net physical link speed could vary from 1M bps to 10G bps, when the physical medium has a range from bulky coaxial cable to optical fiber. Possible Ethernet Physical Link Rate Standard 1Base5 802.3 10Base5/2/T/F/FB/FL 802.3 100BaseT/TX/T4/T2 802.3 1GBaseT/SX/CX/BX10 802.3 10GBaseSR/LX4 802.3ae 100GbE 802.3ba Table A.1: Ethernet Physical Link Rate and Standard 100 Gigabit Ethernet or 100GbE is an Ethernet standard presently under early development by the IEEE. The fastest existing standard is 10 gigabit Ethernet. In late November 2006, an IEEE study group agreed to target 100 Gbps Ethernet as the next version of the technology. A.5 Random Early Detection and Weighted RED Random Early Detection (RED) is a congestion control algorithm to be used in network routers and gateways that may drop (or mark) packets randomly before buffer overflow. Packets are dropped in a probabilistic fashion before the queue reaches an overflow state. randomly dropping packets prior to periods of high congestion, RED tells the packet source to decrease its transmission rate. RED was proposed by Floyd and Jacobson [FJ93] as an effective mechanism to control congestion in the network routers or gateways. Currently it is recommended as one of mechanisms for so-called active queue management by IETF (see Braden et al. [BBC*98].) and it has been implemented in vendor products. In addition, RED has been incorporated in various drafts for Differentiated Services for the Internet in such a way that RED operates on different flows with different parameters depending on the flows' priority, i.e. RED is used to provide different classes of services. Appendix RED is the probabilistic discard or marking of packets as a function of queue fill before overflow conditions are reached. Random dropping takes place when the algorithm detects signs of permanent congestion. The congestion control variable in RED is the average queue size that is calculated from the instantaneous queue size by using exponential averaging. Persistent congestion results in an in