Research On The Guarantees Of QoS In Direct Interconnection Networks

The exponential growth of the Internet is a driving demand for high performance and large capacity routers, so Terabit Router is the trend of next generation of core routers. Switching Fabric, a kernel component in the router architecture, play a key role in the performance of the router. Since Direct Interconnection Network(DIN) has many good characteristics such as good scalability, distribution control, it becomes a good scheme for Terabit Router switching fabrics.The existence of real-time traffic in the network has put forward the requirement of Quality of Service(QoS). However, the traditional schemes(such as switching mechanisms, routing algorithms) in DIN doesn't take into account the QoS requirement of real-time traffic. In this thesis, we carry research on techniques of QoS guarantee in DIN. Three major achievements are outlined as follows.Firstly, based on the research of several traditional switching mechanisms in DIN, we propose a new switching mechanism—Differentiated Cut-Through(DCT) which combines the concept of DiffServ. DCT can gain high throughput and guarantee the Quality of Service for the real-time applications.Secondly, the design of routing algorithm in DIN is studied. Then, A routing algorithm is proposed, which can guarantee the QoS of different traffics.Thirdly, congestion control mechanism in DIN are studied. We analyses several congestion control mechanisms which are very popular nowadays. Also, we propose a new congestion control mechanism which is based on the length of queues for injecting packets. This mechanism can also provide QoS guarantee for real-time traffic.At last, we carry out the simulation in OPNET for the schemes proposed above. The results show that all the schemes can provide good performance for real-time applications compared with that of the traditional mechanisms.