Voice Over Internet Protocol (VoIP) and Security

........................................................................................................................1 Background ..................................................................................................................1 Quality of Service .........................................................................................................1 Latency .......................................................................................................................2 Jitter............................................................................................................................2 Packet Loss ................................................................................................................3 VoIP Components.........................................................................................................3 End-user equipment....................................................................................................3 Network components ..................................................................................................3 Call processor .............................................................................................................4 Gateways....................................................................................................................4 Protocols.....................................................................................................................5 H.323.......................................................................................................................5 H.323 Security Concerns .....................................................................................6 SIP ..........................................................................................................................6 SIP Security Concerns .........................................................................................7 NAT and VoIP................................................................................................................8 Denial of Service...........................................................................................................8 Other Concerns ............................................................................................................9 Conclusion..................................................................................................................10 References ..................................................................................................................11