Design Setup

[kmcelroy]

We are a growing ISP and currently have the following setup:

A 3662 Core Router at our main location. 4 T1's for bandwith coming in, 4 T1 Frame Clouds that go out to our other POP's. From one of the Ethernet ports on the router module we tie in a Catalyst 2900XL which supplies our servers. I was going to purchase an ALLOT NetEnforcer, but with this current design I would have to put a box at every POP!! I spoke with a rep at the company who said that most ISP's have a Edge router where there incoming T's (bandwidth) connect and another router for the Frame Relay circuits coming in from outside POP's He recommended tying the two routers together via a switch?

I had no say so in the current design and it is up to me to make it more efficient? Could someone provide me with some insight on what other people have for setup? Suggestions and/or comments would help. Hardware recommendations considerations?

 

[writemem]

Kmcelroy,
I'm a little unsure as to your question could. What are you trying to do? sorry if i'm missing something obvious.

Mark

 

[kmcelroy]

I was curious if Most ISP's have an Edge Router that there uplinks for bandwidth connected to. Then for the additional pops if they had a 2nd Router for them and connected these two routers via a switch? More on Design Is what I was curious about.

4 T1's from Diff Providers
| | | |
| | | |
Edge Router
|
|
Switch
|
|
Pop Router
| | | |
Different Pops via Frame relay

So is the above how most ISP's tie there stuff together? That is my question?

 

[writemem]

It would seem to me that adding the switch would only add latency. If you had a router capable of many serial interfaces Such as a 7200 series you could connect 4 T-1's to the router and the 4 FR circuits to the same router. what this will do is cut down on the amount of transition points. packets switched from the pop to a bandwidth provider will come in on one interface, go through the routing process then leave on another interface. with the switch setup it comes in on an interface goes through a routing process gets forwarded to the switch on int 0/1 then sent out int 0/2 then into the routing process on the second router then out an interface. Obviously you can see that there is a difference in the way both set-up's perform. If you looking to seperate these for management than that's one thing but I'd try to stick with one router.

Disclaimer: Understand that this is just my opinion without being in your data center it is just that an opinion based on my knowledge of network design.