1. Thursday, 12 July 20071 Quality of Service Provisioning within IMS-WLAN Interworking Higher Institute of Industry Postgraduate Department Prepared by: Asma Abdalla Mustafa Elmangosh Supervisors: Dr. Majdi Ali Altomi Ashibani Dr. Fathi Hamad Ben-Shatwan

2. Thursday, 12 July 20072 Outline  Next Generation Networks.  IP QoS Models.  IP Multimedia Subsystem.  Policy-based Quality of Service in IMS.  Wireless LANs & WLAN-IMS Interworking.  The Proposed QoS Architecture.  Performance Evaluation of Proposed Architecture.  Published Work.  Conclusions.  Further Work.

3. Thursday, 12 July 20073 The NGN Motivation: Any where, any time, any device Access Independent Mobility and QoS enabled IP core Integrated Services

4. Thursday, 12 July 20074 Next Generation Networks (NGN)  A Next Generation Network (NGN) is a [ITU]: A packet-based network provide telecommunication services make use of multiple broadband, QoS-enabled transport technologies. service-related functions are independent from underlying transport-related technologies. offers unrestricted access by users to different service providers. It supports generalized mobility.

5. Thursday, 12 July 20075 Next Generation Networks (NGN)  Advantage: Save costs (ONLY one network to handle). Increase revenues (easy to add more service).  Consequences: Network operators will be degraded to “bit pipes”. IP Multimedia Subsystem A Global Service Delivery Platform

6. Thursday, 12 July 20076 NGN Architecture Transport Plane Core Transport Function Service Control Plane PSTN/ISDN emulation IP Multimedia Subsystem Other Multimedia Components Management Plane Application Plane Access Functions Open APIs & Protocols (JAIN, Parlay, SIP) Access Transport Functions Gateway Functions Edge Functions Subscriber & Service Provisioning, Network Management, Operational support, Billing Support

7. Thursday, 12 July 20077 IP Quality of Service Models Best Effort Internet (No QoS) Full QoS Network (IntServ) Traffic Classes Network (DiffServ) The Internet only makes a Best Effort attempt to deliver packets Signaling: Resources reservation per flow end-to-end. Lack of scalability Simple core /intelligent edges Differentiated queuing/scheduling (per class)

8. Thursday, 12 July 20078 IP Multimedia Subsystem (IMS)  Standard by the 3 rd Generation Partnership Project (3GPP).  IMS is a global, access-independent and standard based IP connectivity and service control architecture that enables various types of multimedia services to end-users using common Internet-based protocols.  IMS is expected to provide the basic architecture framework for the NGN.

9. Thursday, 12 July 20079 CSCF Media Gateway MGCFMRFC PST N Media Server IMS Architecture DAL, 802.11, GPRS, CDMA SIP HSS Transport & Endpoint Layer OSA-GW Supplemental Telephony Services Legacy SCPs IM-SSF Application Servers Parlay API Telephony Services (TAS) Non-Telephony Services Session Control Layer Application server Layer CAMEL, ANSI-41 INAP, TCAP SIP-ISC

10. Thursday, 12 July 200710 IMS Components P-CSCF IMS HSS S-CSCF I-CSCF PS Domain Other IP/ IMS networks Applications Servers The PS domain provides the IP bearer to access to the IMS. The HSS holds the IMS service profile of the subscribers. CSCFs are the IMS entities responsible of the call control: there are 3 types of CSCFs depending on their role: P-CSCF (Proxy CSCF) S-CSCF (Serving CSCF) I-CSCF (Interrogating CSCF) Legacy / PSTN The AS provides value-added services to subscribers. MGW/ MGCF Provides connectivity to external CS networks.

11. Thursday, 12 July 200711 So, Why IMS in NGN?  IMS provides several of the fundamental characteristics of the NGN.  IMS uses IETF standard protocols.  Open interfaces allow for a wider choice of suppliers.

