When do I need to use TCP/IP header compression instead of Layer 2 payload compression?
A. TCP/IP header compression is designed to be used for slow serial links of 32 k or less, and to produce a significant performance impact. It requires highly interactive traffic with small packet sizes. In such traffic, the ratio of Layer 3 and Layer 4 header to payload is relatively high. Therefore, performance can be improved if you shrink the headers. Layer 2 payload compression applies the selected compression algorithm to the entire frame payload, which includes the TCP/IP headers. It is designed to be used on links that operate at speeds from 56 k to 1.544 M. It is useful on all types of traffic, as long as the traffic has not been previously compressed by a higher-layer application.
