communication system

Airbuses have a telemetry system called ACARS, for Aircraft Communication Addressing and Reporting System, which transmits the same data that is recorded on the aircraft's black box. ACARS reported the pitot-static system had failed.

On July 2, the French equivalent to the National Transportation Safety Board reports the plane was intact when it hit the water. Plus, there's a history of pitot tube problems on these planes. So they're working on what they think the actual problem is.

number addressing (NA) is the Internet addressing system which is similar to letter addressing system.

Global Positioning System is a system for determining your position on the surface of the Earth.

As such, other that for reporting your position, it has little use in communication.

GPS is of almost universal use in land surveying, but again, that is not comms.

k