6.1. Transition to NGN: First wave

1. 6. Next Generation Networks6.1. Transition to NGN6.2. Key drivers of NGN development 6.3. Evolution of networks’ architecture to NGN 6.4. NGN architecture6.5. Main NGN protocols and building blocks

2. 6.1. Transition to NGN: First wave • Growth of Internet and other IP-based networks with their requirements for bandwidth and capacity has driven rapid innovation in telecommunication access and transport networks Examples: – leveraging copper wire “last-mile” networks through digital subscriber line (“DSL”) technologies – re-architecturing of cable networks to support IP services – advances in optical networking technologies (e.g. PON)

3. Convergence of Telephony World and Internet World

4. Transition to NGN: Second wave • Ongoing trend towards integration & interoperability of IP- based and PSTN network services and applications • Emergence of differentiated Quality of Service IP-based services • Managed end-to-end performance needed for new applications requiring real-time traffic (e.g., video, voice) • New network management, QoS, traffic engineering, pricing & accounting models

5. Transition to NGN: Third wave • Evolution of current PSTN, mobile, wireless and IP-based networks to unified Next Generation Networks providing both Internet and carrier-grade telecommunications networks and services offerings with QoS • Transition to Third wave: Ubiquitous & Pervasive Networks – anybody, anytime, anywhere • Global Information Infrastructure (GII) – ITU, 1995 • EII ETSI Project (1995) • ETSI – 3GPP (1998) • 3GPP activity (FMC and IMS development) • TISPAN Project (ETSI, 2003) TISPAN - Telecoms & Internet converged Services & Protocols for Advanced Networks • ITU NGN 2004 Project • Y.1xx ITU-T – SG 13 “NGN – Architecture, Evolution and Convergence”

6. Transition to NGN: Third wave One unified network for everything Today Tomorrow Internet Telephone network IP-Network Mobile radio network • Multimedia Access - Advantages: • easy to handle • reliable • mobile

7. The Unified NetworkThe Vision Situation Today Target Solution Voice Fix and Mobile The Unified Multi Service Network FR IP ... ATM

8. Pure technology/standardization matter: How different data services can transport over a unique data backbone The Unified NetworkThe Data Migration Voice The Unified Multi Service Network FR IP ... ATM

9. Somewhat more complex - From circuit switched to packet switched - Voice switches need to disappear in the long term The Unified NetworkThe Voice Migration Voice The Unified Multi Service Network FR IP ... A new network concept supporting voice in a packetized environment is required The Next Generation Network ATM

10. ITU-T definition of NGN (Y.2001, Feb 2004) “A Next Generation Network (NGN) is a packet-based network able to provide services including Telecommunications Services and able to make use ofmultiple broadband, QoS-enabled transport technologiesand in whichservice-related functions are independent from underlying transport-related technologies. It offers unrestricted access by users to different service providers. It supports generalized mobility which will allow consistent and ubiquitous provision of services to users.” One of the primary goals of NGN is to provide a common, unified, and flexible service architecture that can support multiple types of services over multiple types of transport networks.

11. NGN is the public packet-based network with the following main features: • Layered architecture • Open interfaces between the layers and all other networks • Seamless control of multiple transport technologies • Centralized intelligence

12. NGN Characteristics The NGN is characterized by the following fundamental aspects: • Packet-based transfer in the core NGN network • Support for a wide range of services, applications and mechanisms (including real time/ streaming/ non-real time services and multi-media) • Independence of service-related functions from underlying transport technologies • Separation of control functions among bearer capabilities, call/session, and applications/services • Broadband capabilities with required end-to-end QoS • Interworking with legacy networks via open interfaces • Generalized mobility • Unrestricted access by users to different service providers • Services convergence between Fixed/Mobile • Compliance with all Regulatory requirements, for example concerning emergency communications, security/privacy, etc.

