A Local Area Network as a Telephone Local Subscriber Loop

The technical feasibility, of utilizing a local area network (LAN) as a multidrop local subscriber loop for a PABX is shown. The network capacity is found through simulation both with a contention protocol (CSMA/CD) and a virtual token protocol (GBRAM) used for media access. It is shown that a stable configuration, utilizing distributed call blocking procedures, will result in less than two percent of the voice packets being lost during busy periods. Listener tests with a packet phone and dropped packets confirm that this is acceptable to the user.

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