Bandwidth optimizer for VOIP voice traffic

We want to build an Asterisk bandwidth optimizer for VOIP voice traffic - using IAX. This will use standard software, we assume linux and IAX. (We are open to suggestions.) We want to hire someone who has already done this. If you haven't already done this before don't bother applying please. We want something similar to SBO or RBC Tech. ( [login to view URL] [login to view URL] ) Our main goal is to minimize the bandwidth on the client side while maintaining voice quality. We also want the solution to include VPN capability - to be able to securely send the traffic. We need some kind of bandwidth compression system from Box A to Box B. We believe the latest version IAX is the best. Box A = Master Box in a data center with static IP. (Presumably an asterisk server.) Box B = Client box at a small location usually with a dynamic IP. (Presumably an Asterisk Client server.) Typical scenario: 1. Box A (Master asterisk server, with static IP) Calls come in to Box A over the sip protocol from a VOIP Switch. We use codecs G729 and G723. Box A then sends the calls to Box B - and we want it to do so using compression. 2. Box B (Asterisk client server with PRIVATE NETWORK IP), receives calls from Box A on the WAN side, and sends the calls to a gateways on the LAN side using SIP. 3. Numbers of Box B can be unlimited. (At least 100 boxes.) 4. Numbers of Gateways per Box B can be unlimited (In practice a solution serving only 1 box is helpful - however we really would like a Box B to serve multiple gateways.) 5. Box A to Box B voice traffic will usually be encrypted. We would like a VPN between the two boxes. Obviously one of the ends will probably have a dynamic IP address. The VPN will transport voice traffic - IAX trunks in trunking mode. 6. Asterisk sip trunks to connect to the gateways. Deliverables Include: IAX2 Transport Multiple interfaces on WAN and LAN side Ability to switch between WAN interfaces (without dropping the call.) Port forwarding non voice IP traffic through the device. (We can explain.) Easily deployable and configurable on to a new box. We plan on using Dell PCs. We assume the solution will be linux. (If possible we would like boxes with two NICs, but that is optional.) Documentation on how to configure and install etc. (We also want to understand how the routing would work.) The master Box A does have to serve multiple clients. Master Box A should be able to have multiple IP addresses. Each client Box B must be able to support at least one gateway. We really want it to support more than one. Each client Box B can 'phone home' to the master Box A. Easy way to change the IAX IPs and Ports. We will be testing the bandwidth compression from SIP to IAX. Also will test for VPN overhead. We can also provided dedicated boxes for testing and development.