Overload Protection in a SIP Signaling Network

The paper studies performance of a SIP signaling network in an overload condition. The main interest is to find a preferable queuing structure of a SIP proxy server to protect from performance degradation. In the study, two types of queuing structure, which are a simple single FIFO queue and a two class priority queue, are considered. Using the network simulator (ns-2), the paper evaluates a throughput. The simulation study shows that in case of the single FIFO queue, the throughput decreases drastically when an overload is applied. The paper shows that the priority queue protects from performance degradation and improves the throughput. The paper shows a preferable queuing structure of a SIP proxy server for overload protection.