Under the old area system, the brigade extension platoon in the area signal company provides signal facilities to the brigade. The area telephone system is common-user. It is automatically switched and designed as transparent to the users. Dial-up services include not only voice service but also data transfer and facsimile. The services also include other forms of electronically formatted information.
Subscribers install local telephone circuits to the junction boxes.
Secure multichannel LOS communications terminals for access to the automatic switched network. The LOS multichannel is the most common and most frequently used system in the brigade. The BSA is normally in the brigade multichannel system in the initial deployment of the multichannel system. However, this depends on the timing of the BSA moves through the operational area. It also depends on the BSA locations relative to the threat force.