Advanced Traffic Management Guide K/KA/KB.15.15

Example 44 Networked 802.1Q-compliant devices with multiple VLANs on some ports
Network, switches X and Y and servers S1, S2, and the AppleTalk server are 802.1Q-compliant.
(Server S3 could also be 802.1Q-compliant. This network includes both protocol-based (AppleTalk)
VLANs and port-based VLANs.
• The VLANs assigned to ports X4 - X6 and Y2 - Y5 can all be untagged because there is only
one VLAN assigned per port.
• Port X1 has two AppleTalk VLANs assigned, which means that one VLAN assigned to this
port can be untagged and the other must be tagged.
• Ports X2 and Y1 have two port-based VLANs assigned, so one can be untagged and the other
must be tagged on both ports.
• Ports X3 and Y6 have two port-based VLANs and one protocol-based VLAN assigned. Thus,
one port-based VLAN assigned to this port can be untagged and the other must be tagged.
Also, since these two ports share the same link, their VLAN configurations must match.
Switch YSwitch X
Green VLANRed VLANAT-2 VLANAT-1 VLANPortGreen VLANRed VLANAT-2 VLANAT-1 VLANPort
TaggedUntaggedNo
1
No
1
Y1No
1
No
1
TaggedUntaggedX1
UntaggedNo
1
No
1
No
1
Y2TaggedUntaggedNo
1
No
1
X2
No
1
No
1
UntaggedNo
1
Y3TaggedUntaggedUntaggedNo
1
X3
UntaggedNo
1
No
1
No
1
Y4UntaggedNo
1
No
1
No
1
X4
No
1
UntaggedNo
1
No
1
Y5No
1
UntaggedNo
1
No
1
X5
TaggedUntaggedUntaggedNoY6No
1
No
1
No
1
UntaggedX6
1
No means the port is not a member of that VLAN. For example, port X3 is not a member of the Red VLAN and does not carry Red
VLAN traffic. Also, if GVRP were enabled (port-based only), Auto would appear instead of No.
NOTE: VLAN configurations onports connected by the same link must match. Because ports X2
and Y5 are opposite ends of the same point-to-point connection, both ports must have the same
VLAN configuration, configuring the Red VLAN as "Untagged" and the Green VLAN as "Tagged.”
56 Static Virtual LANs