13. 6.2. Key drivers of NGN development • Short Term objective:Create new revenue possibilities • Removal of boundaries between voice and data opens the way to new kind of services • Can be realized relatively quickly with limited investments • Long Term objective:Realize cost savings • Simpler network • More efficient network • Cheaper network components • Full benefit only realized when all separate networks have fully migrated towards to the target solution

14. Driven by Revenue Increase Possibilities Driven by Cost Reduction Possibilities Key drivers: technologies and services Next Generation Network

15. NGN key drivers: From IP Technology to User and Application Centric • User demands • easiness to use and personalization of services • seamless service regardless of the access technology • a “beautiful garden” offering valuable services with security • openness to the entire Community • Operator challenges need to be addressed • need to manage complexity to deliver simplicity • platform for convergence of services and technologies • support of different device and access technologies • revenue opportunities by mobility and nomadicity, worldwide use • support migration from existing technologies

16. NGN services

17. NGN Services • Voice Telephony – NGN will likely need to support various existing voice telephony services (e.g., Call Waiting, Call Forwarding, 3-Way Calling, various IN features, various Centrex features and etc.). • Data Services – Allows for the real-time establishment of connectivity between endpoints, along with various value-added features • Multimedia Services – Allows multiple parties to interact using voice, video, and/or data. • Virtual Private Networks (VPNs) – Voice VPNs improve the interlocation networking capabilities of businesses by allowing large, geographically dispersed organizations to combine their existing private networks with portions of the PSTN, thus providing subscribers with uniform dialing capabilities. .

18. NGN Services • Public Network Computing (PNC) – Provides public network-based computing services for businesses and consumers. • Unified Messaging – Supports the delivery of voice mail, email, fax mail, and pages through common interfaces. • Information Brokering – Involves advertising, finding, and providing information to match consumers with providers. • E-Commerce – Allows consumers to purchase goods and services electronically over the network. Home banking and home shopping fall into this category of services. This also includes business-to-business applications

19. NGN Services • Call Center/Web Contact Services – A subscriber could place a call to a call/Web contact center agent by clicking on a Web page. • Interactive gaming – Offers consumers a way to meet online and establish interactive gaming sessions (e.g., video games). • Distributed Virtual Reality – Refers to technologically generated representations of real world events, people, places, experiences, etc., • Home Manager – With the advent of in-home networking and intelligent appliances, these services could monitor and control home security systems, energy systems, home entertainment systems, and other home appliances.

20. Applications • VoIP • Web Browsing • Chat • Instant Messaging • WAP Browsing • Multimedia Messaging • VoD – Movies/Gaming/News/Sports/Training • Video Telephony • Video Broadcasting • Video Conferencing • Video Collaboration • IP PBX/Centrex • Email

21. Web, email,chat, etc. Gaming NGN Video on Demand(VoD) Conversational real-time communication Smart Home High Definition TV(HDTV) NGN Today: Facing the Multi-Application/Multi-Access Challenge

22. 6.3. Evolution of networks’ architecture to NGN • The unified network will use packet-based technology as the common transport mechanism • Data is the fastest growing segment due to • Success of Internet • Growing use of E-mail • Growing data traffic between business users • Data should be handled in the most efficient way • Packet technology is the best way to transport data • Packet technology is only technology that allows simultaneous delivery of different information streams towards one and the same end-point on one single connection

23. Evolution of network architecture • Traditional telephony - Circuit switch based PSTN

24. Evolution of network architecture •Circuit Switched PSTN + Packet Switched IP network (VoIP Gateway) SG – Signaling gateway MGC – Media gateway controller MG – Media gateway

25. Evolution of network architecture • Completely IP-oriented network

26. Convergence of network technologies and media Nx64 kbps

27. 6.4. NGN architecture Management System Management Servers Application Servers Applications Softswitches Signaling gateways Control Packet Network Core MediaGateway Mobile MediaGateway PSTN Edge Broadband Access UTRAN CO DSL WLL Cable Mobile Users Enterprise Customers Remote Office/SOHO ResidentialUsers

28. NGN architecture - NGN functional model Application/Management Part Application Servers Management Servers Open Services Interfaces/API … Session Part (Call control) Softswitches Media Gateway Control … Transport Layer Media Gateways API - Application Programming Interface

29. Softswitch Application Server Network Management Server PSTN, GSM, ATM, ... Media Gateway IP network Multiservice Access NGN architecture Services Transport

30. ITU-T NGN architecture (Y.1001) and corresponding protocols IP Network IW Functions PSTN/ISDN • Softswitch includes MGC, SG • Media Gateway is protocol converter • Media Gateway Controller is master • controller of a media gateway • Intelligent Database - Network directory, • Billing, Call records Intelligent Database (ID) . . ID/MGC ID/SG API . . Signaling Gateway (SG) H.323/SIP/SIP-T/ SIGTRAN . CC7/SS7 ISUP SG/MGC MG Controller (MGC) MGC/MGC . . MGC/MG MGCP/Megaco(H.248) . . Media Gateway (MG) RTP Packet Flow (Voice/Data/MM) TDM Flow (Voice)

