SIP: Bridging the Chasm Between Legacy and Next-Generation Networks

1. SIP: Bridging the Chasm Between Legacy and Next-Generation Networks Peter KuciakUbiquity Softwarepeterk@ubiquity.net Internet TelephonyMiami, Feb 5-7th, 2003

2. About Ubiquity • Ubiquity Software is a telecommunication software development company • We offer a platform that greatly simplifies the creation process for telecom application developers • Deploy an architecture that separates applications from network resources • Define and deliver applications that are truly business-oriented • Private global company, 100 people, well funded • Products deployed and in trials in over 20 carriers worldwide

3. This Presentation • What you will see • Evolution discussion of the old and the new network models • Approach of bridging them to create the best of both worlds • Many examples of applications and services that bridge legacy and NGN networks thus creating exciting services • What you will NOT see • Tutorial on SIP or SS7 or any other protocol • Ramblings about specific technical details • Self promotion

4. Market comparison – SS7 & VoP • SS7 • In 2000 almost $10 billion shipped • Down from over $12 billion in 1998 • Voice over Packet • In 2000 under $1 billion shipped • Predicting $1.6 billion by 2005 • SS7 still very much dominant – with growth especially in Asia + Latin America • Wireless not based on VoP – 3G promises all IP • NGN needs bridges to legacy world – can not ignore and assume green field scenario

5. Architectual Evolution Parallel Development Next-Gen Network Next-Gen Services Existing Network Next-Gen Services Service Evolution ? Next-Gen Network Existing Services Existing Network Existing Services Network Evolution ?

6. Why the Evolution to IP? • Why would one want to consider IP ? • Offload traffic to IP = save money • New services in SS7 (caller ID, wireless roaming, SMS) = incredible growth. Over 360 billion SMS messages in 2002 !!! And SMS is only breaking into North America. • Tunnel SS7 over IP = save money • SP leasing SS7 circuits can pay up to $10/mile on international coverage. Jumping to IP virtually eliminates this cost + SP’s save money on STP ports!!!. • Introduce new services = make money • SP creates a new converged service and offers it to customers. MMS, Click-to-dial, Dial-a-taxi, SMS for parking all generate new revenue from users.

7. Distributed Services Model service service service switch switch switch switch switch switch Before SIP … • Service creation closely tied with capability of the “switch” • Switch specific syntax & environment • Creating new services a “challenge” ITU • Vertically Integrated • Central Control • Switching UNI NNI NNI UNI Source: Henry Sinnreich, WorldCom

8. Distributed Services Model Router Router Router Router Router • Open environment • End-to-end service creation • Standards based components SIP and friends… IETF Elected Server Server • Distributed Control • Simple Architecture • Routing Source: Henry Sinnreich, WorldCom

9. Why SIP ? • The IP model is a technological, economic and cultural phenomenon • Born of the Internet - the IP world has thrown its weight behind it • IETF • 3GPP • Promise of much-needed value for tired voice services • Converged services at last!

10. SIP session layer Application Charging Person Mobility Terminal Mobility THE ISV COMMUNITY Session Mobility Instant Messaging Application Layer Presence Always-On Session Layer Session Charging Transport Layer Switching & Routing User-Friendly Addressing Personalization

11. Important Trends … • Web model has taught us that services can be created at the edge • Encourages rapid introduction and global availability of new applications • Offers immediate, global availability • The Applications Server and Web Services markets are exploding • Huge ISV community is developing on J2EE and .NET • Telecom services should follow the same models • The PSTN, mobile networks and Web seem destined to meet • Converged applications will offer compelling benefits • But many protocols must now learn to live in harmony • Standardization by consensus encourages rapid adoption of new technologies • W3C & IETF vs ITU • Session Initiation Protocol is gaining momentum • Powerful protocol is accepted in the industry

12. User-centric not device-centric

13. But there are still issues … • Single protocol “panaceas” have not delivered • New technology cannot be deployed without business case justification • Monolithic solutions have led to vendor lock-in for application development • Today’s open development environments are typically data-centric • Service providers are struggling to accelerate the introduction of real applications to boost profitability and increase ARPU

14. Value of Services … $19 ARPU Total = $61 per subscriber from about $20! Infotainment $7 Intranet Extranet $2 Internet access $8 Multi Media Messaging $4 Location $1 Rich voice $20 Basic voice Source: UMTS Forum

15. SIP and Friends (IP Gang) • PINT • PSTN/Internet Interworking Service - extensions to SIP and SDP for IP Access to Telephone Call Services (RFC2848) • SPIRITS • Service in the PSTN/IN Requesting InTernet Service (RFC3298) • SIGTRAN • SIGnaling TRANsport - transport of packet-based PSTN signaling over IP networks (RFC2719) • MEGACO • Protocol used between elements of a physically decomposed multimedia gateway (RFC3015) • ENUM • Use of the Domain Name System (DNS) for storage of E.164 numbers (RFC2916) • WTA • WAP Telephony Applications • TRIP • Protocol used for routing telephone calls inside an IP network and for locating gateways • SIP-TSI • LOOK AT SIPCENTRE DEFINITIONS !!!

