From being primarily a technology for transport networks, optical technologies are steadily gaining terrain within both metro and access networks. Wavelength Division Multiplexing (WDM) is the technology enabling cost efficient upgrade of capacity in optical networks. This whitepaper explains the fundamental principles for optical networks, and discusses critical factors in deploying optical networks. Unnecessary use of routing and switching resources can be avoided using optical networking techniques for building an optical aggregation network.
Principle and applications of Coarse WDM (CWDM) and Dense WDM (DWDM) are explained and important demands to installations and fibre infrastructure is discussed in relation to channel bitrates up to 10 Gb/s. For bitrates of 10 Gb/s, WDM multiplexer insertion loss is shown to become a critical factor because of the more stringent link-budget on 10 Gb/s compared to 1 Gb/s. The importance of low insertion loss WDM multiplexers is also shown to be a critical factor in optical aggregation networks. The low insertion loss of TransPackets multiplexing and demultiplexing units enables both long distance 10 Gb/s transmission and scalability in optical aggregation networks. Furthermore, while DWDM have been known to be much more expensive than CWDM, TransPacket’s low-cost and low insertion-loss DWDM products enable cost efficient solutions for networks where deployment of more than 8 wavelengths is desirable.