FCM9002 USER MANUAL
76-02-095 Rev.B
Page 110 of 145
4.5.2.1 VLAN Mode – STag
In S-Tag mode a service VLAN Tag is pushed onto the user packets and ingress
and removed/popped on egress. The S-Tag has the Ethertype as defined in the
WAN port setup traffic management menu, (4.4.3.9Tagging and Priority). By
default this is set to 9100.
In S-Tag mode, packets ingressing user ports may be untagged, or tagged with
normal or alternative Service VLAN Tags giving rise to packets with multiple tags
as shown below:
Where:
DA
Destination Address
SA
Source Address
ET
EtherType
FCS Frame Check Sequence
CT
IEEE 802.1q VLAN Tag, Etype 8100
ST
Service VLAN Tag, default Etype 9100
In S-Tag mode, each port can support the full range of available C-Tags (1-4095)
with the ability to allocate S-Tags based on the incoming C-Tag, or range of C-
Tags.
