Bonding T-1s as a cheaper alternative to DS3

We are adding an additional T-1 to our existing T-1 connection to the Internet. We would have liked to have installed a fractional DS3 but the installation and ongoing costs were just to much for us at this point. The ISP that we use has talked about "bonding" the T-1's together so that they appear as one logical internet connection. Is this the best way to go or is there another way to do it?
--Via the Internet.

One term that your ISP should have used in this conversation is NxT1. This better explains the "bonding" phrase that they also mentioned. This can be done with Cisco routers at each end of the connection. It may be doable with non-Cisco routers but I am not familiar with doing it that way. In the NxT1 configuration when I have implemented it, you basically turn on CEF (Cisco Express Forwarding)to do packet load balancing between your T-1 connections. The beauty of this configuration is that you can looe one of the T-1's and all you will see is a slowing down of your internet connection. The only downside I have seen is when one of the T-1's goes up and down repeatedly. When this happens, the router gets a little confused because of the constant change in state of the T-1s.

One thing that I would recommend is to have the ISP send you a configuration of what they would expect the router configuration to look like at your end of the connection. If they balk at this, tell them you want to set up the router in exactly the same way as if they were doing it so that you will have a minimum of problems when converting over the connection to the NxT1 configuration. While it shouldn't be a big deal, see if they will tell you the router model number and IOS version (assuming both of you are using Cisco). Having both the routers on as nearly the same version of IOS could help avoid some problems depending on the amount of traffic you will be generating.

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We are adding an additional T-1 to our existing T-1 connection to the Internet. We would have liked to have installed a fractional DS3 but the installation and ongoing costs were just to much for us at this point. The ISP that we use has talked about "bonding" the T-1's together so that they appear as one logical internet connection. Is this the best way to go or is there another way to do it?
--Via the Internet.

One term that your ISP should have used in this conversation is NxT1. This better explains the "bonding" phrase that they also mentioned. This can be done with Cisco routers at each end of the connection. It may be doable with non-Cisco routers but I am not familiar with doing it that way. In the NxT1 configuration when I have implemented it, you basically turn on CEF (Cisco Express Forwarding)to do packet load balancing between your T-1 connections. The beauty of this configuration is that you can looe one of the T-1's and all you will see is a slowing down of your internet connection. The only downside I have seen is when one of the T-1's goes up and down repeatedly. When this happens, the router gets a little confused because of the constant change in state of the T-1s.

One thing that I would recommend is to have the ISP send you a configuration of what they would expect the router configuration to look like at your end of the connection. If they balk at this, tell them you want to set up the router in exactly the same way as if they were doing it so that you will have a minimum of problems when converting over the connection to the NxT1 configuration. While it shouldn't be a big deal, see if they will tell you the router model number and IOS version (assuming both of you are using Cisco). Having both the routers on as nearly the same version of IOS could help avoid some problems depending on the amount of traffic you will be generating.

Implementing an NxT1 configuration should be pretty straightforward. One reason to look at a fractional T3/DS3 is the amount of phone traffic that you currently have and routing that same traffic over the unused portion of a T3/DS3 instead of having multiple ISDN/T1 PRI (or" voice T-1s" as some carriers call them). When you can combine data and voice traffic on the same cable/fiber pair, there are sometimes cost savings over the additional charges for separate circuits for voice and data.

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