Time division multiple access (TDMA) multiplexing of ATM cells from thousands of residential customers toward the common feeder of a passive optical network (SuperPON) tree obviates the need for an equal number of optical line terminations (OLTs). All upstream transmissions converge by means of the passive splitters/combiners to just one OLT unit which serves all by time sharing. The ability to reach such a high splitting ratio became possible by the development of bursty mode optical amplifiers (OAs). In addition, OAs make possible a 100-km-long feeder which can bypass the local exchange into the first core switch, bringing further savings to both initial and running costs. These techniques allow SuperPONs to lower the access cost per customer, holding for the promise of ushering into domestic local loops the photonics revolution which has already transformed the transmission plant. These savings, however, can only be realized under the assumption that the system can accept high loading before exceeding the limits of quality of service (QoS) requirements and without distorting the egress traffic in a way that jeopardizes the statistical estimates on which ATM connection acceptance was based. Solutions to the problem of traffic arbitration, respecting the idiosyncrasies of each traffic class and suitable for fast implementation, are offered.

The SuperPON is an extension of the concept of the passive optical network (PON) based on the use of optical amplifiers which greatly increase the available power budget. This extra power is exploited to increase the range up to 100 km and the splitting ratio to reach 2000 network subscribers. The impact on the MAC of this high number of units compared with regular PONs is quite strong requiring the combination of quite different access mechanisms to satisfy the diverse quality requirements of residential services. Such a protocol is proposed.

Connectionless (CL) services as already developed in LANs, have to interwork with emerging asynchronous transfer mode (ATM) connection-oriented (CO) networks. MANs are a significant evolutionary step and CO MANs, in particular, constitute a technically appealing method to integrate both environments and provide shared medium access for all services. The functions required for enhancing distributed-queue dual-bus (DQDB) MANs with CO services in a way compatible with ATM are described. Within the integrating framework of B-ISDN, the practically useful scenarios for interworking LANs, CO and CL MANs, and ATM are investigated and classified in order to exploit the advantages of an efficient protocol relay utilizing the resources of the lowest possible layer. This is aimed at assisting interworking unit (IWU) designers and implementors to decide on key options in this versatile and evolving environment. The CO DQDB case emerges as the most advantageous development in terms of interworking simplicity and robustness.>

The authors examine the internetworking of the distributed queue dual bus (DQDB) metropolitan area network (MAN) with asynchronous transfer mode (ATM) of broadband integrated services digital network (B-ISDN). Several scenarios are discussed. It is suggested that the best solution is through the use of a connection-oriented (CO) DQDB service. Some of the provisions of the CO DQDB service necessary for an efficient and simple interworking are provided.>

The cost of a dedicated fiber access to the B-ISDN is too high for small business and residential customers, necessitating some form of resource sharing. Combining ATM over a passive optical network (APON) with a suitable medium access control (MAC) protocol can provide significant cost savings and a reasonable bandwidth. In this way, this customer section can also enjoy introduction of broadband services at a relatively early stage. The emphasis of the MAC protocol presented is placed on service transparency with an aim to incur minimal changes to the local exchange (LEX) when an APON is attached. Sharing is effected by a reservation-based time division multiple access method.>