Date Added: Jun 2011
Over IP network the SIP-based VoIP system build, so it is precious by the IP network security problem. In this paper, the authors concentrate on the issue of Denial of Service (DoS) attacks which targeting the hardware and software of voice over IP servers .In this situation, they mainly identify attacks based on exhaustion the memory of VoIP servers, attacks on the CPU. A major conclusion is that SIP provides a wide range of features that can be used to accumulate DoS attacks. Discovering these attacks is inherently difficult, in the case of DoS attacks on other IP components. With sufficient server design, implementation and proper hardware the effects of a large portion of attacks can be reduced.