User guide

B
LACK
D
IAMOND
U
SER
G
UIDE
4-9
T
YPES OF
VLAN
S
M
IXING
P
ORT
-B
ASED AND
T
AGGED
VLAN
S
You can configure the BlackDiamond using a combination of port-based and tagged
VLANs. A given port can be a member of multiple VLANs, with the stipulation that
only one of its VLANs uses untagged traffic. In other words, a port can simultaneously
be a member of one port-based VLAN and multiple tag-based VLANs.
For the purposes of VLAN classification, packets arriving on a port with an
802.1Q tag containing a VLANid of zero are treated as untagged.
G
ENERIC
VLAN R
EGISTRATION
P
ROTOCOL
The Generic VLAN Registration Protocol (GVRP) allows a LAN device to signal other
neighboring devices that it wishes to receive packets for one or more VLANs. The
GVRP protocol is defined as part of the IEEE 802.1Q Virtual LANs draft standard. The
main purpose of the protocol is to allow switches to automatically discover some of the
VLAN information that would otherwise have to be manually configured in each
switch. GVRP can also be run by network servers. These servers are usually configured
to join several VLANs, and then signal the network switches of the VLANs of which
they want to be part.
Figure 4-6 illustrates a network using GVRP.
Figure 4-6:
Network example using GVRP
BD_006
System A
VLAN Red,
Tag 10
Switch B
GVRP: "Send
me traffic for
VLAN tag 10."
MSM
1234AB5678
G6X
F32T
VLAN Red,
Untagged
VLAN Red,
Untagged
GVRP: "Send
me traffic for
VLAN tag 10."
GVRP: "Send
me traffic for
VLAN tag 10."