System Administration Guide: IP Services

IPQoS on a Network of Server Farms

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

Figure 33–2 Network of IPQoS-Enabled Server Farms

Topology diagram shows a network with a Diffserv router,
an IPQoS-enabled load balancer, and three 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 user ID and project ID. These selectors are included in the application data.

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