Impacts of LTE on emerging NGN Service Architectures

Transcription

1 ITG-Fachgruppe Systemarchitektur und Traffic Engineering, Jena, 9. Mai 2008 Impacts of LTE on emerging NGN Service Architectures Fabricio Carvalho de Gouveia, M.Sc. Technische Universität Berlin / Fraunhofer Institut FOKUS Next Generation Network Infrastructures (NGNI) Leiter: Prof. Dr. Thomas Magedanz 1

2 Motivation Agenda Evolution of 2G Networks towards NGN IMS on top of Evolved Packet Core Open Issues Design Concept for improvement of performance in the Evolved Packet System Implemented IMS Policy Framework at FOKUS Conclusions and further work 2

3 Motivation to Converged Networks Fixed Networks PSTN ISDN IT DSL Mobile Networks Internet SMS WiFi WiMax WAP Analogue GSM UMA GPRS UMTS HSDPA FTP WWW Portals P2P IM Web2.0 FMC Triple VoIP IPTV Play itv Converged NGN VoD Content Sharing Cable Networks Broadcast Home Networks 3

4 IMS is a broadly Accepted Service Architecture in NGN IMS was initially created to allow the creation of standard and interoperable IP services like PTT, Presence and Instant Messaging in a consistent way. IMS is a generic platform providing IP-based multimedia systems. It provides session and bearer control, policy and charging. IMS is standardized by 3GPP / 3GPP2 and included in TISPAN Architectures LTE (E-UTRAN) has a clear orientation towards efficient packet transmission support, which will add value to IMS on supporting services that require quality and efficiency. 4

5 Circuit Switched to Packet Switched Evolution IP PSTN IP PSTN PSTN IP PSTN IMS IMS Circuit Switched Circuit Switched Packet Switched Circuit Switched Packet Switched Evolved Packet Core Access Access Access Access Network Network Network Network GSM GPRS / EDGE 3G IMS Evolved Packet System

6 IMS Connection to the EPC Other access Types (WLAN, WiMAX) (Outside EPC) S2 S5 S7 PCRF SGi PDN Gateway Rx+ Visited Network P-CSCF Home Domain Mw Cx I-CSCF HSS Mw Cx ISC S-CSCF Mg Application Servers Application Servers MME S11 Serving Gateway Mb MGCF PSTN S1 EPC Mn S1 S1 MGW enodeb enodeb E-UTRAN IMS UE Data path example Reference Points 6

7 IMS to EPC Interfaces Interconnection Interfaces: Rx+: Transports application level session information (e.g. Media/Application Bandwidth for QoS Control) Rx+: At present is called Rx+ for simplification reasons. Combines the Release 6 Rx and Gq, which are applicable towards the CRF and PDF respectively. SGi: Enables IMS Services for users of the Evolved core; SGi: supports any 3GPP and non-3gpp access systems IMS offers equivalent services that are not supported by LTE (Circuit Switched) Therefore it will provide support to CS services during transition to E-UTRAN Voice and other services previously delivered over the CS Core network in UMTS are provided via a PS IP core and IMS 7

8 Open Issues of Interest Macro diversity problem Even though the Evolved Packet Core offers a convergent model for accessing the required services, it does not consider user end-points with the capacity of parallel attachment to multiple access systems (Just one at time, due to power constraints). User end point resource reservation problem multiple access could be resource consuming if no prior information is exchanged with the Packet Core. The decision of connecting to a specific access point is taken by the user end-point, based on some criteria like cost, signal strength and prior knowledge. Resource correlation between the user and the network For a possible second connection, even though the first one has been established, the user end-point continues to consider only those local policies. Thus, it remains agnostic of the load information that is kept by the core, decreasing the possibility of finding a network able to offer the required surplus of resources. 8

9 Non-3GPP access to E-UTRAN Handover Other access Types (WLAN, WiMAX) (Outside EPC) S2 S7 PCRF SGi PDN Gateway Rx+ P-CSCF MME Node manages and stores UE context, and generates temporary identities and allocates them to UEs. Responsible for functions related to subscriber and session management (e.g. authentication, QoS radio negotiation) S5 Problem MME S11 Serving Gateway MME has no influence with non-3gpp accesses S1 S1 S1 EPC QoS and user profiles are always requested in the home domain. enodeb enodeb E-UTRAN UE 9

10 Design Concept Enhancements to the EPC Architecture: Development of a logical QoS Information Function (QIF) keeps track of the resources that are available on the access networks (It will be responsible for collecting information from non-3gpp accesses and forwarding them to the MME); pre-reserves resources on requests in conjunct with the PCRF Is collocated with the PCRF; Extension of the tracking area for transferring information about the networks that can be reachable by the user Triggered by the service signaling, the PCRF filters the requested profile of the user according to the dynamic information received from the QIF. After the policy class is decided for the required service, it is enforced in the PDN GW. 10

