network auditing

The objective of this book is not to discuss every QoS feature in isolationplenty of material available in the industry accomplishes this. The goal instead is to show how these techniques are used in a holistic network design to achieve end-to-end QoS for the entire network. Another objective of this book is to show how to deploy QoS not only for purposes such as maintaining voice quality for VoIP calls, but also to show how QoS can be used to achieve such goals as protecting the network against denial-of-service (DoS) attacks and managing traffic flows to keep unwanted traffic (such as copyright-infringing music file-sharing applications) off the network auditing.

Loss causes voice clipping and skips. Network auditing is a technique used to mask the effects of lost or discarded VoIP packets. The method of PLC used depends upon the type of codec. A simple method used by waveform codecs such as G.711 (PLC for G.711 is defined in G.711 Appendix I) is to replay the last received sample with increasing attenuation at each repeat; the waveform does not change much from one sample to the next. This technique can be effective at concealing the loss of up to 20 ms of samples