16. SIP Service Capabilities • Services oriented around the customer not around a device • Inherent capabilities: • Multimedia sessions (not just voice!) • Instant Messaging • Presence (status of users and events) • 3PCC • Easily programmable • Integrates with web applications

17. Where should services reside? Point of Interconnect? IP Network? PSTN?

18. Hybrid world – just telephony! Softphone IP Phone SS7 Softswitch IP (SIP/H323) PSTN Analogue Phone Gateway

19. IP network architecture DHCP User Profile Database DNS Server IP SIP Phone Firewall Firewall SIP Phone SS7 Softswitch IP SIP -Enabled Router PSTN Analogue Phone Analogue Phone Gateway SIP Server IP SIP Soft User Agent (H.323)

20. Hybrid world apps and media? IP SIP Server SIP Soft User Agent Service Creation Environment User Profile Database Application Services Broker IN Service Creation Environment Link at what level? Link for what reason? SS7 SIP Phone Softswitch SIP -Enabled Router PSTN Analogue Phone Analogue Phone Gateway

21. Service creation and delivery • A myriad of possibilities: CPL, JAIN, “open” APIs, SOAP, CGI, Servlets • Challenges: • Cross platform implementation of APIs • How “open” is open – just another way to say proprietary? • Where is the service code – integrated , distributed? • What classes of users exist for Service Creation? • Administrators, Subscribers, operators … • How is the service actually “created”? • GUI, Proprietary all-in-one, Legacy Integration?

22. Programming SIP • Service provider revenues will come from intelligently tying together a number of different features to create targeted, differentiated services • A multiplicity of possibilities • SIP is the thread that ties together voice, web, email, video, text • SIP is a textual language based on the request-response paradigm • Its similarity to HTTP will make it a familiar language for web programmers • Utilise the body of web programmers out there • The call is not the central feature of the application any longer • There are a number of different APIs with differing characteristics

23. Call Processing Language (CPL) <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE cpl SYSTEM "cpl.dtd"> <cpl> <location url="sip:jones@pc.ex.com"> <proxy timeout="8s"> <busy> <location url="sip:jones@vmail.ex.com”> <proxy /> </location> </busy> <noanswer> <location url="sip:jones@vmail.ex.com”> <proxy /> </noanswer> </proxy> </location> </cpl> • End-user service creation – An XML-based scripting language for describing call services • Primitives for making decisions and taking actions based on call properties (e.g. caller, time) • CPL can be uploaded to the network, then instantly verified and instantiated • Limited scope means server’s security won’t get compromised • Portability allows users to move CPL scripts across servers • Scripts may be manually written, generated using GUI tools, 3rd parties….

24. SIP CGI • The Common Gateway Interface (CGI) has served as a popular means of programming web services • CGI scripts have been the initial mechanism to make websites interact with databases and other applications • Like HTTP CGI, a SIP CGI script resides in the server and passes message parameters through environment variables to a separate process. The process sends instructions back to the server through its standard output file descriptor. SIP CGI is almost identical to HTTP CGI and is particularly suitable for services that contain substantial web components • A CGI script can be written in Perl, Tcl, C, C++ or Java making it accessible to a large community of developers • Unlike Web-CGI, SIP-CGI supports proxying and processes responses as well

25. Servlets … • An HTTP servlet is a Java application that runs in a Web server or application server and provides server-side processing, typically to access a database or perform e-commerce processing • It is a Java-based replacement for CGI scripts, Active Server Pages (ASPs) and proprietary plug-ins written in C and C++ • Similar to the CGI concept but, instead of using a separate process, messages are passed to a class that runs within a JVM (Java Virtual Machine) inside the server

26. … Servlets cont’d • SIP Servlets are very similar to HTTP Servlets; they simply enhance the interface to support SIP functions • Servlets are portable between servers and operating systems • Compromise between security and power: still a powerful generic language but security provided by Java “sand-box” • A well-defined API is needed. As APIs are not IETF’s business this work moved to JAIN • http://java.sun.com/products/jain/index.html

