IPQoS on a Network of Server Farms

The following figure shows a network with several heterogeneous server farms.

In such a topology, the router is diffserv-aware, and therefore able to queue and rate both incoming and outgoing traffic. The load balancer is also diffserv-aware, and the server farms are IPQoS-enabled. The load balancer can provide additional filtering beyond the router by using selectors such as userID and projectID, which are included in the application data.

Figure 2–2 Network of IPQoS-Enabled Server Farms

This scenario provides flow control and traffic forwarding to manage congestion on the local network. The topology also prevents outgoing traffic from the server farms from overloading other portions of the intranet.