Internet is evolving into a global commercial infrastructure, growing in size physically and reaching even to the most remote places on earth. Day to day the services provided by the internet and its users are also increasing thereby different kinds of data (e.g. Video, audio, text etc) are to be handled by the network. Thus increasing the data traffic in the network. The unpredictable and burst nature of computer traffic not only prevents the network from making quality assurance, but also creates the problem of congestion. Queue management at the router plays an important role in controlling the congestion. There are already many algorithms proposed (e.g. Drop Tail, RED, Random Early Drop etc). Every queue management scheme has its pros and cons. The choice of algorithm to be chosen depends on the user requirements and demands.

The proposed work analyzes the performance of different queue management schemes. Core Stateless Fair Queuing (CSFQ) guarantees the fair bandwidth allocation with low cost and less complexity. In order to evaluate the CSFQ scheme, simulations are used. In these simulations, the performance of parameters like packet drop and delay are compared with existing schemes such as RED. This work also analyzes the performance of packet marking schemes in differentiated services. These marking schemes provide the differentiated services for different classes of data. Performance analysis of two marking schemes SRTCM and TRTCM is evaluated.

All Simulations are performed in NS-2 on LINUX platform. Performance of schemes is evaluated by varying the parameters such as link bandwidth, link delay and CBR rate.