HSN2005 BcN 네트워킹구조모델 2005. 1. 27. 박홍식 BcN 엔지니어링연구센터 (ICU) hspark@icu.ac.kr
2 Contents Introduction BcN services and capabilities BcN functional architecture BcN physical architecture Service architecture QoS architecture Evolution of legacy networks toward BcN Concluding remarks
3 BcN 정의 BcN 음성 데이터, 유 무선, 통신 방송융합형멀티미디어서비스를언제어디서나편리하게이용할수있는서비스통합망 다양한서비스를용이하게개발 제공할수있는개방형플랫폼 (Open API) 기반통신망 통신망, 단말에구애받지않고다양한서비스를끊김없이이용할수있는유비쿼터스서비스환경을지원하는통신망 Requirements 품질보장 (QoS), 보안 (Security), IPv6, Open API
4 BcN 융합서비스 Converged service 1st Phase 2nd Phase 3rd Phase Voice-data Wired-wireless - VOIP - High-speed Internet - WLAN - Video phone - VOD - Portable Internet - 4G, FTTH broadband converged service Comm-broadcast - DMB - T-commerce - T-gov - High-quality VoD - Bidirectional DMB - HD-grade QoSguaranteed multimedia service
5 NGN 정의 A packet-based network able to provide telecommunication services and able to make use of multiple broadband, QoS-enabled transport technologies In NGN, service-related functions are independent from underlying transport-related technologies Offers unrestricted access by users to different service providers Supports generalized mobility which will allow consistent and ubiquitous provision of services to users
6 NGN 특징 -1 Packet-based transfer Separation of control functions among bearer capabilities, call/session, and application/ service Decoupling of service provision from network and provision of open interfaces Support for a wide range of services, applications and mechanisms Including real time/ streaming/ non-real time services and multi-media Broadband capabilities with end-to-end QoS and transparency Interworking with legacy networks via open interfaces Generalized mobility
7 NGN 특징 -2 Unrestricted access by users to different service providers A variety of identification schemes for routing in IP networks Unified service characteristics for the same service as perceived by the user Converged services between Fixed/Mobile Compliant with all regulatory requirements For example, concerning emergency communications and security/privacy, etc.
8 NGN Architecture Service stratum Application functions Customer DB functions Service and control functions Customer functions UNI Network entry functions Access Access Transport Transport functions functions Transport stratum Transport adaptation functions Network entry functions Core Core Transport Transport functions functions Media handling functions Gateway functions NNI Other Other networks networks Control Media Note: Charging and billing functions and Management functions are applied to both Service and Transport strata
9 NGN Functional Entities Based on IMS Applications Legacy Terminals IP Connectivity Access Network And related functionality GW User Profiles Network Attachment Functionality NASS Other Multimedia Components Streaming Services (RTSP based) PSTN / ISDN Emulation (SIP-I based) Resource and Admission Control Functionality RACS IP Multimedia Component ( IMS) (SIP based) Other Networks Customer Networks NGN Terminals Access Transport Network Core transport Network
10 BcN Services - 1 Session Controller-based services Real-time conversational voice services Point-to-point interactive multimedia services, including interactive real-time voice, video and other media (videotelephony, whiteboarding, etc.) VPN services Collaborative interactive communication services Push to talk over NGN (PoN) Content delivery services Sensor network services Presence and general notification services: display of peers that a user can contact, their current status, and any service-related notifications Instant messaging (IM) : A type of communications service that enables the user to create a kind of private chat room Existing PSTN/ISDN services; PSTN/ISDN emulation and simulation Session controller-based Internet services Session controller-based access services to Internet Service Providers Hosted and transit services for enterprises (IP Centrex, etc.) Group messaging Instant messaging and deferred messaging
11 BcN Services - 2 Non Session Controller-based Services Data communication services, such as data file transfer, fax, electronic mailbox and web browsing Data retrieval applications, such as tele-software Push services Information services, such as cinema ticket information, motorway traffic status, advanced push services, etc. Online applications (online sales for consumers, e-commerce, online procurement for commercials, ) Speech-enabled services Remote control/tele-action services, such as home applications control, telemetry, alarms etc. Messaging services such as SMS, MMS, etc. Broadcast/Multicast Services Telematics Services
12 BcN Capabilities Basic network capabilities Switching and routing, routing/address resolution, IP bearer control, client/server address management, client/server registration, charging, interworking, etc. Mobility Service, terminal, user mobility Identification and authentication Location management Presence Capability to collect, collate, track, and provide presence information Support services such as communication services (IM, MMS, etc.) Group management (CUG/VPN) Session control Service subscription (registration) management User and terminal profile management Resource and QoS management Security support Service creation and customization
