Performance evaluation of datagram congestion control protocol for SIP signalling using NS-2 simulation

The use of Internet-Protocol (IP) Based, combine the transmission of multimedia communication service signalling with other internet based service within the same infrastructure. UDP as the default signaling transport protocol for SIP based mutlimedia communication signalling brings an issue of call drop possibilities during network congestion, leads to impossibility to realize reachibility of service. The paper aims to present the idea of using Datagaram Congestion Control Protocol as signaling transport protocol for SIP based call control protocol to overcome the issue of call drop regarding to network congestion. It assumed that DCCP has a solution to detect network congestion that leads the upper layer protocol from sending an application traffic when the congestion occurs. To proof the concept, the simulation study was performed to run SIP module on NS2, with independently developed DCCP SIP module. The obtained result indicate that DCCP has been more reliable to avoid call drop event due to network congestion compared to UDP. On the other hand UDP as a transport signalling protocol still have a better performance regarding SIP call setup delay than DCCP.