Have been approached with the idea of using a TSIP and losing our traditional carriers. Here is the situation, we have 10 T-1's across 4 sites ld/toll free, have went to the carriers and said i can guarantee you X amount of toll free traffic can you waive the charges for the T-1 ($450/month) they say no. So now looking into using a TSIP where can front end the traffic with an Asterisk or similar system and can not only reduce costs but also have my own in the cloud DR plan via the Internet. Have dedicated internet for Voice only at all locations. Have been running call center via IP Telephony for the last 5 years with no issues as we have dedicated network for Voice and separate for data.
looking to see if anyone else has heard of this or is even using it and how is it working out.

Adrian