A terminal A and a MCU are distant, not in the same province, use ISDN mode to create networking, the terminal can’t call through the MCU, but can call through the local terminal B of the MCU.
Terminal A call through terminal B, found the respond calling number area code is different with the location of the area code of the terminal A form the terminal B diagnostic window. The area code is Province S area code XX. Change the Terminal A telephone area code parameter into XX in the MCU venue list. After modified, the terminal A is able to call through the MCU
No open direct ISUP signaling between terminal A and the location that MCU in. To meet the needs, the bureau which Terminal A there do the data, transfer route to the province S (the lines between the Provincial S and the two places can meet the need) ,then arrive to the bureau that the MCU in. The Province B long-distance bureau transform the terminal A corresponding ISDN phone number area code. When terminal A call MCU, MCU received calling number area code are The Province B telephone area code. MCU venue parameters have no appropriate configuration, still is the area code that where terminal A in.