The TUNEL unit is a transmission card that allows the 8Mbps G.703 transmission of up to four 2Mbps signals. Each unit has two 8Mbps G.703 ports which can be individually activated and configured.

Example Applications

Thru connection of 2Mbps signals:- Any of the four 2Mbps signals can be transparently switched from one port to the other without being internal connected.

Drop and insert:- Any of the four 2Mbps signals can be dropped from one port and connected to the internal backplane where the 31 time slots can be accessed.

1 + 1 signal protection:- TUNEL to TUNEL operation can be configured for 1 + 1 protection. The 2Mbps signals are connected on both ports, one port is the primary carrier and the other is used as a backup.