We are in the process of connecting to France Telecom as our first mile provider using DS3 link. We are both using Cisco Router with different model and also with different Network Modules. France Telecom is using 7613 and we are using 3825.
France Telecom uses PA-2T3 and we are using NM-1T3/E3 NM. However, when we are about to test our end-to-end testing, the serial interface is in "down" state and it is never going up. On the other hand, when I set it to loop back it is working and so I believe our network module is working. FT however, also did the same thing and their loop back also worked.
We are both using HDLC encapsulation and we have verified our parameters we have on both sides. Are we missing something?
Your kind reply and assistance on this matter is highly appreciated.