Why CWDM?

As the surge for additional convergence technology and increased-bandwidth continues, CWDM Ethernet-over-fiber seems to be a viable solution for service providers.

CWDM involves both sides of the equation. That is, reducing operating costs and increasing revenue. As the traditional service revenue declines, service providers shift their focus on finding new sources of services to develop. The continuation of high-speed services, HDTV, IPTV, VOIP and video-on-demand are all areas designed for revenue growth.

Price elasticity of bandwidth shows that a decrease in the price (from P1 to P2) drives an increase in the quantity demanded (from Q1 to Q2). By lowering the price of high-speed services, and legacy features, service providers can tap new markets and expand their addressable market.

Coarse wavelength division multiplexing (CWDM) is a technology which multiplexes multiple optical carrier signals on to a single optical fiber by using different wavelengths (colors) of light to carry each individual signal. Combining several optical channels, which are separated by a wide spacing and a channel separation of 20 nm. The benefits of using CWDM include increased capacity on routes with fiber exhaustion and a more affordable alternative to installing more fiber or leasing additional fibers.

CWDM can be used in conjunction with a fiber switch and network interface device to combine multiple fiber lines from the switch over one fiber. CWDM is optimized for a cost conscience budgets in mind, with low-cost, small-powered laser transmitters enabling deployments to closely match guaranteed revenue streams..

Service provider networks can be classified into four segments: edge, access, metro, and long-haul. The edge consists of a Customer Premises Equipment (CPE) device with low cost multiplexers. The local aggregation office terminates the CPE equipment, and aggregates signals to be transported to a Central Office (CO). The access-facing portion of equipment in the CO is dominated by Add/Drop Multiplexers. On the outbound links, COs within an area are interconnected, and the long-haul portion of the network is dominated by a DWDM for transport.

CWDM has the advantage in enabling a low-cost solution to transport several services simultaneously without adding additional fiber, and increasing additional capacity on routes with fiber exhaustion.