User guide

Canopy System User Guide
pmp-0229 (Mar 2013)
167
Chapter 14: Engineering VLANs
The radios support VLAN functionality as defined in the 802.1Q (Virtual LANs) specification, except
for the following aspects of that specification:
• the following protocols:
o Generic Attribute Registration Protocol (GARP) GARV
o Spanning Tree Protocol (STP)
o Multiple Spanning Tree Protocol (MSTP)
o GARP Multicast Registration Protocol (GMRP)
• priority encoding (802.1P) before Release 7.0
• embedded source routing (ERIF) in the 802.1Q header
• multicast pruning
• flooding unknown unicast frames in the downlink
As an additional exception, the AP does not flood downward the unknown unicast frames to the SM.
A VLAN configuration in Layer 2 establishes a logical group within the network. Each computer in
the VLAN, regardless of initial or eventual physical location, has access to the same data. For the
network operator, this provides flexibility in network segmentation, simpler management, and
enhanced security.
Special Case VLAN Numbers
This system handles special case VLAN numbers according to IEEE specifications:
VLAN
Number
Purpose Usage Constraint
0
These packets have 802.1p priority, but are
otherwise handled as untagged.
Should not be used as
a management VLAN.
1
Although not noted as special case by IEEE
specifications, these packets identify traffic
that was untagged upon ingress into the SM
and should remain untagged upon egress.
This policy is hard-coded in the AP.
Should not be used for
system VLAN traffic.
4095 This VLAN is reserved for internal use.
Should not be used
at all.