27. JAIN • JAIN (organised by Sun in 1998) is being specified as a community extension to the Java platform • It provides a new level of abstraction and associated Java interfaces for service creation across PSTN, packet and wireless networks • Objective is to create an open value chain • Service portability • Network convergence • Secure network access (JAIN Parlay) JAIN Application Layer (Call Model) Service Layer (SIP) (IN/AN) JAIN Protocol Layer (Packet Based) (Wireline) Network Layer

28. Parlay • Parlay is complementary with the JAIN umbrella activities • The target market for these APIs are carriers and independent software vendors • Initial efforts focused on call control, messaging and security • The Parlay API passes on IN functionality to third parties while hiding the complexity of the underlying signalling • Java provides an ideal mechanism to make Parlay services available • Parlay can expand the reach of the JAIN community by providing security elements

29. Service capabilities • Location-based services • Presence triggered services • Enhanced web services • Profile-based services • Entertainment • Information Services • Financial Services • Conferencing

30. Defining The Role Of An Applications Server GOAL: To harness the extensive experience, knowledge and energy of the Web Development Community to enable Carrier customers to bring new, compelling communication applications to market quickly & cheaply • The communications Applications Server must directly address the needs and requirements of the target trusted ISV community • The development platform must be standards-based and provide abstracted connectivity to a multitude of commonly used network resources, signaling systems and information systems • hiding the complexities of direct interaction with discrete network resources and signaling mechanisms • The solution must provide mediated user-level service interaction, not simply device-level interaction (as with existing Web Apps Servers) • And should provide common, re-useable, interfaces to those networks resources along with managing the interaction between distinct resources • Applications Server must allow deployment of developed applications and services in a Carrier environment with expected Carrier grade parameters.

31. Example: Stock notification service Subscribe to movements of stock NOTIFY USCL $21.85 Stockbroker SUBSCRIBE • Stock reaches threshold • Notification sent to UA • Click-to-dial stockbroker

32. Example: Utilising Web Services Translation Server SMS Gateway Bonjour, tout le monde! Hello, everybody! Application Server SIP Network PSTN • Send an instant message • Forward message to a translation server e.g. Altavista’s Babelfish • Translated message returned and forwarded to an SMS gateway • Message delivered to mobile phone! • All existing web services with SOAP interfaces! • Take it one step further and generate voice file and play to the user instead of sending text

33. Example: User Mobility / Call Centre Contact List SIP:pkuciak@ubiquity.net TelUrl:5691 192.198.40.2 ring TelUrl:5691 ring 192.198.40.2 SIP: pkuciak@ ubiquity.net ring Location Server REGISTERED USER SIP: pkuciak@ubiquity.net CONTACT: TelUrl:5691 Phone SIP:pkuciak@ubiquity.net REGISTERED USER SIP: pkuciak@ubiquity.net CONTACT: 192.198.40.2 Media Gateway Desktop UA REGISTERED USER SIP: pkuciak@ubiquity.net CONTACT: SIP:pkuciak@ubiquity.net SIP:pkuciak@ubiquity.net SIP enabled Mobile Device

34. Example: User profiling SEND TO VM REGISTER Unknown caller CALL OK CALL OK REGISTER Boss Voicemail Server PROFILE IP Network (fixed/mobile) Wife jim@home.net jim@work.net • Services Associated With a User Not a Device • User may have Multiple Associations • Presence Management for Single ‘Number’ Reachability • Selective Call Forwarding Based on Profile • E.g. Unknown Caller Transferred to Voicemail

35. Example: Enhanced Presence Friends budy list Fred…. Busy Bert……. Free (Fix) Harry……. Free (Mob) Romeo…… Free (PC) Notify Notify Notify Notify TIME 6pm – 11pm SUBSCRIBE EVENT: After 6pm Presence Friends List Send Text Message = mobile Voice Message = phone Mail = PC Presence Server SUBSCRIBE EVENT: After 6pm Presence Friends List Bert Romeo SUBSCRIBE EVENT: After 6pm Presence Friends List SUBSCRIBE EVENT: After 6pm Presence Friends List Harry Fred

36. Conclusions • Open, distributed architectures foster innovation • Architectures that bridge legacy and NGN will allow for greatest range of convergent apps • Abstracted services layer opens up network to third party developers • Subscribers are not restricted to services offered by their operators • Convergence of business models in an Internet-style value chain