1. APIs for Next-Generation Service Creation Jonathan Rosenberg Chief Scientist

2. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Voice Over IP Today Toll-bypass has Been the Primary Motivation Cheap long distance Service transparency Cost Differentials are Rapidly Disappearing Retail long distance is now at 4 cents a minute Carriers are exploring flat rate plans Service Transparency is Far Away QoS issues 911, 1000 features in the 5ESS Huge existing penetration of the phone in the US and worldwide

3. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation The Question of Customer Value If IP Telephony Service is Not Cheaper, Better or Different, Why Purchase It?

4. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation The Answer IP Telephony Enables Innovative New Services Created by Combining Applications Web Email Chat Presence The Killer App for VoIP Lives Within These Combined Services

5. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Combined Services Enable Service Provider Differentiation Integrating Applications Yields Exponential Services Growth Service Provider Differentiation Flows Naturally from this Applications Diversity Combined Services Voice Voice + Web Voice + Web + Email Voice + Web + Email + Presence

6. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Web Interactive Voice Response (Web IVR) IVR Woes Difficult to navigate Inconsistent menu operations Slow to use Big Idea Web a natural medium! How Does It Work If a call to some number is from a PC, after hours, the user is returned a web page If the call is from a phone connected to a gateway, they are connected to a normal voice system INVITE HTTP Web Content Web IVR Service INVITE VoiceXML Gateway PSTN Phone PCWeb Server 200 OK 300 Go Web

7. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation How to Build These Services? Need APIs That Provide Access to SIP Specific Constructs Many combined services rely on SIP support for MIME, URLs, etc. Web IVR requires setting of the Contact header to an HTTP URL Auto Conference requires SIP IMs to contain HTTP URLs Signaling protocol independent APIs wont work Parlay JTAPI The call is not the central feature of the application any longer State machine exists at a higher level Call machine not important

8. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation How to Build These Services? Leverage the Vast Web Developer Community Web developers to telecom developers is 100:1 Every graduate CS student has done some web programming, almost none do telecom programming Innovation will come from two guys in a garage How to Leverage Them? Provide APIs similar to ones they already know Servlets, JSP, CGI, XML APIs shouldnt require telecom training or background Open, widely available Free servers for trial Books, magazines, developer communities Business Models Have an Implication Too!

9. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Changes In Web Business Models Best-in-class companies have emerged at every layer of the business model Applications Transport AOL CompuServe Prodigy ASPs Applications & Hosting Backbone ISP Yahoo UUNET Hosting Companies ASPs Application Developers Application Platforms BEA WebLogic IBM WebSphere Ecommerce.com Accenture Exodus Backbone ISP UUNET ASPs Amazon.com Exodus Hosting Companies Backbone ISP UUNET Vertical Monolith Relentless Specialization

10. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Changes In Telco Business Models Applications Transport AT&T Communications ASPs Applications & Hosting Converged Carriers Dialpad Webley Level (3) Genuity Vertical Monolith Relentless Specialization Communications ASPs Hosting Companies Converged Carriers Level (3) Genuity Hosting Companies Communications ASPs Application Developers Application Platforms Converged Carriers Level (3) Genuity What were once Voice Services are now split between converged applications and converged networks

11. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation How to Build These Services? Follow the business models as well! Relentless specialization Benefits Rapid time-to-market Reduced costs Focus, focus, focus API Implications APIs must support separation of developer and hoster Servlets!

12. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation HTTP Servlets HTTP Java Servlets Widely Used in Web Application Development Applications Consist of Sets of HTTP Servlets, Each of Which Processes a Single Web Request in the Application HTTP Servlets Return Web Pages to Display HTTP Servlets Can Create Session Data e.g., shopping cart, that spans multiple requests Container Manages HTTP Servlet Lifecycles, Fault Tolerance, Session State HTTP Servlets Collected into a War File – Web Archive HTTP Servlets Web Server Developer Deployer War File

13. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation SIP Servlets Direct Application of HTTP Servlet Model to SIP Java-based API Telecommunications application is a set of SIP (and HTTP!) servlets SIP servlets process a particular SIP request or response SIP servlets can create and access session data, call data, transaction data SIP servlet container provides same functions as http container CAR file equivalent of WAR file SIP Servlets Car File SIP Server Developer

14. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation SIP Servlet Benefits Exposes key SIP headers, but handles most of the SIP details for you Supports Sending responses Proxying requests Initiating requests Allows proxy, B2BUA applications Calls, legs, transactions are modeled – similar in concept to HTTP Sessions Inherits all scale and fault tolerance benefits of HTTP Servlets public class MyServlet extends SipServlet { public void doInvite(SipServletRequest req, SipServletResponse res) { req.getProxy(true).proxy(sip:user@host) ; }

15. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Call Processing Language (CPL) Output of IETF IPTEL Group, Under IESG Review Now A Scripting Language to Describe Call Services Language Properties Guarantee Safety Based on XML Hand or Tool Authoring Example: Call Forward on Busy/No-answer Can Be Dynamically Uploaded and Instantiated by Third-parties

16. www.dynamicsoft.com SIP 2001 2.23.01 APIs for Next-Generation Service Creation Common Gateway Interface (CGI) HTTP CGI Widely Used in Web Servers Predates Servlets Similar Model to Servlets Primary Differences Web server spawns a separate process to handle request Request data passed through environment variables Web page returned by script by writing to standard out (stdout) – i.e., printf Script can be written in any language Big process overhead SIP CGI is Direct Equivalent to HTTP CGI, Just as SIP Servlets are Direct Equivalent to HTTP Servlets SIP CGI Properties Scripts invoked on requests and responses Scripts can output response to send and also cause requests to be proxied Same flexibility/overhead as HTTP CGI Approved as Informational RFC 3050 by IETF

17. Information Resource Jonathan Rosenberg Chief Scientist +1 973.952.5000 jdrosen@dynamicsoft.com