12. Thursday, 12 July 200712 Session Setup IP- CAN HSS Visited Network (Originating) Visited Network (Terminating) Home Network (Terminating) Home Network (Originating) P-CSCFI-CSCFS-CSCFI-CSCFS-CSCFP-CSCF P-CSCF routes the SIP invite to the user’s home domain (I-CSCF) HSS acts as a location server to assist on locating the S-CSCF I-CSCF proxies the SIP invite to the user’s serving S-CSCF routes the SIP invite to the called party’s home domain S-CSCF potentially invokes service profile, but normally forward the SIP invite to the P-CSCF Bearer established directly between user client following successfully signaling

13. Thursday, 12 July 200713 Policy-based Quality of Service in IMS GGSN PEF (Policy Enforcement Function) P-CSCF PDF (Policy Decision Function) UE 3) Request for QoS resources (Authorized IP QoS parameters) 1) SIP/SDP 2) Request for QoS resources (Service Information ) Data IMS Policy decision: Check QoS request allowed according to local policy rules Policy enforcement Resource Reservation

14. Thursday, 12 July 200714 Wireless LANs  Provide LAN functionality without fixed infrastructure using wireless radio technology.  WLAN can ONLY be a complementary technology to 3G.  Two major WLAN standards: IEEE 802.11: The de facto WLAN standard worldwide. HiperLAN. PHY MAC 802.11a {5GHz OFDM PHY} 802.11b {2.4GHz CCK PHY} 802.11g {2.4GHz OFDM PHY} 802.11d {International roaming} 802.11e {QoS/efficiency enhancements} 802.11h {5GHz regulatory extensions} 802.11i {Security enhancements} IEEE 802.11 standards

15. Thursday, 12 July 200715 IEEE 802.11e Distributed Coordination Function Hybrid Coordination Function HCF Contention Access (EDCF) HCF Controlled Access (HCCA) Required for Prioritized QoS services Required for parameterized services

16. Thursday, 12 July 200716 WLAN-3GPP Interworking Architecture WLAN Access Gateway Charging data generation Routing enforcement Packet Data Gateway Charging data generation, IP address management Tunnel termination QoS handling Authentication, Authorization and Accounting server Terminates all AAA signaling originated in the WLAN that pertains to the WLAN UE

17. Thursday, 12 July 200717 The Proposed QoS Architecture for WLAN IMS Access End-to-End Service WLAN Bearer Service External Bearer Service 3GPP IP Access Bearer Service L2/L1 Transport IP L2/L1 Transport IP L2/L1 Transport IP Transport IP L2/L1 Transport IP Tunneling layer Remote IP L2/L1 Transport IP Remote IP L2/L1 Tunneling layer Remote IP L2/L1 WLAN UE WLAN AN TE WAGPDG IEEE 802.11e IP DiffServ RCF2475

18. Thursday, 12 July 200718 PDG implementation re-using GGSN functionality  GPRS mobile operators can reuse existing infrastructure and functionality for a user accessing from a WLAN UE.  By using this existing standardized reference point, interoperability towards the Gateway GPRS Support Nodes (GGSN) is assured.  Mapping between E2E IP tunnel and GTP tunnel is required. Tunnel Termination Gateway Subset of GGSN functions WLAN UE PDG GTP tunnel end-to-end tunnel Gi / Wi IMS WLAN UE

19. Thursday, 12 July 200719 Implementing PDG by reusing GGSN GGSN P-CSCF PDF IP BS Manager PEF Translation / Mapping function UMTS BS Manager UE Translation / Mapping function WLAN BS Manager IP BS Manager Application Go SIP/SDP Gq PDG TTG IP BS Manager Translation / Mapping function UMTS BS Manager WLAN QoS DiffServ QoS PDP context WLAN AN Translation / Mapping function WLAN BS Manager IP BS Manager

20. Thursday, 12 July 200720 QoS mapping between DiffServ PHBs, UMTS QoS class and EDCA ACs  Costly in term of the required signaling.  Could cause inconsistency in the delivered QoS level to the end user.

21. Thursday, 12 July 200721 Using a stand-alone PDG UE PDG P-CSCF PDF IP BS Manager PEF Translation / Mapping function WLAN BS Manager IP BS Manager Application Go SIP/SDP Gq WLAN QoS DiffServ QoS WLAN AN Translation / Mapping function WLAN BS Manager IP BS Manager

22. Thursday, 12 July 200722 QoS mapping between DiffServ PHBs and EDCA ACs  This mapping scheme has been evaluated in our previous work.

