Ip Quality Of Service (qos) Techniques

Nowadays, with the development of network, the number of user and the size of network are getting larger and larger. Because the use of network becomes wider and wider and the network traffic is larger and larger, people request network communication has a high level quality. The rapid development of the communication network and the increasing popularization of service level agreement(SLA)make it possible that we transmit realtime service in the connectionless IP packet network. Many international organizations, communication equipment producers and service providers are researching and implementing the way to improve IP quality of service(QoS). Now IP QoS has became one of the focus of IP network researching field.Multiple protocol label switch(MPLS) is a kind of technology that can support IP QoS very well. It can be used together with other technology that support IP QoS. Cable access TV(CATV) network is a very invaluable network resource. Its channel has a very wide bandwidth and good stability. Meanwhile CATV network has a wide popularization and we needn't spend much cost to build new network. So if we can use the CATV network as a backbone network that can transmit IP data, we will improve IP QoS greatly. My article's focus is how to improve IP QoS. Because of the especial interest to MPLS, my article research MPLS-based IP QoS technology deeply. In addition, my article introduce a scheme to improve IP QoS by CATV network and the implementation of IP-CATV/CATV-IP gateway.Chapter 1 gives a brief survey on the tendency of the Internet based on IP and ATM networks and introduce some elements that promote the develop of QoS network. At last it gives the basic concept of QoS and discusses some kinds of technology that support IP QoS and indicate the focus of this article.Chapter 2 studies MPLS protocol in detail. It include the basic idea of MPLS, the architecture of MPLS, the encapsulation of MPLS, the label distribution of MPLS network and the combination of MPLS and ATM.Chapter 3 discusses the means of MPLS supporting IP QoS. It explain that how MPLS support IP QoS from integrated services (IntServ), differentiated services(DiffServ) and explicit congestion notification(ECN) that are supported by MPLS.Chapter 4 researches two algorithms for improving IP QoS under MPLS network and gives the simulation result. One is QoS-based routing algorithm, the other is QoS-based forwarding algorithm.Chapter 5 provide a solution to improve IP QoS by IP over TS technology under CATV network and present the implementation of IP-CATV/CATV-IP gateway based on MPC860 embedded system.