Chapter 9 VLAN
GS2200 Series User’s Guide
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level is significant and the default VID of the ingress port is given as the VID of the frame. Of the
4096 possible VIDs, a VID of 0 is used to identify priority frames and value 4095 (FFF) is reserved,
so the maximum possible VLAN configurations are 4,094.
Forwarding Tagged and Untagged Frames
Each port on the Switch is capable of passing tagged or untagged frames. To forward a frame from
an 802.1Q VLAN-aware switch to an 802.1Q VLAN-unaware switch, the Switch first decides where
to forward the frame and then strips off the VLAN tag. To forward a frame from an 802.1Q VLAN-
unaware switch to an 802.1Q VLAN-aware switch, the Switch first decides where to forward the
frame, and then inserts a VLAN tag reflecting the ingress port's default VID. The default PVID is
VLAN 1 for all ports, but this can be changed.
A broadcast frame (or a multicast frame for a multicast group that is known by the system) is
duplicated only on ports that are members of the VID (except the ingress port itself), thus confining
the broadcast to a specific domain.
9.1.2.1 Automatic VLAN Registration
GARP and GVRP are the protocols used to automatically register VLAN membership across switches.
GARP
GARP (Generic Attribute Registration Protocol) allows network switches to register and de-register
attribute values with other GARP participants within a bridged LAN. GARP is a protocol that provides
a generic mechanism for protocols that serve a more specific application, for example, GVRP
.
GARP Timers
Switches join VLANs by making a declaration. A declaration is made by issuing a Join message
using GARP. Declarations are withdrawn by issuing a Leave message. A Leave All message
terminates all registrations. GARP timers set declaration timeout values.
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 VLAN
groups beyond the local Switch.
Please refer to the following table for common IEEE 802.1Q VLAN terminology.
TPID
2 Bytes
User Priority
3 Bits
CFI
1 Bit
VLAN ID
12 bits
Table 16
IEEE 802.1Q VLAN Terminology
VLAN PARAMETER
TERM
DESCRIPTION
VLAN Type
Permanent VLAN
This is a static VLAN created manually.
Dynamic VLAN
This is a VLAN configured by a GVRP registration/
deregistration process.
Summary of Contents for GS2200 Series
Page 15: ...15 PART I User s Guide...
Page 16: ...16...
Page 31: ...31 PART II Technical Reference...
Page 32: ...32...
Page 76: ...Chapter 8 Basic Setting GS2200 Series User s Guide 76...
Page 92: ...Chapter 9 VLAN GS2200 Series User s Guide 92 Figure 60 Port Based VLAN Setup Port Isolation...
Page 230: ...Chapter 29 Error Disable GS2200 Series User s Guide 230...
Page 248: ...Chapter 33 ARP Learning GS2200 Series User s Guide 248...
Page 302: ...Appendix A Changing a Fuse GS2200 Series User s Guide 302...
Page 306: ...Appendix B Common Services GS2200 Series User s Guide 306...
Page 309: ...Appendix C Legal Information GS2200 Series User s Guide 309 ROHS...
Page 310: ...Appendix C Legal Information GS2200 Series User s Guide 310...