11 Registration Scenario 11

12 QoS Provisioning Scenario 12

13 Policy Provisioning Policy functionality in the designed architecture A policy description can be a set of codecs and their usage From this set of codecs the bandwidth and the service class are deduced The PCRF selects a set of policies that could be enforced if the resources permit it The PCRF receives the degree of occupation of the networks from the QIF The user is informed about networks and which resources could be used if the user connects to that network (also for neighbor networks) The network is completely controlled by the operator, thus reducing the risk of possible attacks and the error recovery. 13

14 IMS QoS Reference Model 3GPP Release 6 3GPP Release 7 Policy and Charging Convergence P-CSCF P-CSCF Gm (SIP) Gq (Diameter) PDF Gm (SIP) Rx` (Gq+Rx) (Diameter) PCRF SBLP + Flow Based Charging Control layer Go (COPS) Gx` (Go+Gx) (Diameter) Access layer GGSN (PEP) IP Bearer Service Manager GGSN (PCEF) IP Bearer Service Manager Gz OFCS 14

15 Session is initiated and traffic received but one of the clients breaks the connection without generating the appropiate SIP signaling. Session established Session aborted P-CSCF generates signaling for clients Loss of bearer Event SDP content analysed and parameter mapping P-CSCF PCRF per flow PCEF AAR AAA ASR ASA STR STA Policies applied, no BW parameters. Then assign default 64kbps RAR RAA CCR CCA Default policy for bearer loss is not to wait for a recovery but abort the session Rules Installed in Gateway Client stops sending packages. Inform PCRF Rules are removed, session is no longer authorized 15

16 Session Initiation and QoS limits increased SDP content analysed and parameter mapping Policies applied, no BW parameters. Then assign default 64kbps per flow The Client doesn t make use of SDP extensions to reserve bandwidth. The PCRF will apply a default policy. PCRF assigns default values for BW. And subscribes to events LOSS_OF_BEARER and QoS_CHANGE_EXCEEDING_A UTHORIZATION Session established P-CSCF PCRF PCEF AAR AAA Apply policy. If network has high load then reject this session. If not allow for 10% more of BW RAR RAA CCR CCA New QoS Information, values updated Rules Installed in Gateway Client using more bandwidth than reserved If subscribed to event, inform PCRF 16

17 PCRF Performance Results Delay for Op 1-4 (values expressed in Median and Standard Deviation in microseconds) Operations under test 17

18 PCEF Performance Results Testing System Model Test for delays in operations of Gx interface (values expressed in milliseconds) 18

19 Application of PCC in the EPS The Evolved Packet System applies the PCC framework as defined in TS for QoS policy and charging control. The service level QoS parameters consist of: QoS Class Identifier (QCI) QCI is a scalar that represents the QoS characteristics that the EPS is expected to provide for the Service Data Flow (SDF) authorised Guaranteed and Maximum Bit Rate values for uplink and downlink (GBR, MBR) 19

20 Summary The EPS work in 3GPP is defining the evolution beyond Rel-7. The presented enhancement to the SAE architecture have the objective to optimize the QoS provision in a single operator scenario. Therefore a new logical component QIF (QoS Information Function) was proposed. It is able to register the load of the access networks. This function receives information about the various networks and provide filters for selecting the ones that have enough resources for the user required services. The Mobility Management Entity (MME) has knowledge of the user location by using a Tracking Area, and will receive information from the QIF in the case of non-3gpp accesses. The QIF provides intelligence in the visited network, providing network controlled handover decisions. PCEF supports event subscription from the PCRF for reporting specific bearer level events. Performance results of the PCEF for installing/deleting/modifying rules were carryed, showing the feasibility of the prototype for EPC application. 20

21 Thank You! Fabricio Carvalho de Gouveia, M.Sc. Technische Universität Berlin / Fraunhofer Institut FOKUS 21

22 T. Magedanz (TU Berlin / Fraunhofer FOKUS) Open NGN Fraunhofer FOKUS National R&D Projects European R&D Projects mhealth mgov mxxx. weitere weitere Other Apps Applications Web services OSA/Parlay Playground Parlay IMS AAA SIP 3Gb Service Platforms Other weitere Roaming & Middleware platforms VoIP SIP IpTel Lab UMTS GSM / WLAN DVB- FDD/ weitere Other GPRS a/b/x S/T TDD Netws 3Gb Network Technologies Engineering Tools,Conformance Testing, Measurments, and Managem ment Open NGN Test & Development Center Testbeds are considered key for sustainable research Testbed focus is on IP and service platform layers Foundation for industrial and academic projects Applications development support Applications validation Service Platform prototyping Infrastructure component testing Network technologies integration 22

