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New Member

Bandwidth Sharing on WAN Link

We are going to take take one 5 MB dedicated link between 2 offices .

We want to extend following 3 networks

Bridging is he easiest way to do this .

But on single 5 MB link how can we share 3 networks ?

Pls advise .

New Member

Re: Bandwidth Sharing on WAN Link

You could run Frame relay back to back over the link and break it down into seperate PVC's ?

I've done that recently, then used CRB to bridge the PVC's onto Ethernet subinterfaces.

Hope that helps


New Member

Re: Bandwidth Sharing on WAN Link

Hi John ,

Thanks a lot for your reply .

I will go into more details of the setup -

I have 2 cisco 2500 series routers with one Serial and one lan port .

I am going to use Serial link ( Synchronus 5 MB )

Frame Relay will be run as you suggested and will break down into separate PVCs .

But at ethernet end how can I terminate following 3 networks -

And what do you mean by CRB ?




New Member

Re: Bandwidth Sharing on WAN Link

Mmm, 2500's may well give you an issue (no 100Mbps for ISL).

The way I did this was to create on the router's Ethernet port sub interfaces (one per Vlan using ISL) this was connected to a trunk port on a seperate CAT switch where the VLAN's were seperated out. The routers serial interface was configured with frame relay PVC's which were bridged onto the Ethernet's subinterfaces (one per network / PVC).

This allowed me to bridge the Layer 2 networks accros the WAN and extend them to different sites.

I wouldn't recommend this normaly but it helped me get over a migration from ATM LANE issue!

Hope that helps


New Member

Re: Bandwidth Sharing on WAN Link

What media are you going to use for the dedicated link? This will infuence the protocol you will need to use for extending the lans. One option would be to use nat on bothends of the dedicated link. in effect giving you 2 networks for each one you have now but in the same network addressing range. if you added static conversions for the services that needed to be accesed by both networks it would be transparent to the hosts at each site.