1. Internet2 spring meeting1 Making the phone not ring Henning Schulzrinne Department of Computer Science Columbia University hgs@cs.columbia.edu Internet2 spring meeting May 3, 2005 (Arlington, VA)

2. Internet2 spring meeting2 Overview Ring-and-hope  presence-mediated communications Uses for presence: Old: “I’m on-line” Location-based services Presence-derived call handling Presence-derived trust Presence and privacy

3. Internet2 spring meeting3 Context-aware communication context = “the interrelated conditions in which something exists or occurs” anything known about the participants in the (potential) communication relationship both at caller and callee timeCPL capabilitiescaller preferences locationlocation-based call routing location events activity/availabilitypresence sensor data (mood, bio)privacy issues similar to location data

4. Internet2 spring meeting4 Evolution of VoIP “amazing – the phone rings” “does it do call transfer?” “how can I make it stop ringing?” 1996-2000 2000-20032004- catching up with the digital PBX long-distance calling, ca. 1930 going beyond the black phone

5. Internet2 spring meeting5 The role of presence Guess-and-ring high probability of failure: “telephone tag” inappropriate time (call during meeting) inappropriate media (audio in public place) current solutions: voice mail  tedious, doesn’t scale, hard to search and catalogue, no indication of when call might be returned automated call back  rarely used, too inflexible  most successful calls are now scheduled by email Presence-based facilitates unscheduled communications provide recipient-specific information only contact in real-time if destination is willing and able appropriately use synchronous vs. asynchronous communication guide media use (text vs. audio) predict availability in the near future (timed presence) Prediction: almost all (professional) communication will be presence-initiated or pre-scheduled

6. Internet2 spring meeting6 Basic presence Role of presence initially: “can I send an instant message and expect a response?” now: “should I use voice or IM? is my call going to interrupt a meeting? is the callee awake?” Yahoo, MSN, Skype presence services: on-line & off-line useful in modem days – but many people are (technically) on-line 24x7 thus, need to provide more context + simple status (“not at my desk”) entered manually  rarely correct does not provide enough context for directing interactive communications

7. Internet2 spring meeting7 Rich presence More information automatically derived from sensors: physical presence, movement electronic activity: calendars Rich information: multiple contacts per presentity device (cell, PDA, phone, …) service (“audio”) activities, current and planned surroundings (noise, privacy, vehicle, …) contact information composing (typing, recording audio/video IM, …)

8. Internet2 spring meeting8 Presence data model “calendar”“cell”“manual” alice@example.com audio, video, text r42@example.com video person (presentity) (views) services devices

9. Internet2 spring meeting9 RPID = rich presence Provide watchers with better information about the what, where, how of presentities facilitate appropriate communications: “wait until end of meeting” “use text messaging instead of phone call” “make quick call before flight takes off” designed to be derivable from calendar information or provided by sensors in the environment allow filtering by “sphere” – the parts of our life don’t show recreation details to colleagues

10. Internet2 spring meeting10 The role of presence for call routing Two modes: watcher uses presence information to select suitable contacts advisory – caller may not adhere to suggestions and still call when you’re in a meeting user call routing policy informed by presence likely less flexible – machine intelligence “if activities indicate meeting, route to tuple indicating assistant” “try most-recently-active contact first” (seq. forking) LESS translate RPID CPL PA PUBLISH NOTIFY INVITE

11. Internet2 spring meeting11 Presence and privacy All presence data, particularly location, is highly sensitive Basic location object (PIDF-LO) describes distribution (binary) retention duration Policy rules for more detailed access control who can subscribe to my presence who can see what when <gml:Point gml:id="point1“ srsName="epsg:4326"> 37:46:30N 122:25:10W no 2003-06-23T04:57:29Z 2003-06-22T20:57:29Z

12. Internet2 spring meeting12 Location-based services Finding services based on location physical services (stores, restaurants, ATMs, …) electronic services (media I/O, printer, display, …) not covered here Using location to improve (network) services communication incoming communications changes based on where I am configuration devices in room adapt to their current users awareness others are (selectively) made aware of my location security proximity grants temporary access to local resources

13. Internet2 spring meeting13 Program location-based services

14. Internet2 spring meeting14 Presence for spam prevention VoIP spam (“spit”) and IM spam (“spim”) likely to be more annoying than email spam Subscription to another person is indication of mutual trust other person allows me to see their status  trusts me Thus, use watcher list (who is watching me) as trust vector

15. Internet2 spring meeting15 Conclusion Media delivery  controlled interaction Binary presence  rich presence Presence as enabler of loosely-coupled advanced services location-based services serve as service script inputs trust indicator for spit/spim prevention

16. Internet2 spring meeting16 Backup slides

17. Internet2 spring meeting17 Presence data architecture raw presence document create view (compose) privacy filtering draft-ietf-simple-presence-data-model composition policy privacy policy presence sources XCAP (not defined yet) depends on watcher select best source resolve contradictions PUBLISH

18. Internet2 spring meeting18 Presence data architecture candidate presence document watcher filter raw presence document post-processing composition (merging) final presence document difference to previous notification SUBSCRIBE NOTIFY remove data not of interest watcher

19. Internet2 spring meeting19 RPID: rich presence