23. Thursday, 12 July 200723 Performance Evaluation of Proposed Framework

24. Thursday, 12 July 200724 QoS Parameters  Delay: The delay (or latency) is the amount of time that it takes for a packet to be transmitted from one point in a network to another point in the network.  Jitter: Jitter is the variation in delay over time experienced by consecutive packets that are part of the same flow.  Throughput: Throughput is the amount of data that can be transferred in a given amount of time.  Packet Loss Rate: Loss rate as a QoS measure determines the maximum number of packets expected to be lost within a specified transfer time.

25. Thursday, 12 July 200725 Scenario 1: Evaluation of WLAN EDCA 802.11e  Reveals the performance of the legacy 802.11 DCF and the 802.11e EDCA.  Using NS-2 Network Simulation. AP Source Nodes Destination Nodes 0 1 2 3 4 5 6 7

26. Thursday, 12 July 200726 Scenario 1: Evaluation of WLAN EDCA 802.11e Legacy DCF 802.11 throughput EDCF 802.11e throughput

27. Thursday, 12 July 200727 Scenario 2: evaluation of WLAN EDCA 802.11e interworking with DiffServ  Simulation was used to evaluate the proposed framework and the mapping between the DiffServ architecture in core network and EDCA 802.11e WLAN. Server End-to-End User Bearer Service IEEE 802.11e Radio Bearer Service Wireline Bearer Service Core Network WLAN UE Access Point RFC 2475 IP DiffServ IP router

28. Thursday, 12 July 200728 Traffic Throughput with CN background load of 20% Traffic Throughput with CN background load of 70%

29. Thursday, 12 July 200729 Lack of QoS impact on the voice throughput. Lack of QoS impact on the video throughput. Lack of QoS impact on the background throughput

30. Thursday, 12 July 200730 Scenario 3: IMS Multimedia Telephony Evaluation on WLAN-3GPP/IMS Interworking End-to-End UE AP1 AP2 WAG UE WAG PDG DiffServ Domain WLAN AN1 WLAN AN2 IPSec Tunnel IMS

31. Thursday, 12 July 200731

32. Thursday, 12 July 200732 Published work This thesis has contributed with the following research papers:  A. Elmangosh, M. Ashibani, F. Ben-Shatwan, “The Interworking between EDCA 802.11e and DiffServ”, IEEE eSCO-Wi 2007 Proceedings of IEEE IPCCC 2007, New Orleans, Louisiana, USA, April 2007.  A. Elmangosh, M. Ashibani, F. Ben-Shatwan, ”Quality of Service Provisioning Issue of Accessing IP Multimedia Subsystem via Wireless LANs”, The first International Conference on New Technologies, Mobility and Security (NTMS) 2007, Paris, France, May 2007.

33. Thursday, 12 July 200733 Conclusion  The (NGN) is foreseen as being an IP-based network that supports a wide variety of services through fixed-mobile environment.  This converged environment requires the support of interworking methods between different QoS technologies, in order to guarantee end-to-end QoS for multimedia sessions in heterogeneous networks.  It is expected that the Differentiated Service module (DiffServ) will become a key QoS assurance mechanism in the upcoming All-IP NGN.  While multimedia services can be delivered to end-users without the IMS framework, however the deploy of IMS will benefits both users and operators

34. Thursday, 12 July 200734 Conclusion  The performance evaluation of our proposed interworking framework between 802.11e WLAN and DiffServ architecture shows the necessity of providing end-to-end QoS in heterogeneous networks.  The results show also that 802.11e EDCA is QoS capable to conform with DiffServ PHBs QoS requirements.  In this work extra functionalities have been introduced to the existing WLAN QSTAs (packet classification and conditioning) in order to support DiffServ architecture. extra cost and delay to the traffic flows. could be easily neglected with the high computation terminals available now-days.

35. Thursday, 12 July 200735 Further Work  In our work we considered only the EDCA access method of the IEEE 802.11e MAC layer because of its expected widely deployment in the near future. Further work need to be done considering the HCCA access method.  The IMS was defined as an access-independent platform, however further work need to be done in this prospect to study the interworking of IMS with other access networks such as Wi-MAX and xDSL.  In this work we depend mainly on the simulation method to evaluate the proposed framework. In further work the same evaluation can be implemented by using the NGN Test-bed currently under constructing at the Higher Institute of Industry.

36. Thursday, 12 July 200736 Thank you