Current local area network (LAN) bandwidth demands of > 1 Gb/s are pushing the limit of the bandwidth distance product of multimode fiber. In order to overcome these limitations, a low-cost, compact wavelength-division-multiplexing (WDM) scheme is demonstrated. Aggregation bit rate of 5 Gb/s are achieved through 100 m of 62.5/125-µ m multimode fiber which are used at 820, 840, 860, 880 nm with each operating at a bit rate of 5 Gb/s. This technology provides a practical solution for reaching bit rates up to 10 Gb/s in the LAN. The possible angular misalignment effects in fiber-optic coupling and alignment process is also identified and evaluated for the development of low-cost fiber-optic component manufacturing technologies. It is further demonstrated the design and implementation of a novel multiple-wavelength optical data link for low-cost multi-mode wavelength-division multiplexing (WDM) local-area network applications.