What is a redundant T-1?

Question

My assignment says something about a connection to the outside world is via redundant T-1s to an ISP. What does that mean?

Answer 1

A T-1 or DS-1 is a standard voice/data transmission unit of measure. It refers a tariffed rate at which up to 24 channels can be multiplexed into a single tranmssion unit of up to 1.544 Mbps or indivaidually at 18.8 Kbps. The circuit can be provisioned to carry voice telephone calls (up to 24 lines) or data traffic such as Internet access or point to point data transmission for business's.

When reffered to as redundant it means that two T-1's are deployed to a single ISP to provide internet access using seperate carriers such as AT&T and Sprint to provide back up links for the ISP subscriber should one carrier or the others circuit fail. Thus providing a higher instance of up time than could be expected from a single carrier connection.

Answer 2

You need to set up a redundant connection from your local area network ( or perhaps you WAN --not enough info in your question) via multiple t1 lines to an ISP who will connect you to the internet. T1 lines represent a bandwidth and speed of the required conncection. ( other possibilities could have been oc3 or t3 lines)

Answer 3

I think they are referring to failover, meaning that if the T-1 failed the router would automatically switch to another working line. This second line could be anything from a dial up to a full T depending on how much you want to spend on redundancy.

Answer 4

Usually companies will have 2 T-1's from different providers and in the router set it up so that if the first one fails the second one automatically takes over and the users don't notice any interruption.

Answer 5

its a secondary line in case the first one goes down