[Asterisk-Users] How to use multiple VOIP provider trunks

[Damon Estep]

<snip>

> I am working on a phone routing system (with 
> duplicate/redundant routes) and I will just have a way for a 
> user to tell the system that they want to use an alternate 
> route for the next call.

How about the simple and traditional method,

Dial 9 for an outside line, dial 8 for an alternate outside line? Or
dial nothing for an outside line, dial 9 for an alternative outside
line.