| This section details how to configure the ProCurve edge switches, the routers, and the TANDBERG terminals.
4.1 Classify, mark, and prioritize traffic
Begin by classifying and marking the network traffic flows.
Classifying traffic: Traffic can be classified according to:
- Protocol: IP, IPX, ARP,…
- TCP or UDP port
- Source IP address
- VLAN
Marking and prioritizing packets: Once you have chosen the classification, you need to mark the video and voice
packets and assign them priority. You can mark traffic with:
- 802.1p (layer 2 priority)
- DSCP (layer 3 priority)
For example, you could decide to mark with priority 6 all traffic coming from VLAN 10. Or to mark with DSCP value 46
all traffic coming from IP address 10.1.10.10.
You can also classify the traffic by the priority value it has before entering the switch. For example, suppose the
videoconferencing terminal has marked its packets with priority 7. You can take all packets marked with this priority
(that is, use the priority as a classifier) and mark them with a DSCP of 46.
Layer 2: At layer 2, use the Ethernet 802.1p priority, which corresponds to 3 bits located in the 802.1Q header of the VLAN and can take values 0 to 7. By default these values are associated with different queues on the switches:
- Low (1-2)
- Normal (0-3)
- Medium (4-5)
- High (6-7)
Layer 2 priority is specified on the switches. This priority will be maintained from one layer 2 equipment to another
across the LAN or VLAN, but will not be routed. Layer 2 priority is specified with the command-line interface (CLI)
using the either the qos priority command or the qos device-priority command.
For example, to assign a priority to the traffic of VLAN 10:
To assign a priority to the traffic coming from source IP address 10.1.10.10:
Layer 3: At layer 3, use the DSCP (Differentiated Services Code Point) field, 6 bits contained in the IP header, to mark
traffic. This value is maintained even when the packets are routed from one LAN or VLAN to another. Voice and video
traffic are usually allocated the DSCP value 46 (101110), which is associated with a priority value of 7, and sent to the
queue with highest priority (Expedited Forwarding) on switches.
Layer 3 priority is specified using the CLI on routers or layer 3 switches. For example, to assign a DSCP value of 46 to the traffic of VLAN 10:
To assign a DSCP value of 46 to the traffic coming from source IP address 10.1.10.10:
After the packets have been marked, they can be associated with different actions:
- Bandwidth allocation:
- Unlimited: The risk of using unlimited bandwidth allocation is that low-priority flows may be completely blocked.
- Limited: Bandwidth allocation can be based on bandwidth % or on value + burst value.
- Modification of DSCP or priority
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4.2 Configure the edge switches
In the setup shown in Figure 1, on the edge switches (ProCurve Switch 3500yl and ProCurve Switch 2610-PWR), the
packets corresponding to the video flow are marked with DSCP value 46 corresponding to Expedited Forwarding
class. You can configure the switches using commands, as shown below:
- Per-VLAN configuration: For example, here VLAN 40 is dedicated to video:
- Per-source-IP-address configuration: For example, here the source IP address (10.1.10.50) is dedicated to
video:
 
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4.3 Configure the routers
The ProCurve Secure Routers 7102dl and 7203dl can either be configured from the CLI or from their web interfaces.
Using the CLI: To modify the DSCP on a Secure Router using the CLI, create the QoS map entry:
This QoS map sets a DSCP value of 46 for all DSCP packets with a priority of 7, and assigns a bandwidth of 1,500 kbps with a burst value of 512 bytes.
Using the router’s Web interface: To configure a QoS map from the router’s Web interface:
- Connect to the router at http://<router_ip_address>. Use the login and password you entered when first setting up the equipment.
- Go to Router / Bridge and then QoS Maps:
- To add a new QoS map, enter a name for this map and a sequence number between 0 and 65535, then click Add. You see the QoS Map Setup window for this map.
- To add a new QoS map, enter a name for this map and a sequence number between 0 and 65535, then click Add. You see the QoS Map Setup window for this map.
- Next, the new QoS map needs to be assigned to a WAN interface. From the QoS Map page, choose a WAN interface (ppp 2 in this example), and assign the QoS map:
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4.4 Marking priority on the TANDBERG terminals
Endpoints such as the TANDBERG terminals can also mark layer 2 and layer 3 priority. Thus, you can either mark the priority on the endpoint directly, or leave the endpoint traffic at its default and mark it at the switch level.
In this example, the ProCurve switches are used to prioritize traffic. So it is not necessary to modify the priority settings on the Tandberg terminals.
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