23 T. Magedanz (TU Berlin / Fraunhofer FOKUS) IMS Testbeds as R&D FOKUS In November 2004 after 2 years of development sponsored by BMBF and FOKUS the FOKUS Open IMS Playground has been officially opened Technical foundation was the expertise and available software in the fields of Open Source SIP Express Router (SER) und FOKUS OSA/Parlay Gateway (OCS) The Open IMS Playground is the globally pioneering open IMS Testbed und contains FOKUS own developed and industry partner IMS products In November 2006 the FOKUS Open Source IMS (OSIMS) Core System - the core of the IMS playground - has been offiically released to the general public via the BerliOS Download site OSIMS allows industry and academic institutions to setup own testbeds (with or without FOKUS support and components) Since then OSIMS has been downloaded many thousand times from all over the world 23

24 T. Magedanz (TU Berlin / Fraunhofer FOKUS) FOKUS Open IMS Playground and Core SIP AS Parlay X GW XDM S Presence Sh Consulting Note: This is not a complete e Partner List! I-CSCF Cx Mw Mw P-CSCF Gm Cx Mw S-CSCF ISC Mw Mw M edia Server Media GW Signalling GW Legacy networks GSM, PSTN Charging Testing Tools IMS Clients 24

25 T. Magedanz (TU Berlin / Fraunhofer FOKUS) Export of Testbed Technologies for R&D Projects Remote Testbeds Examples: Uni Cape Town, TU Vienna, WIT Ireland 1 Free Download Platform NGN Open Testbeds NGN Open Testbeds NGN Open Testbeds Cooperation FOKUS SOA / MIL Components + Partner NGN Components Operators 2 & Vendors Industry Testbeds Industry Testbeds Industry Testbeds IMS Testbed IMS Testbed IMS Testbed IMS Testbed Examples: South Africa, Korea, Indonesia, Japan, Examples: O2, T-Com, Arcor, NSN, Ericsson 25

26 T. Magedanz (TU Berlin / Fraunhofer FOKUS) IMS Testbeds as R&D FOKUS (cont.) In September 2007 the FOKUS Open SOA Telco Playground has been officially opened to address R&D in the IMS application layer Extends the R&D activities above the IMS core layer in face of emerging IMS enablers and their orchestration (SCIM, service brokering), SOA principles and Web 2.0 APIs Focus is on service cretaion / service orchestration, service brokering and execution, service provisiong, SOA based NGN services management, etc In September 2007 the Media Interoperability Laboratory (MIL) has been officially opened based on the existing activities in the fields of Triple Play, Quad Play, IPTV and home enetrtainment Extends the R&D activities in the field of emerging IPTV, interactive TV, converged services (integration communications and entertainment services) First IMS-based prototype has been shown at IFA 2007 Fair, Berlin 26

27 T. Magedanz (TU Berlin / Fraunhofer FOKUS) IMS-based IPTV / Media Interop Lab NextGenMedia Clients NextGenMedia Enablers NextGenMedia Discovery & Selection (EPG & BCG) NextGenMedia Media Control & Adaptation NextGenMedia Media Reference Management (CRID) NextGenMedia Personalization (Rating & Recommedation) User side Content Creation, Management, and Retrieval NextGenMedia Storage, Distribution, and Delivery New R&D Issues 27

28 T. Magedanz (TU Berlin / Fraunhofer FOKUS) Towards SOA over IMS A lot of work in the Open IMS playground has been performed in the context of IMS applications prototyping and IMS SDP integration Today the new buzzword SOA (Service Oriented Architecture) is used to describe a service delivery platform, which features reusability of service components and service orchestration Therefore, we have established the Open SOA Telco Playground on top of the Open IMS Playground in summer 2007 to reflect our activities in this domain See 28

29 T. Magedanz (TU Berlin / Fraunhofer FOKUS) FOKUS work in the context of SOA Telco Based on the long term practical experiences in international projects performed for various vendors and network operators, FOKUS is currently concentrating on the following areas of work within a SOA-based Telecommunications Environment: Integration of telecommunications and Web 2.0 services under exploitation of SOA principles, focusing on both end system based as well as server based service orchestration. This leads to a very flexible service implementation infrastructure for Development of advanced service brokers for IMS (= SIP-based) services and non IMS (= HTTP-based) services. Development and extension of SOA-based IMS application servers. Prototyping of community based SOA services on top of IMS and legacy networks based on Parlay X and OMA PEEM Design and Development of an extensible Management solution for SOA-based NGN/IMS environments, including service provisioning systems for SOA-based IMS environments and monitoring and fault management systems Development of SOA-based Autonomic Communications Infrastructures (as part of the Composite Services Management Workgroup of the Autonomic Communications Forum (ACF) 29

