How exactly does the bonding work with regards to the AT&T system?
If you had a single line with AT&T, your DSL line connects to a DSLAM which then connects to a gateway (redback or BRAS). between the DSLAM and gateway, your data traffic consists of ATM cells and after the gateway it is TCP/IP packets.
So does the bonding simply aggregate/disaggregate the packet traffic across the four lines at Shareband routers which would be manipulating the data beyond ("above") the AT&T gateway or is there any way they could fragment the TCP/IP packets so that it would affect the ATM cells "below" the gateways?
If it is the former, I don't see how this could be a gateway problem. More likely it seems that it might be transmission delay problem over an internet backbone or the routers along the backbone after the packets leave your NOC and before they arrive at the Shareband routers.
For curiosity's sake, you might try the Wireshark test and post the results here. I'd expect the results to be incomprehensible due to the added complexity of the line bonding, but you never know what might show up.--
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