Wide Area Networking Redesign

[Kevin Melton]

I have been tasked with the redesign of a Wide Area Network for my customer.

The current network is configured as follows: 3 Main hub locations 7206 VXR routers that are all connected to each other via Frame Relay T1. This is the main Network Backbone. The network then fans out to six regions, once again connected via frame. Each region has one 256/512 Frame back to its primary Hub location, and another 256/512 location back to its secondary hub location.

Then come the Field Offices. There are 55 field offices throughout the organization. Each of these are 128/256 Frames which also come back to one of the 3 main hub locations...

Some applications are having latency issues at these field offices. I can run a bandwidth monitor and watch these small pipes fill up whenever a transaction is submitted.

I want to improve upon the current design of this network.

Is Frame the best way for this company to be interconnected?.. What is the newest WAN topology out there?? Is ATM an option here??

Please help...

[smif101]

There isn't much that you can do here but upgrade your bandwidth. Frame relay sounds like it is just fine for what you are doing but you will have problems even if you went with ATM at 128k for the link. Your best bet is to prove to management that when users start using applications that go back toward the hub locations and it requires them to download this much data, like a 5MB file. That is 40,000,000 bits and for a remote site to download that much information over a 128k link will take at least 312 secods. You see where this is going. Talk to your local ISP's to see what they can do for you.

[Kevin Melton]

thanks for your valuable input...

[jsayer]

For most organizations, layer 2 frame relay is still a solid option due to pricing and bandwidth flexibilities. Many of the major carriers are now offering layer 3 network services with various service names. Check with your frame relay provider for their offering. AT&T calls their service IP-Enabled Frame-Relay and uses frame as the link type from each of your sites. Essentially each site links into the IPFR network with a single connection and AT&T provides layer 3 service to deliver the traffic directly to the destination. Depending on the vendor, varying levels of QoS can be utilized to protect voice, video and prioritized applications.

If your applications are suffering either from delay issues due to multi-hop frame-relay or bandwidth congestion due to aggregation, this might be worth looking into. This does tend to break the multi-tiered network design, although you could think of the IP-Enabled FR network as the core and all other sites as dist or access nodes.

Hope this helps,

John