The recent decades have witnessed enormous development in communication world; especially in internet technology that has played an important role in moving forward the human communications, with such development user demands better communication services such as video conferencing. Video conferencing becomes more popular nowadays since it can break the constraints on the communication ways of people who are probably exist in diverse geographical locations in real time. SIP is preferred to be used as signaling protocol for video conferencing, but still using SIP for video conferencing is affected by the delay which reduces the satisfaction of user as it decreases the QoS. This thesis work is aimed to study the performance of SIP signaling for video conferencing, and also describing the causes of the delay in SIP session establishment and termination. The literature review and the two simulations have been carried out in this thesis to examine the effect of specific parameters on the session setup delay. The first study is carried out by using ns-2 to simulate different transport protocols and study their effect on session setup delay. The second study is carried out by using SIPp to achieve two objects. The first object is to study the relationship between number of simultaneous calls on both the session setup delay and call release delay, while the second object is to verify the result of changing transport modes of transport protocol for both session setup delay and call release delay. The results obtained from first simulation showed that utilizing UDP as transport protocol will return less session setup delay than TCP and SCTP. The first objective of the second simulation results clarify the relationship between number of simultaneous calls on both the session setup delay and call release delay which was directly proportional; on the other hand the second object showed that by using UDP in mono socket mode has less session setup delay and call release delay.