Data applications have different QoS requirements depending on whether they are interactive or batch. Interactive data applications usually have a human user at one end of a flow and the IP packets must flow in both directions for meaningful work to happen. For example the user takes some action sending a packet to a server before the user sees more data on the screen the server must send a packet back. The TCP/IP defines a multiplexing network as a special address in each network. This multiplexing could be used as the destination address in a packet and the routers would forward a copy of that one packet to all hosts in that fiber optics medium. A generic reference defined by Layer 3 protocols that do not have to be concerned with the physical details of the underlying physical media Used mainly to contrast these addresses with data link addresses. In this paper our focus will be on one aspect of this subject to provide reliability on WDM based networks. The use of WDM at both transmitter and receiver clearly provide enhanced performance over diversity systems where either the transmitter or receiver.
WDM, QoS, LOS, DSL, MAC.