3com WX1200 3CRWX120695A Manuel D’Utilisation

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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