Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
New Member

Isolation at layer two of customers on the same VLAN

My ISP customer would like to deploy FTTH solution using rings as showed in the attachement made of ME-3400 or 4500-E depending on how many customer have to be connected to each area (less than 80 --> we go for ME 3400, more than 80 --> we go for 4500-E).


1) each customer will be connecting to the switches through CPE using trunking where will be transported each service (VoIP, Internet access, MPLS layer 3 vpn, CPE mgmt)

2) each one of the previous services has its own FIXED vlan (i mean, the same VLANs are used for all the customers and the ISP customer doesn't like the idea to use different VLANs at least per device...doesn't scale); that means that on each port of the access switches we'll have replicated the same VLAN in trunking depending on services that have been sold to each customer

3) for security reasons, the ISP customer doens't want that each customer can get connected to each other using L2 ring infrastructure as shortcut, so even though in the same VLAN, they have to be ISOLATED among them

Now, the problem is the following one:

Especially regarding the point #3, the logical solution is to use PVLAN with "isolated PVLAN trunk ports" among the switches in order to avoid that customers, not only the ones attached at the same switch, but also on different switches, to communicate each other (configuring the access trunk port as secondary isolated port) ...and that's fine for 4500-E.

...the problem comes up with ME3400 that doesn't support "isolated PVLAN trunk ports"; so locally i can manage the issue thanks to UNI ports definition (that is like to say ISOLATE them) but "no way" if we extend the concept among different switches.

Any idea about that? to solve on 3400 the problem of isolation among customers spread over the different switches of the ring?



CreatePlease to create content