BROADCAST/MULTICAST FILTERING BY THE BRIDGE-BASED ACCESS POINT

摘要

In communication systems which include high speed wired local area networks (LAN s) and low speed wireless LANs, the bandwidth of the wireless LANs can be severely impa cted. It has been found that many broadcast or multicast messages which are forwarded to the wireless LANs are not required as the mobile terminals which would receive the m essages are not required to act on them. The present invention provides a means and meth od to filter out unneeded messages so that they do not impact the bandwidth of the wir eless network. Each access point for each wireless LAN maintains a table of parameters for each associated mobile terminal in the connected wireless LAN. The parameters in that table are compared to the parameters in message frames received by the access point an d only those messages having parameters found in the table are put on the wireless LAN. The level of filtering can be controlled by specifying which parameters are to be us ed for filtering messages. The tables at each access point are maintained current by mo ving table entries from access point to access point as mobile terminals move from wireless LAN to wireless LAN and by removing inactive table entries from the table when a predet ermined interval of inactivity is encountered and a terminal is determined to be no long er in active contact with the access point.