When the optional extra G3 Interface Unit is installed, communication can take place at the same time through the two or three lines at once.
Option | Available Line Type | Available protocol Combinations |
|---|---|---|
Standard only | PSTN | G3 |
Extra G3 Interface Unit (single) | PSTN + PSTN | G3 + G3 |
Extra G3 Interface Unit (double) | PSTN + PSTN +PSTN | G3 + G3 +G3 |