 network. IP precedence uses three bits of the eight-bit ToS (Type of Service) field in the IP header. There are eight classes of services (ranging from zero to seven) in IP precedence. Zero is the lowest priority level and seven is the highest.

Automatic Priority Queue Assignment

If you enable QoS on the Device, the Device can automatically base on the IEEE 802.1p priority level, IP precedence and/or packet length to assign priority to traffic which does not match a class.

The following table shows you the internal layer-2 and layer-3 QoS mapping on the Device. On the Device, traffic assigned to higher priority queues gets through faster while traffic in lower index queues is dropped if the network is congested.

Table 55 Internal Layer2 and Layer3 QoS Mapping

LAYER 2 LAYER 3

PRIORITY QUEUE

IEEE 802.1P USER PRIORITY (ETHERNET

TO S (IP PRECEDENCE)

DSCP

IP PACKET LENGTH (BYTE)

PRIORITY)

0 1 0 000000 12 2 0 0 000000 >1100 3 3 1 001110

001100 001010 001000

4 4 2 010110

010100 010010 010000

5 5 3 011110

250~1100

<250 011100 011010 011000

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Table 55 Internal Layer2 and Layer3 QoS Mapping

LAYER 2 LAYER 3

PRIORITY QUEUE

6 6 4 100110

7 7 6 110000

IEEE 802.1P USER PRIORITY (ETHERNET PRIORITY)

TO S (IP PRECEDENCE)

5 101110

DSCP

100100 100010 100000

101000

111000

IP PACKET

LENGTH (BYTE)

Token Bucket

The token bucket algorithm uses tokens in a bucket to control when tr affic can be transmitted. The bucket stores tokens, each of which represents one byte. The algorithm allows bursts of up to b bytes which is also the bucket size, so the bucket can hold up to b tokens. Tokens are generated and added into the bucket at a constant rate. The following shows how tokens work with packets:

• A packet can be transmitted if the number of tokens in the bucket is equal to or greater than the size of the packet (in bytes).

• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from the bucket.

• If there are no tokens in the bucket, the Device stops transmitting until enough tokens are generated.

• If not enough tokens are available, the Device treats the packet in either one of the following ways:

In traffic shaping:

• Holds it in the queue until enough tokens are available in the bucket.

In traffic policing:

•Drops it.

• T r ansmits it but adds a DSCP mark. The Device may drop these marked pack ets if the network is overloaded.

Configure the bucket size to be equal to or less than the amount of the bandwidth that the interface can support. It does not help if you set it to a bucket size over the interface’s capability . The smaller the bucket size, the lower the data transmission rate and that may cause outgoing packets to be dropped. A larger transmission rate requires a big bucket size. For example, use a bucket size of 10 kbytes to get the transmission rate up to 10 Mbps.

Single Rate Three Color Marker

The Single Rate Three Color Marker (srTCM, defined in RFC 2697) is a type of traffic policing that identifies packets by comparing them to one user-defined rate, the Committed Information Rate (CIR), and two burst sizes: the Committed Burst Size (CBS) and Excess Burst Size (EBS).

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The srTCM evaluates incoming packets and marks them with one of three colors which refer to packet loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and low is referred to as green.

The srTCM is based on the token bucket filter and has two token buckets (CBS and EBS). Tokens are generated and added into the bucket at a constant rate, called Committed Information Rate (CIR). When the first bucket (CBS) is full, new tokens overflow into the second bucket (EBS).

All packets are evaluated against the CBS. If a packet does not exceed the CBS it is marked green. Otherwise it is evaluated against the EBS. If it is below the EBS then it is marked yellow. If it exceeds the EBS then it is marked red.

The following shows how tokens work with incoming packets in srTCM:

• A packet arrives. The packet is marked green and can be transmitted if the number of tokens in the CBS bucket is equal to or greater than the size of the packet (in bytes).

• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from the CBS bucket.

• If there are not enough tokens in the CBS bucket, the Device checks the EBS bucket. The packet is marked yellow if there are sufficient tokens in the EBS bucket. Otherwise, the packet is marked red. No tokens are removed if the packet is dropped.

Two Rate Three Color Marker

The Two Rate Three Color Marker (trTCM, defined in RFC 2698) is a type of traffic policing that identifies packets by comparing them to two user-defined rates: the Committed Information Rate (CIR) and the Peak Information Rate (PIR). The CIR specifies the aver age rate at which packets are admitted to the network. The PIR is greater than or equal to the CIR. CIR and PIR values are based on the guaranteed and maximum bandwidth respectively as negotiated between a service provider and client.

The trTCM evaluates incoming packets and marks them with one of three colors which refer to packet loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and low is referred to as green.

The trTCM is based on the token bucket filter and has two token buckets (Committed Burst Size (CBS) and Peak Burst Size (PBS)). Tokens are generated and added into the two buckets at the CIR and PIR respectively.

All packets are evaluated against the PIR. If a packet exceeds the PIR it is marked red. Otherwise it is evaluated against the CIR. If it exceeds the CIR then it is marked yellow. Finally, if it is below the CIR then it is marked green.

The following shows how tokens work with incoming packets in trTCM:

• A packet arrives. If the number of tokens in the PBS bucket is less than the size of the packet (in bytes), the packet is marked red and may be dropped regardless of the CBS bucket. No tokens are removed if the packet is dropped.

• If the PBS bucket has enough tokens, the Device checks the CBS bucket. The packet is marked green and can be transmitted if the number of tokens in the CBS bucket is equal to or greater than the size of the packet (in bytes). Otherwise, the packet is marked yellow.

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