Interesting question

[compufxr]

I have a client that is in a building that has managed telephone services. The building has a call manager and 10 T-1's for call traffic. Currently, 6 T-1's are being used for outbound and 4 T-1's are being used for inbound traffic. The 6/4 T-1's are from different providers (i.e. the 6 outbound are from one company and the 4 inbound from another provider).

The questions I have are as follows:

1. Why would you want to separate inbound and outbound traffic like that?

2. Can't you use either of the T-1's for both inbound and outbound traffic?

3. What would happen if all of the inbound (or outbound T-1's for that matter) went down? Can the other T-1's take over as a failsafe? What is required for that?

4. If a failure does occur how do the DID's know where to go? Aren't the DID's down since the T-1 is down?

5. What can be done to insure uptime and create a failsafe so that phone service does not go down inbound or outbound?

Thank you all in advance.

Paul

 

[jeter]

The only reason why I think people do this is because they think there is a reliability using different providers.

All your other questions can be answered by using PRI's each providing their own D channel for signaling and bound together...

“Reserve your right to think, for even to think wrongly is better than not to think at all”

Tek-TIP Member 19,650

 

[crystalfusion]

1. Why would you want to separate inbound and outbound traffic like that?

-- Costs maybe. Different vendors offer differnet prices, right?

2. Can't you use either of the T-1's for both inbound and outbound traffic?

-- Might be able to. Depends on what the provider is giving. Most likely they can use it in both directions and choose not to.

3. What would happen if all of the inbound (or outbound T-1's for that matter) went down? Can the other T-1's take over as a failsafe? What is required for that?

-- Would need to add call routes and priority. Don't think you can configure for only failover.

4. If a failure does occur how do the DID's know where to go? Aren't the DID's down since the T-1 is down?

--The DIDs need to be registered on both telco provider switches. Thats where the redundancy comes in. If they support it.

5. What can be done to insure uptime and create a failsafe so that phone service does not go down inbound or outbound?

-- Seperate the two as much as possible. A basic setup: 2 T1s from each carrier. 1 from each into seperate 3845 routers with SRST. 3845 has redundant power. Switches could be 4507R or 4510R with redundant supervisors and power. Then have a CCM cluster.