QoS Control Technology In The UMTS Environment, The Application Of Research

The development of wireless communication network is rapidly in recent years. Wireless communication systems based on circuit switching will gradually replaced by all-IP networks. UMTS, which is the main standard of 3G, is emphasized both by the network designers and the operators. The core technology of IP QoS controlling, is always a highlight problem in the research of computer internet and multimedia communication.The thesis extends around this subject—'QoS guarantee in UTMS', introducing the current research state of QoS , then further discussing the IntServ model and DiffServ model raised by IEIF. DiffServ does not need complicate signaling and has good expansibility, better satisfying the requirement of core network. But IntServ has better performance in the realization of service quality. The research tendency of this paper is using DiffServ in core netword and IntServ/RSVP in wireless access network to implement mobile admission control and resource dynamic allocation.Flow control subsystem is an essential part of DiffServ. In this paper, we study and compare many algorithms such as TrTcm, We implement the SrTcm algorithm and then simulated it. Congestion management subsystem includes the three parts—queue management, congestion avoidance and queue scheduling. We study the LXP2400 internal integrated hardware unit supporting queue operation and queue management's principle. We implement and simulate the WRED algorithm to prove the well performance of this scheme. At the end we raise a new algorithm to deal the congestion question to avoid the global synchronization question and make it easier to control the stream.In the last part, a combining IntServ model and DiffServ model is designed to aim at different QoS requirements of various UMTS services, raising relative business mapping, queue scheduling, flow regulation etc. In conclusion, we proved the efficiency of the new model of combining IntServ and DiffServ with the new scheduling algorithm.