Gvrp; Tagged Frames Forwarding Example; Untagged Frames Forwarding Example - ZyXEL Communications MSC1024G Series User Manual

17.3.2 GVRP

GVRP (GARP VLAN Registration Protocol) is a registration protocol that defines a way for
switches to register necessary VLAN members on ports across the network. Enable this
function to permit VLANs groups beyond the local switch.
Please refer to the following table for common IEEE 802.1Q VLAN terminology.
Table 282 IEEE 802.1Q VLAN Terminology
VLAN PARAMETER TERM
VLAN Type
VLAN Administrative
Control
VLAN Tag Control
VLAN Port

17.4 Tagged Frames Forwarding Example

1 First the MSC checks the VLAN ID (VID) of tagged frames or assigns temporary VIDs
to untagged frames.
2 The MSC then checks the VID in a frame's tag against the SVLAN table.
3 The MSC notes what the SVLAN table says (that is, the SVLAN tells the MSC whether
or not to forward a frame and if the forwarded frames should have a tag).
4 Then the MSC applies the port filter to finish the forwarding decision. This means that
frames may be dropped even if the SVLAN says to forward them. Frames might also be
dropped if they are sent to a CPE (customer premises equipment) DSL device that does
not accept tagged frames.

17.5 Untagged Frames Forwarding Example

1 An untagged frame comes in from the LAN.
2 The MSC checks the PVID table and assigns a temporary VID.
MSC1000G/1024G/1224G Series User's Guide
DESCRIPTION
Permanent VLAN This is a static VLAN created manually.
Dynamic VLAN This is a VLAN configured by a GVRP registration/
deregistration process.
Registration Fixed Fixed registration ports are permanent VLAN members.
Registration Ports with registration forbidden are forbidden to join the
Forbidden specified VLAN.
Normal Registration Ports dynamically join a VLAN using GVRP.
Tagged Ports belonging to the specified VLAN tag all outgoing
frames transmitted.
Untagged Ports belonging to the specified don't tag all outgoing
frames transmitted.
Port VID This is the VLAN ID assigned to untagged frames that
this port received.
Acceptable Frame You may choose to accept both tagged and untagged
Type incoming frames or just tagged incoming frames on a
port.
Ingress Filtering If set, the switch discards incoming frames for VLANs
that do not have this port as a member
Chapter 17 VLAN Screens
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