31. 6.5. Main NGN protocols and building blocks

32. Main control protocols Call Control (Session Control) The ability of a network element to establish new calls. A “call” in the next generation network can be viewed as a session in which the session establishes either a voice conversation or, ultimately, a multimedia (audio plus video) stream. There are two primary call control protocols unique to packet-based networks: H.323 SIP

33. H.323, ITU-T • H.323 - first call control standard for multimedia networks. Was adopted for VoIP by the ITU in 1996 • H.323 is actually a set of recommendations that define how voice, data and video are transmitted over IP-based networks • The H.323 recommendation is made up of multiple call control protocols. The audio streams are transacted using the RTP/RTCP • In general, H.323 was too broad standard without sufficient efficiency. It also does not guarantee business voice quality

34. SIP - Session Initiation Protocol, IETF (Internet Engineering Task Force) • SIP - standard protocol for initiating an interactive user session that involves multimedia elements such as video, voice, chat, gaming, and virtual reality. Protocol claims to deliver faster call-establishment times. • SIP works in the Session layer of IETF/OSI model. SIP can establish multimedia sessions or Internet telephony calls. SIP can also invite participants to unicast or multicast sessions. • SIP supports name mapping and redirection services. It makes it possible for users to initiate and receive communications and services from any location, and for networks to identify the users wherever they are.

35. SIP - Session Initiation Protocol, IETF • SIP – client-server protocol, Rq from clients, Rs from servers. Participants are identified by SIP URLs. Requests can be sent through any transport protocol, such as UDP, or TCP. • SIP defines the end system to be used for the session, the communication media and media parameters, and the called party's desire to participate in the communication. • Once these are assured, SIP establishes call parameters at either end of the communication, and handles call transfer and termination. • The Session Initiation Protocol is specified in IETF Request for Comments (RFC) 2543.

36. IN Control Feature servers provide IN control with legacy central offices and Softswitches. INAP (Intelligent Network Application Part) - a member of the family of SS7 application protocols. Additional IN protocols have also been developed for mobile networks (e.g. GSM-CAMEL).

37. Gateway control The target of the Gateway control - to enable a simple media gateway implementation with intelligence centralized on a media gateway controller (which is also called a call agent or a Softswitch) Two gateway control protocols: Media Gateway Control Protocol (MGCP) as the de facto standard H.248/Megaco as the ITU and IETF approved standard.

38. MGCP/Megaco/H.248 • MGCP - Media Gateway Control Protocol, IETF [Telcordia (formerly Bellcore)/Level 3/Cisco] • MGCP – control protocol that specifically addresses the control of media gateways • Megaco/H.248 (IETF, ITU) - standard that combines elements of the MGCP and the H.323, ITU (H.248) • The main features of Megaco - scaling (H.323) and multimedia conferencing (MGCP)

39. Media Control Media control is a form of device control used for network elements that are specialized for advanced media processing. Media control includes instructions to play and record voice files, collect and generate tones (including DTMF touch-tones), establish N-way conferences, perform fax conversions, generate text-to-speech, and perform speech recognition.

40. Application Program Interface API - routing, billing, call control, and media control on the feature server and application server. The goal of the APIs is to enable: 1. Service logic that is independent of network protocols, network deployment architecture, and reference element architecture to meet the service provider requirement for service ubiquity 2. Services that scale from an entry level integrated solution to a distributed network deployment without modifications, meeting the service provider requirement for low cost infrastructure

41. Main transport protocols Real-Time Transport Protocol (RTP) and Real-Time Control Protocol (RTCP) RTP - for end-to-end network transport of communications services requiring real-time data (i.e., audio and/or video). Real-Time Control Protocol (RTCP) – for data transport monitoring RTP and RTCP are designed to be independent of the underlying network layers (e.g., UDP/IP, MPLS, or ATM). RTP does not address resource reservation nor does it guarantee quality-of-service (QoS). Resource Reservation Setup Protocol (RSVP) Multi-Protocol Label Switching (MPLS) RTP routing over MPLS sessions

