userMango wrote

How to frames work for untagged ports?

If I have a port A which has say VPID 200, has VLAN 200 untagged and also VLAN 150 untagged, does that mean that frames on the switch tagged 150 can reach port A, and open a connection, but port A cannot go find IPs/MACs on VLAN 150? I haven't seen this discussed in detail, but does this create 1 way VLANs in a sense?

 

Hi userMango.

 

We can see a simple example.

 

PC1-------(untagged port, PVID 200, VLAN 100/200) Switch (untagged port, PVID 100, VLAN 100/200)-------PC2

 

Both PCs use untagged packets. These two PCs can access each other. The data going back and forth is different VLAN.

PC1 data is transmitted to PC2 through VLAN 200, because PVID is 200 for the port connected to PC1.

PC2 data is transmitted to PC1 through VLAN 100, because PVID is 100 for the port connected to PC2.

It is so basic thing, so I advise you to read some materials or check some youtube videos by yourself to fully understand, how it works.