End-tn-End Measurement-Based Admission control

VoIP网络在发生流量拥塞时，可能会出现丢包、时延、抖动等问题，导致语音质量下降。需要进行准入控制，以限制正在进行的VoIP会话的数量，以保持语音传输质量。为此，可以使用RSVP （Resource reservation protocol）等信令协议。由于路由器等转发设备在进行语音通信之前进行了资源预留，保证了高质量的语音质量。然而，这种方法存在可伸缩性问题，因为路由器需要维护每个流信息以进行资源预留。此外，网络中的所有路由器都应该支持RSVP。还有另一种方法称为终点允许控制。这种方法只有源节点和目的节点负责接收控制，中间路由器没有接收控制的特殊功能，具有较高的可扩展性。本研究的重点是端到端基于测量的准入控制和服务质量管理方法。所提出的方法采用一种方法，根据端点之间探测探测数据包测量的网络拥塞状态来决定是否允许呼叫。本研究实现了以下几个目标：1。端到端基于测量的准入控制机制可选路径环境下的准入控制。基于端到端测量的允许控制网络的网络设计。试用phone5。VoIP质量管理系统端到端网络路径的瓶颈带宽测量

When the traffic congestion occurs in VoIP network, voice quality may be degraded due to packet loss, delay and jitter. Admission control is required to limit the number of on-going VoIP sessions to maintain voice transmission quality. To this aim, a signaling protocol such as RSVP (Resource reservation Protocol) can be used. High level quality of voice quality is guaranteed with this method, since the forwarding devices such as the router make resource reservation before performing voice communication. However, this method suffers from scalability problems, because routers need to maintain per flow information for resource reservation. Moreover, all routers in the network should support RSVP. There is another method called end point admission control. In this method, only source and destination nodes are in charge of admission control and intermediate routers has no special functions for admission control, leading to higher scalability. This research focuses on end-to-end measurement-based admission control and quality of services management methods. The proposed method employs a way to make a decision of whether a call can be admitted or not depending on the network congestion state that is measured using probing probe packets between end points. This research has achieved several goals as listed below.1.Mechanisms for end-to-end measurement-based admission control.2.Admission control with alternate path environment.3.Network design for networks with end-to-end measurement-based admission control.4.Trial implementation of phone5.VoIP quality management systemBottleneck bandwidth measurement for an end-to-end network path