42. AAA ID Switch Switch SS7 SS7 PSTN/ISDN PSTN/ISDN Mobile Networks/ IMS H.323/SIP STP STP NGN architecture – possible NGN configuration Network Manager Application Server SNMP RADIUS API (Parlay, LDAP) Softswitch SIP/SIP-T H.323/BICC SG SIGTRAN SG SS7 ISUP SIGTRAN ISUP Softswitch SIP MGC MGCP/Megaco/H.248 Gatekeeper/ Proxy Server Media Gateway Media Gateway CoreIP Network (QoS) Н.323/IP Network

43. B. NGN building blocks • Media Gateway - protocol converter • Media Gateway Controller - master controller of a media gateway • Softswitch = MGC + SG • Signaling Gateway • Application Server – Information Database (ID) - Network directory, Billing, Call records, Authentication, authorization, and accounting (AAA) • Network Manager – Operation, Administration, Management (OAM); provides network elements’ management from a centralized web interface

44. Media Gateway (IETF RFC 3015) Media gateway (MG) – protocol converter between different types of networks (Example – MG between circuit-switched voice network - TDM flows, and the IP network - RTP packet flows.) MG processes incoming calls via requests to the Application Server using HTTP. The media gateway (MG) terminates IP and circuit-switched traffic. MGs relay voice, fax, modem and ISDN data traffic over the IP network using Quality of Service enabled IP technology.

45. Media Gateway (IETF RFC 3015) • All types of traffic (voice, data, video) • Control (from Media Gateway Controller): MGCP, Megaco/H.248 • Interfaces: STM-1to transport network, E1 to PSTN; Eth-Fast/Gb to IP network • Voice Packetization/Compression (Codecs: ITU-T G.711, G.723.1, G.726, G.729A • Echo cancellation: ITU-T G.165, G.168 • QoS via DiffServ and ToS bits marking • Mapping addresses: E.164 IP address

46. Softswitch Signaling Gateway Signaling Gateway (SG) offers a consolidated signaling interface - SS7 signaling point for the NGN platform. Also, SG supports a SIGTRAN interface (IETF SS7 telephony signaling over IP) as well as IP Proxy functions (SIP). Media Gateway Controller • MGC acts as the master controller of a media gateway • Supervises terminals attached to a network • Provides a registration of new terminals • Manages E.164 addresses among terminals

47. Signaling Gateway Function • Several millions BHCA • Several hundreds controlled trunk ports • Control: MGCP, MEGACO, SIP • Signaling: ISUP, H.323, SIP, SIP-T, INAP, SIGTRAN • Mgmt: SNMP IP Signaling SS7 Signaling SIGTRAN ISUP IP Network Signaling Gateway PSTN

48. Application Server Application server – provides the applications (i.e., service logic) for new and innovative services such as unified messaging, conferencing, speech dial tone, and multimedia messaging services. Application servers are typically based on advanced Java tool environments that provide multi-modal integration of voice and data. Application Server generates application documents (VoiceXML pages) in response to requests from the Media Gateway via the internal Ethernet network. The application server leverages a web application infrastructure to interface with data stores (messages stores, user profile databases, content servers) to generate documents (e.g., VoiceXML pages). AS provide interoperability between applications like WAP, HTML, and voice allowing the end user to simultaneously input voice command and receive presentation via WAP or HTML.

49. Appendix A: Parlay Parlay is an evolving set of specifications for industry-standard application programming interfaces (APIs) for managing network "edge" services: • call control • messaging • content-based charging. Parlay specifications are being developed by the Parlay Group, a consortium of member companies that include AT&T, BT, Cisco, IBM, Lucent, Microsoft, Nortel Networks, and others. Use of the Parlay specifications is expected to make it easier to add new cross-platform network applications so that users need not depend solely on the proprietary offerings of carriers. The Parlay Group is not a standards group itself, but sees itself as a facilitator of needed interfaces. Application program interfaces are or will be defined for:

50. Parlay • Authentication • Integrity management • Operations, administration, and maintenance (OA&M) • Discovery (of the closest provider of a service) • Network control • Mobility • Performance management • Audit capabilities • Generic charging and billing • Policy management • Mobile M-commerce/E-commerce • Subscriber data/user profile/virtual home environment (VHE) • The Parlay APIs are said to complement and encourage use of the Advanced Intelligent Network (AIN) protocols.