A prepaid subscriber is allowed to simultaneously implement multiple services in online charging mechanism of IP Multimedia Subsystem (IMS). It is a noteworthy discussion to effectively distribute the limited account ...A prepaid subscriber is allowed to simultaneously implement multiple services in online charging mechanism of IP Multimedia Subsystem (IMS). It is a noteworthy discussion to effectively distribute the limited account resources among concurrent services. An account-sharing algorithm is proposed for multi-services,which introduces resource reclamation and redistribution processes based on the resource reservation of standard specifications and dynamically adjusts them according to the changes of Quality of Service (QoS). Three performance indexes are investigated in the simulation experiments, which are average number of accommodated sessions, average number of completed ses- sions, and average number of iterations per accommodated session. The results show that in the normal QoS level, the three indexes of the proposed algorithm averagely increase by 18.7%, 5.4%, and 3.1% compared with the Prepaid Credit Distribution (PCD) algorithm, and by 2.1%, 1.0%, and 1.8% compared with the Prepaid Credit Reclaim (PCR) algorithm. In the poor QoS level, the performance advantages are greater, which averagely increase by 29.1%, 7.1%, and 2.8% compared with PCD, and by 9.4%, 4.1%, and 3.6% compared with PCR.展开更多
This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location managem...This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location management.The new mechanism aims at improving session setup procedure by a betterment of location management in IMS.Through the use of two-tier subscriber information database constituted by the HSS(Home Subscriber Server) and the VSS, the new mechanism seperates the registration procedure and location management from the S-CSCF(Serving-Call'Session Control Function), and makes them be handled by the VSS.At the same time, the new mechanism updates the signaling procedure of registration and session setup.With VSS based location management, the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower.The cost and delay functions of the new session setup mechanism as well as the cost function of new registeration are deduced.Then, simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.展开更多
基金Supported by the National Natural Science Fund for Distinguished Young Scholars (No.60525110)the National 973 Program (No.2007CB307100, No.2007CB 307103)the Development Fund Project for Elec-tronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘A prepaid subscriber is allowed to simultaneously implement multiple services in online charging mechanism of IP Multimedia Subsystem (IMS). It is a noteworthy discussion to effectively distribute the limited account resources among concurrent services. An account-sharing algorithm is proposed for multi-services,which introduces resource reclamation and redistribution processes based on the resource reservation of standard specifications and dynamically adjusts them according to the changes of Quality of Service (QoS). Three performance indexes are investigated in the simulation experiments, which are average number of accommodated sessions, average number of completed ses- sions, and average number of iterations per accommodated session. The results show that in the normal QoS level, the three indexes of the proposed algorithm averagely increase by 18.7%, 5.4%, and 3.1% compared with the Prepaid Credit Distribution (PCD) algorithm, and by 2.1%, 1.0%, and 1.8% compared with the Prepaid Credit Reclaim (PCR) algorithm. In the poor QoS level, the performance advantages are greater, which averagely increase by 29.1%, 7.1%, and 2.8% compared with PCD, and by 9.4%, 4.1%, and 3.6% compared with PCR.
基金National Science Fund for Distin-guished Young Scholars (No. 60525110)National 973 Program (No. 2007CB307100, 2007CB307103)+1 种基金Program for New Century Excellent Talents in University (No.NCET-04-0111)Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)
文摘This paper proposes a novel session setup mechanism in IMS(IP Multimedia Subsystem) by introducing the functional entity termed VSS(Visitor Subscriber Server) which is used to provide registration and location management.The new mechanism aims at improving session setup procedure by a betterment of location management in IMS.Through the use of two-tier subscriber information database constituted by the HSS(Home Subscriber Server) and the VSS, the new mechanism seperates the registration procedure and location management from the S-CSCF(Serving-Call'Session Control Function), and makes them be handled by the VSS.At the same time, the new mechanism updates the signaling procedure of registration and session setup.With VSS based location management, the cost of registeration and session setup procedure as well as the delay of session setup procedure become lower.The cost and delay functions of the new session setup mechanism as well as the cost function of new registeration are deduced.Then, simulations and analysis verify that the performance of this new mechanism gets the benefit in cost and time.
