Telephone Networks
Digital PBXs have three major characteristics:
- nonblocking operation means that intraoffice calls can always be replaced between any two telephones within the organization
- integrated voice and data means that voice and data can be transmitted over the same communication circuit and through the same PBX
PBX based local area networks (star network)
Cellular technology is a form of high frequency radio in which antennas are spaced strategically throughout a metropolitan area
A service area or city is divided into many cells, each with its own antenna for reliability
A cellular telephone network is intelligent (when a signal weakens the system begins to pick up your signal at the second antenna automatically)