Difference between tag and untag in topology creation

[Saiprasad_Rao_R]

What is the Difference between tag and untag in topology creation..... Say suppose 6 topologies ( Bridge @ AP) with different vlans are created on same interface and that interface also has mgmt IP on it and will be the only interface used connected to lan(switch)...... will all 6 topolies be created as tagged or untagged.......

[Gareth_Mitchell]

B@AP means bridge at AP, this is exactly what happens, all the traffic is switched at layer 2 in the defined vlan, user data traffic is not tunnelled back to the controller, traffic egressing the AP will be placed into the defined vlan, after that it's up to the wired network to deliver the traffic to its destination and back (by conventional switch/route) If you define egress traffic as tagged in the AP config, then the AP expects to receive matching traffic tagged.

If you want to tunnel traffic to the controller so that it arrives at a central point, then use a bridge at controller topology (B@AC) - with this topology type, you would need to tag vlan traffic to the controller but not at the AP.

In summary:

B@AP traffic doesn't need to arrive at the controller tagged or untagged but does need to be tagged/untagged at the AP.
B@AC traffic doesn't need to arrive at the AP tagged or untagged, but does need to arrive at the controller tagged/untagged.
Choice of tagged or untagged is up to you. As previously stated only 1 vlan can be untagged.

Also note that you cannot add a L3 entity to a B@AP topology. The l3 entity (if required) must live elsewhere in the wired world, it's external to the controller/AP.

[Saiprasad_Rao_R]

But how will multiple topologies pass on single interface of controller. If u say on core vlans will not be tagged , that means on controller port all topologies should be untagged...... am I right... can you pls explain in detail.... there is lot of confusion....

[Bharathiraja__S]

Hi Sai,

Each topology is identified with the vlan ID and each L2 port can have only one untagged topology.VLAN ID is used as a Controller wide identification of the topologies, however the VLAN ID is only used for tagged topologies.

Thanks,

Suresh.B

[Eric_Jones]

Yes, somewhere on the network there needs to be routes created so that the different vlans can communicate.

[Saiprasad_Rao_R]

OK got it..... Correct me if I am wrong. A separate topology has to be created with IP address with mode as physical and will be untagged on the port. And rest of the L2 topologies (B@AP) will be on the same port as tagged.....and a static route has to be created to the management IP gateway....