3Com 3CRWX120695A, 3CRWX440095A Configuration Manual page 128

128 C 6: C
HAPTER ONFIGURING
MAP A P
CCESS OINTS
4 Find WX message times out. MAP then sends a DNS request for
3COMWX.example.com.
5 DNS server sends the system IP address of the WX switch mapped to
3COMWX.example.com. In this example, the address is for WX1.
6 MAP sends a unicast Find WX message to WX1.
7 WX1 receives the Find WX message and compares the bias settings on
each WX for the MAP. More than one WX has a high bias for the MAP,
so WX1 selects the WX that has the greatest capacity to add new active
MAP connections. In this example, WX1 has more capacity. WX1 sends
its own IP address in the Find WX Reply message to the MAP.
8 MAP requests a software image and configuration from WX1.
Session Load Balancing
You can assign MAP access points to a load-balancing group. A
load-balancing group helps reduce congestion by distributing client
sessions among the MAP access points in the group. For example, if an
802.11b/g radio operating on channel 1 is supporting more sessions than
a neighboring 802.11b/g radio operating on channel 6, the
load-balancing feature can reject association requests to the radio on
channel 1.
To balance the sessions, MSS rejects an association request for an access
point's radio if that radio has at least four more active sessions than the
radio of the same type with the least number of active sessions within the
group. If the rejected client associates with another access point in the
same group, the session load among the access points in the group
becomes more balanced.
Load balancing is based only on association requests for new sessions.
Adding a MAP access point to a group does not affect sessions that are
already active on the access point. In addition, MSS does not attempt to
rebalance sessions when a client disassociates from an access point. If
MSS rejects an association request for load-balancing reasons but not for
authentication reasons, the rejection does not count as an authentication
failure.
3Com recommends that you configure small groups and ensure that all
the radios in the group provide comparable coverage within the same
service area.