3Com WX2200 3CRWX220095A Switch User Manual


 
252 CHAPTER 10: CONFIGURING MAP ACCESS POINTS
Configuring Local
Packet Switching
on MAPs
MAPs can be configured to perform local packet switching. Local packet
switching
allows packets to be switched directly from the MAP to the
wired network, instead of passing through an intermediate WX
switch. When a MAP is configured to perform local switching, the WX
switch is removed from the forwarding path for client data traffic.
When local switching is enabled, the client VLAN is directly accessible
through the wired interface on the MAP. Packets can be switched directly
to and from this interface.
Normally, when local switching is not enabled on a MAP, packets are
tunneled through the network back to a WX, where the traffic is placed
on the client VLAN. This process requires packets to be encapsulated,
de-encapsulated, and possibly fragmented, which may introduce latency
in the switching path.
Omitting the WX switch from the forwarding path for client traffic
eliminates the tunnel encapsulation process, which can result in improved
network performance.
Local packet switching is disabled by default. A MAP can be configured
to switch packets for some VLANs locally and tunnel packets for other
VLANs through the WX.
Notes:
Restricting Layer 2 forwarding for a VLAN is not supported if the
VLAN is
configured for local switching
The DHCP restrict feature is not supported for locally switched clients
Web Portal is not supported for locally switched clients
A directly attached MaP, for which a port has been specified with the
set port type command, cannot be configured to perform local
switching. However, a directly connected MaP for which a port has
not been specified can perform local switching.
IGMP snooping is not supported with local switching