13 BcN Functional Architecture Application Function Application Server Function Application Gateway Function Session & call control Network Access Attachment Functions Access RACF Session Control Proxy Function Resource and Admission Control Function A-TRCF Session Control Function M-PDF MRCF Resource Meditation Core RACF AGCF C-TRCF PGCF MGCF I-PDF I-BCF Other Networks Transport Terminal Function Access Relay Function Network Access Control Function Network Access Process Function Mobility Support Function Media Resource Processing Function Traffic Measurement Function Transport Resource & Enforcement Function Media Resource Processing Function Traffic Measurement Function Transport Resource & Enforcement Function PGF AMGF Access Packet Transport Function Core Packet Transport Function TMGF
14 Transport Functional Entities - 1 Packet Transport Function Transfers user /control/ and management information transparently Packet Gateway Function Packet interworking between multi-ngn domains Media conversion under the control of PGCF Network Access Process Function (TAPF) For media-related processing, such as firewall functions, NAPT functions under the control of NACF (Network Access Control Function) Access Media Gateway Function Media conversion between media streams from the packet-based transport in the NGN and bearer channels on the analogue lines or ISDN accesses
15 Transport Functional Entities - 2 Access Relay Function (ARF) Inserts some pre-configuration information i.e. location information in network access requests and converts them into network access requests The ARF proxies configuration requests from end-user equipments to CMPF, such as request for update of software Mobility Support Function (MSF) Provides user and terminal mobility where applicable Trunk Media Gateway Function (TMGF) Provides media conversion between media streams from a packet-based transport in the NGN and bearer channels on the trunk lines from the circuit switched network
16 Transport Functional Entities - 3 Media Resource Process Function (MRPF) Delivers contents (videos, documents, Web pages...) Allocates specialized resource (such as announcement server, notification tone, and voice recognition resource, voice menu and conference resource etc.) Provides media mixing functions under the control of the MRCF Signalling Gateway Function (SGF) Responsibility for signalling transport interworking between NGN and existing networks such as PSTN, ISDN, IN network, and SS7 Traffic Measurement Function (TMF) Generates traffic and statistic data for management and accounting purposes Transport Policy Enforcement Function (TPEF) Responsibility for transport processing functions under the control of TRCF such as link negotiation/establish, packet forwarding and QoS procedures (packet marking, resource establishment and release, resource reservation, queuing management ) etc.
17 Transport Functional Entities - 4 Transport Resource/ Policy Control Function (TRPCF) Manages and controls the policy of transport layer handles the collection of network resource and maintenance the network resource status information; interacts with NAPF and TPEF for transport resource allocation and control, such as port, link, bandwidth and access list etc. Transport Authentication and Authorisation Function (TAAF) Provides authentication and authorization at the transport layer Network Access Control Function (NACF) Controls firewall policy, network address translation policy, security policy Address allocation, and session admission according to user profile and resources status
18 Session and Call Control Functional Entities - 1 Session Control Function (SCF) Handles functionality related to session logical control, session setup, modification and teardown User Profile Database Function (UPDF) Storage of user profile and subscriber-related location data and presence Service Authentication and Authorization Function (SAAF) Provides authentication and authorization at the service layer ensures that the end-user has valid utilization rights for the requested service performs policy controls at the service level using policy rules contained in a User Profile Data Base. Register Function (REGF) Processes the request from the user (and the terminal) for registration
19 Session and Call Control Functional Entities - 2 Media Resource Control Function (MRCF) Allocates resources which are needed for services such as streaming, announcements, IVR (Interactive Voice Response) support Media Gateway Control Function (MGCF) Interworks with PSTN/ISDN Controls AMGF to accommodate existing subscribers Generates charging record CDRs
20 Session and Call Control Functional Entities - 3 Packet Gateway Control Function (PGCF) Controls PGF to interwork with other packet-based network supports network topology hiding generates charging record CDRs Location Service Function (LSF) Exchanging the user's location information with other domains Gains inter-domain users' location information from UDBF Accepts and processes the inquiring request from SCF Conveys PGCF information if called party is located in the outer-domain Session Control Proxy Function (SCPF) proxies or relays session packets to SCF according to the service requirements interacts with resource control when no explicit relative signalling (i.e. QoS Signalling) is available
