When you order an MM710 T1/E1 Media Module, you must include the optional 700A loopback jack. With the loopback jack installed, you can loop back the T1 up to the network facility without a dispatch. If the MM710 is sold with an Avaya Service Agreement, the jack must be ordered and installed to save time and money on service calls.

The jack is usually used for CO trunk installations. The jack is inserted as close to the network or service provider T1 facility as possible. When the jack is activated from the gateway, the jack sets up loopbacks in both directions. The gateway can then send and receive a test pattern. The test pattern verifies the function of the MM710 and T1 cable up to the network T1 facility. In normal operation, the jack passes the T1 signals through undisturbed in both directions.