Field Guide to Wireless LANs for Administrators and Power Users, A

Summary

The topics of medium access, MAC timing, power saving, fragmentation, and retransmission, are all inter-related. This can cause considerable confusion, since it is often difficult to remember which rule trumps another in a given situation. In this chapter, we have seen all the important bits and perhaps also exposed the reader to the complexity, in that the pieces are all inter-dependent and it is often necessary to mention special cases while trying to describe the “main mode” of operation.

DCF is that main mode, and it embodies the CSMA/CA access control protocol and a slew of timing-related rules. PCF is optional, and allows for polling-oriented access managed by an entity in the AP known as the Point Coordinator. PCF is built on DCF, ...