21 Application Functional Entities - 1 Application Server Function (ASF) Provides service control for session based services by interacting with the SCF Provides services to the NGN terminal function Application specific authorization and authentication Application Service Gateway Function (AGWF) Serves as interworking entity between the SCF and APF Provides open interface (etc. API) towards the third-party application service providers
22 Application Functional Entities - 2 Charging and billing Functional entities Provides accounting data to the network operator regarding the utilization of resources Supports the collection of data for later processing (offline charging) as well as near-real time interactions with applications such as for pre-paid services (online charging) Billing Domain and Backend Systems Account Management Function Charging Collection Function Online Charging Function Offline Charging Charging Trigger Function NGN Functional Entity Rating Function Online Charging
23 BcN Physical Architecture - Example Application Community Collaboration Contents Commerce Service stratum Service/ Network Control Platform QoS/Traffic Control NW defense HGW management Multi-point video-conference Presence SIP Certification Authority Single Sign-On Server RADIUS Accounting Home Agent Access Independent (Core Transport) Network PSTN GW Visual System HE Core Node Multi-layer Service Edge Service Node NNI GW Other Network Transport stratum Access Dependent Network RAN GW MSC RMC BS DSLAM ADSL modem V-OLT V-ONU Distribution Function OLT ONU WDM ONU Wireline Access MC MC MC MC HE: Head end MSC: Mobile Switching Center RMC: Radio Media Converter BS: Base Station DSLAM: Digital Subscriber Access Module OLT: Optical Line Terminal ONU: Optical Network Unit MC: Media Converter User Network Business User Ubiquitous Network UNI HGW Mass User
24 Service Architecture Requirements Distributed control To adapt to the distributed processing nature of IP network, eliminate the structural defects of SS7 signalling architecture, and support the location transparency of distributed computing Open control The network control interface should be open to support the service creation, service update, and service logic by third parties Separate the service provision process from network operation Encourage the competitive environment of NGN to speed up the provision of diversified value added services Support the services of converged network generate converged voice/data services that are flexible and easy to use, so as to tap the technical potential and market value of NGN Provide enhanced security and protection as basic requirement of an open architecture. protect the network infrastructure by ensuring the trustworthiness of the service provider
25 Service Architecture Third party not trusted Third party trusted Independent of the network operator SCE SCE Applications (3 rd Parties) DPE Location transparency Security interface Server 1 Server 2 Server n 厖 Application Application Server Server Platform Platform OMA Service Environment Network transparency Protocol interface Interface 1 Protocol interface Interface 2 Protocol interface n Protocol transparency NGN BcN PSTN GSM /CDMA Softswitch Independent of the manufacturer Phone Set Fax machine Mobile Phone PDA PC Intelligent Terminal Service merge
26 Service Architecture Components Third party trusted Network providers themselves, subordinate organizations or partners Third party not trusted Independent service providers Access must be authenticated, controlled and filtered Service Creation Environment (SCE) Creates instant services Application server platform Serves as a server group Each category of servers corresponds to one type of basic services, and executes corresponding service actions under the control of a third party service logic Protocol adaptation interface Through which, a service server maps the execution action into the control protocol process of the network
End-to-end QoS Architecture 27
28 Resource and Admission Control Subsystem Functional Architecture Application Functions Network Access Attachment Functions SCPF SCF IBCF I1 Gq Id Access RACF A-TRCF X1 M-PDF Resource Mediation X2 C-TRCF Core RACF X3 I-PDF X4 Other networks C1 C2 C3 Go G2 G3 CPN R-BGF ANF Access Transport ENF A-BGF Core Transport I-BGF R-BGF - Residential Border Gateway Function CPN - Customer Premises Network ANF - Access Node Function ENF - Edge Node Function SCPF - Session Control Proxy Function SCF - Session Control Function IBCF - Interconnection Border Control Function M-PDF - Mediation Policy Decision Function I-PDF -Interconnection Policy Decision Function A-TRCF -Transport Resource Control Function over access network C-TRCF -Transport Resource Control Function over core networks A-BGF - Access Border Gateway Function I-BGF - Interconnection Border Gateway Function
29 RACS Components Policy Decision Function Makes policy decisions based on request information in terms of the network resource and admission control Consults the TRCF for resource availability to determine whether to admit a service request Transport Resource Control Function Is a collective of QoS routing, resource reservation and admission control functionalities which are distributed over network domains Collects and maintains the network topology and resource status information Controls the resource reservation in a network
30 PSTN Evolution to BcN - 1 Prior replacement of LE and access elements Phase 0 Phase 1 Phase 2
31 PSTN Evolution to BcN - 2 Prior replacement of TE Phase 0 Phase 1 Phase 0
