METRODATA LTD
WCM1100 / WCM3100 / WCM-Serial / LHM1000 / LVM2000 User Manual
76-02-082 Rev N
58 of 169
5.2.2 VLAN Mode
The WCM units support two modes of operation, C-VLAN and QinQ/S-VLAN. The modes
are explained below:
In C-VLAN mode, frames may be untagged, or tagged with an IEEE 802.1q VLAN tag with
Ethertype 8100. Since this is standard VLAN operation they are defined as Customer or
C-VLANs within the WCM range.
In QinQ/S-VLAN mode, frames may ingress an access port either untagged, or already
tagged with a C-VLAN tag and an S-Tag will be pushed onto the frame when it egresses
from a trunk port. An S-Tag uses a user definable EtherType with default value 9100 on
the LAN and SFP ports, but is fixed at 8100 for the VCG port.
5.2.3 Multiple FID (Forwarding Information Database)
When operating in a VLAN environment, the Multiple FID option determines whether each
MAC address is stored with or without the VID.
Enabled
MAC Address Table Partitioned
Disabled
Single partition Table
Note, that when aggregation end point is selected, the Multiple FID table is disabled since
only a single S-Tag is used so partitioning is not required.
5.2.4 L2CP Peering
The IEEE defined that certain layer 2 control protocols were of single segment
significance, and therefore should not pass through switch ports. As the heart of the WCM
unit is a switch, by default it blocks a range of L2CP protocols and peers with IEEE
802.3ah OAM and RSTP BPDU’s. By disabling L2CP peering, no blocking will occur,
though unpredictable operation of the protocols may occur if the unit is used as a multiport
device.
Enabled
IEEE Bridge Group L2CP blocked, OAM/RSTP peered
Disabled
Transparent to L2CP
