Examples of QoS implementation
Issue 3.4.1 June 2005
329
Figure 85: High-quality service across a congested WAN link
CB-WFQ/LLQ is a priority-aware queuing strategy that has a strict priority queue for voice
packets, and does round-robin queuing for other types of traffic. Non-prioritized traffic is still
forwarded, however, so this should not interfere with a customer’s data network. Use weighted
random early detect to manage the fair queue.
The actual router configuration used for this testing follows. First, set the endpoints to tag
interesting traffic as DSCP 46. Cisco routers support DiffServ in IOS 12.0 and later. Next, set up
a class map to match traffic that is marked with DSCP 46. Once traffic is defined by the class
map, set policies for it using a policy map. For the policy map to take effect, it has to be applied
to an interface. Queue packets on the outgoing interface. In the sample configuration, 768 K of
bandwidth is reserved for RTP. This value should be set at or above the maximum bandwidth to
be used for IP Telephony. In our case, 768 K supports 9 calls using G.711, or 31 calls using
G.729. This example should work well in most cases using Cisco routers with point-to-point
WAN links. Networks that use Frame Relay might need additional steps.
Assumptions for Example 1
Suppose all endpoints are capable of tagging with DSCP 46, which is the default for audio. This
would be true in a Communication Manager system with TN799DP C-LAN circuit packs running
firmware v5 or later. Previous firmware versions and the TN799C circuit pack cannot tag at
Layer 2 or Layer 3. A matching set of configurations is applied to both routers.
Содержание Application Solutions
Страница 1: ...Avaya Application Solutions IP Telephony Deployment Guide 555 245 600 Issue 3 4 1 June 2005 ...
Страница 20: ...About This Book 20 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 21: ...Issue 3 4 1 June 2005 21 Section 1 Avaya Application Solutions product guide ...
Страница 22: ...22 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 74: ...Avaya Application Solutions platforms 74 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 106: ...Call processing 106 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 124: ...Avaya LAN switching products 124 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 139: ...Issue 3 4 1 June 2005 139 Section 2 Deploying IP Telephony ...
Страница 140: ...140 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 186: ...Traffic engineering 186 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 204: ...Security 204 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 214: ...Voice quality network requirements 214 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 228: ...Avaya Integrated Management 228 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 239: ...Reliability Issue 3 4 1 June 2005 239 Figure 69 S8700 Media Server in a high reliability configuration ...
Страница 274: ...Reliability and Recovery 274 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 275: ...Issue 3 4 1 June 2005 275 Section 3 Getting the IP network ready for telephony ...
Страница 276: ...276 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 350: ...Implementing Communication Manager on a data network 350 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 356: ...Network recovery 356 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 366: ...Network assessment offer 366 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 367: ...Issue 3 4 1 June 2005 367 Appendixes ...
Страница 368: ...Appendixes 368 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 394: ...Access list 394 Avaya Application Solutions IP Telephony Deployment Guide ...
Страница 414: ...DHCP TFTP 414 Avaya Application Solutions IP Telephony Deployment Guide ...