32 PSTN Evolution to BcN - 3 Accommodating mobile networks together in phase1 Mobile Signaling Network MGC MGC BICC/SIP SIP-T ATM /IP H.248 H.248 EO PSTN TO MG TO PSTN EO Convergence of voice and data networks Transport independent signaling mechanisms BICC is important technology in wireless and TDM network Backbone transport packetized Network Edge Node IP Network Network Edge Node MG
33 PSTN Evolution to BcN - 4 Deployment of an overlay NGN to PSTN
34 Internet Evolution to BcN Best effort Internet QoS-enabled Internet Customer manageable IP network
35 QoS Supports in Internet RSVP Signaling protocol supporting IntServ along the path to set up per-flow QoS Mechanism for configuring traffic handling mechanisms in network devices for per-flow-based traffic DiffServ Traffic handling mechanism for aggregate traffic to overcome scalability problems of per-flow QoS management DSCP, packet classification, PHB, packet marking, packet policing MPLS Mechanism for engineering network traffic patterns that is not subject to the limitations of different routing protocols, transport layers, addressing Increase the efficiency of data throughput by optimizing packet processing overhead
36 QoS Building Blocks Control Plane Management Plane Admission control QoS routing Resource reservation SLS monitoring Data Plane Policy management Traffic policing Traffic classification Packet marking Congestion avoidance Queueing & scheduling Buffer management Traffic shaping/ dropping Service restoration SLA
37 QoS Supports in Enterprise Networks WAN QoS mechanisms DiffServ MPLS LAN QoS mechanisms Switched full-duplex Ethernet (L2 switch) IEEE 802.1D user priorities Subnet bandwidth manager signaling protocol RSVP E2E LAN-WAN interworking IntServ over DiffServ Service and policy infrastructure SLS, DiffServ implementations CAC for VOIP
38 QoS Support in Enterprise Networks Signaling Internet Admission Policies VoTDM QCS Billing QNS BR GW VoIP GK CR CR H.323 VoIP AR ER CBQ DiffServ WFQ CR CR MPLS with RSVP-TE or CR-LDP ER Host Enterprise premises LAN IP data 802.1D/Q RSVP-E2E H.323 DiffServ and priority Queue Service provider IP WAN LAN QoS LAN to WAN interwoking WAN QoS
39 Definition of Manageable IP Service A customer can choose the end users which include human, terminal equipments, and applications The customer can configure their own networking services and network configurations (e.g. virtual private network) with relevant network resources provided by the network providers The customer can choose some control and management functions over their own network
40 Levels of Manageability Levels Descriptions Features Remarks 0 No Management 1 2 Overall Network Resource Management Group level Resource Management No monitoring, No Resource Control Overall monitoring, No Resource Control Group level Resource Monitoring and Control No mechanism to detect network fault and congestion. No mechanism to control network resources Notify overall network fault and resource status by network provider No resource control by the customer Notify group level network fault and resource status by network provider Manage the group level resources by the customer 3 Individual Resource Management Individual level Resource Monitoring and Control Notify individual network fault and resource status for end-to-end connectivity Manage the end-to-end resources by the customer
41 Mobile Network Evolution to BcN - 1 R99 (Dec 1999)
42 Mobile Network Evolution to BcN - 2 R4 (March 2001) Bearer independent CS CN
43 Mobile Network Evolution to BcN - 3 R5: Introduction of IMS on top of PS Domain IMS BTS BSC HLR HSS AS services & applications AS BSC BTS CSCF GERAN GGSN HLR HSS MAP MGCF MGW SIP SGSN RAN RNC UE UTRAN Application Server Base Station Controller Base Transceiver Station Call Session Control Function GSM/EDGE RAN Gateway GPRS Support Node Home Location Register Home Subscriber Service Mobile Application Part Media Gateway Control Function Media Gateway Session Initiation Protocol Serving GPRS Support Node Radio Access Network Radio Network Controller User Equipment UMTS Terrestrial RAN UE GERAN NodeB RNC UTRAN Access Network SIP MAP SIP Diameter SIP CSCF MGCF H.248 MGW SIP SGSN GGSN Packet Switched (PS) domain Core Network ISUP Internet PSTN/ISDN Interworked Network
44 IMS (IP Multimedia Subsystem) IMS is a multimedia control/call control platform in the PS domain IMS brings CS functionality to PS, e.g. by offering QoS and enhanced charging capabilities, to enable real-time services IMS introduces new IP based services to the mobile world built on Single sign-on (authentication) Access charging, service charging and content charging IMS introduces enhanced network services like Presence Messaging Conferencing
45 Principles of IMS SIP as the single control protocol for all IP multimedia services Use IPv6 IPv4 in the standard became recently a topic Home Control The home network controls the services for a roaming user Access Independence IMS is designed to be independent of the underlying IP connectivity network Binding between control plane (SIP Dialogue) and user plane (Media Session) in particular for QoS and charging
Mobile Network Evolution to BcN - 4 46
47 Concluding Remarks BcN 은 why 이슈가아닌 when and how 의이슈 BcN 은 End-to-end QoS support General mobility support Customer manageable IP Open API 등을통해새로운비즈니스모델창출, IT 839 신성장동력산업의고부가가치화및국제경쟁력강화에기여해야함 기존망의 BcN 진화전략역시서비스연속성보장, CAPEX/ OPEX 절감, BcN 서비스조기도입측면에서중요 BcN features Scalable, flexible, manageable, open Broadband, packet-based