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New Member

Trunk across T1/router

I have a layer 2 network setup that use fiber GBICs to interconnect and use many VLANs. I have a remote site that I need to setup and I can only get a T1 connection. So my question is..... Is there a way to trunk over a T1 using a router(2600). The reason I am using the router is for media conversion.


Re: Trunk across T1/router

This link shows some samples of the newer way to do this. You can of course build subinterfaces and bridge them.

Still just because you can do this it is not the best thing to do. You need to minimize the number of vlans that cross the t1 and try to limit the broadcast traffic if you can.

A LAN is very tolerate of broadcast traffic since there is so much bandwidth. The WAN connection is much less bandwidth and can cause issues becuase of the latency due to distance.

I would recommend you plan to eventually change your design to route between the remote location rather then bridge. There are very few application anymore that require layer 2 connection. It may be a big chore to redo addresses and such but it is much easier than troubleshooting a bridged WAN link,

New Member

Re: Trunk across T1/router

I agree with you completely but the issue that I have is that we have 30 locations that need 10 seperate LANs to be isolated. If I use routing I would have to put thousands of ACLs. So it is much easier to use the VLans in my setup because I user fiber trunks between the locations excrpt for this one.

New Member

Re: Trunk across T1/router

Unless you know of a way for me to route across multiple vlans without allowing them to communicate.


Re: Trunk across T1/router

Talk to your carrier / provider to get MPLS.

As implemented by most carriers, MPLS uses VPNs @ layer three and tags accordng to the IP address provided to the carrier's PE (Provider Edge).

Check it out


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