| The VoIP system is in high speed development with the popularization of IP network, press present use and development trend, only utilize of ITU H. 323 agreement can meet user increased function demand already, increase video person who convey extra service in conveying in pronunciation. So, it is main directions studied at present to adopt SIP agreement and combine the corresponding hardware.This article has explain the technological background of VoIP and development prospect at first, has recommended how to structure VoIP system with SIP. Secondly has introduced QoS mechanism, and has expounded the fact in detail that improves SIP and relevant tactics mechanisms to strengthen QoS. In a workflow of VoIP system , have carried on the comparatively deep argumentation to SIP and QoS. Resource that adopt reserve agreement (RSVP) as standard, ensure conversation quality with the real-time transmission control protocol RTCP that the service quality controls with VoIP.Because of IntServ, different foundation of DiffServ put forward tactics that optimize, comprehensive advantage of the two, use RSVP and independent user's hierarchical tactics at the same time. Use RSVP part reserve resource of router, shake hands to fix SIP agreement for the new rule by oneself partly, in order to send resource reserve signal , stop up as to network , package is it is it predict and notrelevant to punish to go on to lose ahead of time; Use the independent user's hierarchical tactics of port, compare with the package of DiffServ in grades, have described the pluses and minuses each other. The difficult point in the tactics concentrates on RSVP resources and reserves partly and stops up and deals with some mainly.This text mainly puts forward a kind of new settlement tactics in order to ensure QoS, make the function of SIP expanded further on the existing foundation, offer more direct solution. While describing, have introduced technology, standard and SIP agreement inn of VoIP, etc.
|
PDF Full Text Request