User guide

VLAN VLAN Functional Description
iMG/RG Software Reference Manual (Switching)
2-88
TABLE 2-5 Reserved VID Values
2.4.2 VLAN Functional Description
2.4.2.1 VLAN support on Ethernet interfaces
The Gateway supports up to 16 VLANs (irrespective of whether they are carrying tagged or untagged frames)
from VID=1 up to VID=4094.
If a non-tagged or null-VID tagged packet is received, the ingress port VID is used for look up.
The look up process starts with a VLAN table look up to determine whether the VID is valid.
If the VID is not valid the packet will be dropped and its address will not be learned.
If the VID is valid, FID is retrieved for further look up.
FID + DA is used to determine the destination port. FID + SA is used for learning purposes.
2.4.2.1.1 VLAN definition and port tagging
By default the Gateway starts with only one VLAN defined with name default and VID=1.
All the system ports are members of the default VLAN.
Creating and configuring a new VLAN is a two-step process:
• A VLAN is created by specifying a name for the VLAN and its VID value.
• The ports are added to the VLAN. When a port is added it's necessary to specify the frame format in which
packets associated with that VLAN will be transmitted from that port: untagged or tagged.
Note that a physical port can be a member of one or more VLANs.
VID Value
(Hexadecimal) Meaning/Use
0 The null VLAN ID. Indicates that the tag header contains only user
priority information; no VLAN identifier is present in the frame. This
VID value shall not be configured as a PVID, configured in any Filter-
ing Database entry, or used in any Management operation.
1 The default PVID value used for classifying frames on ingress through
a switch port. The PVID value can be changed by management on a
per-port basis.
FFF Reserved for implementation use. This VID value shall not be config-
ured as a PVID, configured in any Filtering Database entry, used in
any Management operation, or transmitted in a tag header.