Cisco T1 Bonding Hardware?

[jeff]

I have a client who has a Tiara Networks 1400 unit which bonds T1 circuits together. I would like to replace this with a Cisco unit. What technology, or hardware does Cisco offer to do this?

Thanks for any help.

Jeff

[Georg Pauwen · Accepted solution]

Hello Jeff,

any Cisco router that has multiple serial interfaces supports what is called a ppp multilink group. Let´s say you have a Cisco 3745 router, or a 2600 router, with four serial interfaces, each connected to a T1. To bond the 4 T1s into one bundle, which effectively gives you a 6MB link, you would add the following to each interface configuration:

interface serial X

encapsulation ppp

ppp multilink group 1

ppp multilink

HTH,

Georg

[jeff]

Thanks for the reply.

Does the other end of the circuits, let's say the ISP side, have to configure PPP on their equipment for this to work?

BTW. Is this MLPP?

Thanks again.

Jeff

[thisisshanky · Accepted solution]

Jeff,

If the T1s are going to an ISP, you will have to ask them to configure their end with Multilink and use PPP encapsulation on their routers. ISPs some times use HDLC as default encapsulation and assign N number of subnets (/30 masks) to you for each of your N T1s. Instead of this, if you bundle them all together, you can just ask for one /30 subnet and assign it to the multilink interface. This will save you and them, blocks of IPs required for each serial link.

[jeff]

Thanks for the reply.

Jeff