30 T. Magedanz (TU Berlin / Fraunhofer FOKUS) A Sample SOA-based NGN Architecture 30

31 T. Magedanz (TU Berlin / Fraunhofer FOKUS) FOKUS SOA Telco Components Service Broker Governance of service requests References to applicable access and usage policies at PEEM Triggers OSS/BSS for new service deployment Service Chaining / Service Interaction Policy Evaluation, Enforcement and Management (PEEM) Policies for service access authorization and definition of enabler capabilities SCIM functionality for service orchestration on SIP level (ISC interface) Interacts with Service Broker as policy repository Web 2.0 Enabler Two-way perspective: Inclusion of Web2.0 enablers into Telco services for mobile/iptv customers Exposure of Telco network capabilities to be included into Web2.0 mashups 31

32 T. Magedanz (TU Berlin / Fraunhofer FOKUS) FOKUS SOA Telco Components Service Registry Extended UDDI Resource Inventory Network element and functionality inventory for OSS / BSS orchestration Service Creation Anchor point for MDE-based service creation tools 32

33 T. Magedanz (TU Berlin / Fraunhofer FOKUS) If you want more Mark your Calendars! 4th International FOKUS IMS Workshop Berlin, Germany, November 6-7, Featuring: IMS Starters Tutorial, Open Source Starters Tutorial Many Operator Talks Several interactive Workshops Vendor Exposition IMS Playground Visits and IMS Service Demonstrations FOKUS SOA Telco and Media Interoperability Lab Tours 33

34 Useful References Third Generation Partnership Project, Telecoms and Internet Converged Services and Protocols for Advanced Networks, Richard Good, Fabricio Carvalho de Gouveia, Shengyao Chen, Neco Ventura and Thomas Magedanz, "Critical Issues for QoS Management and Provisioning in the IP Multimedia Subsystem", Journal of Network and Systems Management (JNSM), Springer Netherlands, ISSN (Print) (Online), DOI /s , April Gouveia, Fabricio C., Magedanz, Thomas, QUALITY OF SERVICE IN TELECOMMUNICATION NETWORKS, from Encyclopedia of Life Support Systems (EOLSS), Developed under the Auspices of the UNESCO, Eolss Publishers, Oxford,UK, [ [Retrieved August, 2006] Fraunhofer FOKUS Open IMS Playground, Fraunhofer FOKUS Open Source IMS Core Project, T. Magedanz, F. Gouveia: "IMS - The IP Multimedia System as NGN Service Delivery Platform", e&i - elektrotechnik und informationstechnik, Themenschwerpunkt: Vermittlungstechnik, e&i 123, Heft 7-8, pp ,.August, 2006, ISSN: X EIEIEE 123 (7-8) , a1-a44 (2006) Corici, M. I.; Gouveia, F. C.; Magedanz, T. A Network Controlled QoS Model over the 3GPP System Architecture Evolution, Second Australian Conference on Wireless Broadband and Ultra Wideband Communications - AusWireless 2007, Crowne Plaza Hotel, Sydney, Australia, August

35 Useful References K. Knüttel, T.Magedanz, D. Witszek: THE IMS FOKUS AN OPEN TESTBED FOR NEXT GENERATION NETWORK MULTIMEDIA SERVICES, 1st Int. IFIP Conference on Testbeds and Research Infrastructures for the DEvelopment of NeTworks and COMmunities (Tridentcom), Trento, Italy, February 23-25, 2005, Proceedings pp. 2 11, IBSN x, IEEE Computer Society Press, Los Alamitos, California, M. Sher, F. C. Gouveia, T. Magedanz, IP Multimedia Subsystem (IMS) for Emerging All-IP Networks, Encyclopedia of Internet Technologies and Applications, Mário Freire & Manuela Pereira (editors), Idea Group Inc. (pub.), D. Vingarzan, P. Weik, T. Magedanz: Development of an open source IMS core for emerging IMS testbeds, Special Issue on IMS, Journal on Mobile Multimedia (JMM), Vol.3 No.2, Rinton Press, Princeton, USA, 2007, P. Weik, D. Vingazan, T. Magedanz: Towards an open source IMS core system enabling rapid prototyping of NGN services, 3rd INTERNATIONAL WORKSHOP ON NEXT GENERATION NETWORKING MIDDLEWARE (NGNM06), p.23-29, ISBN: , Coimbra, Portugal, May 19, 2006, F. Gouveia, J. Floroiu, T. Magedanz: Seamless Service Access for Mobile SIP-based Applications and IMS Services on Top of Different Access Networks, 6thInternational IEEE Workshop on Applications and Services in Wireless Networks, by Fraunhofer FOKUS, ISBN , pp , Berlin, Germany, May 29-31, 2006, 35