Implementing Cisco Networking Solutions

Optimizing the WAN

A WAN link is a critical part of the network, as this is the network segment that is most prone to failures, adds the maximum amount of latency in communications, and is bandwidth constrained. WAN links are generally the choke points on the network from an end-to-end bandwidth perspective. WAN bandwidth is expensive, and hence organizations tend to optimize the WAN utilization.

Most of the communication on the WAN link is TCP/IP. TCP uses a flow control mechanism that restricts the rate at which users can send data on the network. Any loss of packets on the link leads to retransmission of TCP segments, therefore wasting bandwidth. The loss of packets is sensed by the receiving host when the acknowledgment for a given segment ...