MCDQDB (multi-channel DQDB) using WDM (wavelength division multiplexing)

The applications such as real-time video/voice service, distributed multimedia database access, and high-resolution image transfer require more bandwidth than are available today. These applications also require large geographical span. To meet the requirements, we introduce the new protocol, MCDQDB, for multi-channel dual-bus MAN which is the extension of a single channel DQDB MAN. MCDQDB can be easily implemented with the state-of-the-art WDM technology and conformed to the IEEE 802.6 standard, DQDB, with the improvement of fairness and access delay. The multiple channels of MCDQDB are made by WDM and the nodes of MCDQDB have the fixed transmitters and the fixed receivers whose number is equal to the number of channels. Better fairness is obtained by distributing head-end nodes. For analysis, we compare MCDQDB with DQDB with a high speed channel. The simulation results show the advantage of MCDQDB in access delay and fairness, compared with one channel original DQDB and the relation between the number of channels of MCDQDB and the channel speed of DQDB.