A TDMA BASED ACCESS-CONTROL SCHEME FOR APONS

The cost of a dedicated fiber access to the broad-band integrated serv ices digital network (B-ISDN) is too high for small business and resid ential customers necessitating some form of resource sharing. Combinin g the asynchronous transfer mode (ATM) over a passive optical network (APON) with a suitable medium access control (MAC) protocol can provid e significant cost savings and a reasonable bandwidth. In this way the customer line section can support broad-band services at an early sta ge. The MAC protocol presented in this paper places emphasis on servic e transparency aspects with an aim to incur minimal changes to the Loc al Exchange for APON connections. Sharing is effected through a reserv ation based time division multiple access method. The proposed MAC pro tocol is characterized by dynamic bandwidth allocation and multiple ce ll transmissions from each network termination in the upstream directi on. This reduces waste due to the unavoidable synchronization preamble s and other overhead.