LARNet, a wavelength division multiplexed network for broadband local access

Abstract

We present a wavelength division multiplexed (WDM) network architecture for local access that provides broadband switched services. A central office (CO) is connected to multiple optical network units (ONU) through a shared access fiber and a passive router in a remote node (RN). A single multifrequency laser (MFL) in the CO sends data simultaneously on all wavelengths; spectral slicing and a WDM receiver is employed for upstream connectivity. The WDM layout ensures independent virtual point-to-point links up-and downstream; expensive components are shared among all ONUs; and the wavelength control problem becomes very simple. The ONU is built with inexpensive commercially available components. Aggregate rates of several Gbps downstream and several hundred Mbps upstream can be realized.