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This talk explores the value and potential improvements in voice communications through the use of VoIP (Voice over IP) technology. It covers topics such as cost savings, replacing traditional telephone services, improving fidelity and privacy, addressing, mobility, media translation, survivability, integration with other applications, and presence. The talk also discusses the importance of connectivity and the role of middleware in enabling communication between applications. Lastly, it highlights the use of SIP (Session Initiation Protocol) in creating, modifying, and terminating real-time internet media sessions.
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National Internet2 DayMarch 18th, 2004 Ben Teitelbaum, Internet2<ben@internet2.edu> For this and other talks... http://www.internet2.edu/~ben/talks.html Connectivity for Advanced VoIP and Integrated Communications
Personal Communications Highest value applications are generic Email, telephone, postal mail Throughout the history of communications, generic person-to-person communications have dominated content distribution and domain-specific apps Voice The dominant real-time communications medium A "killer" network application for >100 years VoIP opens doors to make voice communications even more valuable
Long promised, but still inevitable Has happened in the core Happening now for residential / enterprise Drivers Cost, cost, cost, cost, cost Why have a giant switch, two networks, two staffs, etc.? Voice is just another network application Dampers QoS, 911, CALEA, USF, FUD Little user "pull" Voice / Data Convergence
Replace or Displace? If voice is so important, why be satisfied with replacing plain-old telephone service (POTS)?! Users are already defecting to cellular, SMS, AIM, MSN Messenger, Yahoo!, etc. VoIP can be much better than POTS Potential dimensions of improvement Fidelity Privacy Addressing Mobility Media translation Advanced Voice • Survivability • Integration with IM, video, etc. • Presence • "911++"
Replace or Displace? If voice is so important, why be satisfied with replacing plain-old telephone service (POTS)? Users are already defecting to cellular, SMS, AIM, MSN Messenger, Yahoo!, etc. VoIP can be much better than POTS Potential dimensions of improvement Fidelity Privacy Addressing Mobility` Media translation Advanced Voice • Survivability • Integration with IM, video, etc. • Presence • "911++" Not covered here, but Internet2 projects in these areas exist Covered in this talk
Connectivity "Paths in the snow" Don't predict how users will want to communicate Users are highly-motivated to communicate with each other and to innovate Connect them and watch what happens Witness: P2P file-sharing Network connectivity + middleware = P2P FS Similar potential for real-time apps We should get ahead of the curve this time and provide the enabling middleware ourselves
Connective Middleware Application connectivity: Are there protocols and call routing infrastructure to establish connections between communicating applications? Application Connectivity Addressing Addressing (SIP/SIMPLE call and presence routing) RichPresenceServices RichPresenceServices Network Connectivity (high-performance, end-to-end IP transit) Network connectivity: Can connections be established between communicating IP addresses with high-performance and high-availability? User connectivity: Can I reach you? User User
Demographics ~3.8 million students (tech-savvy, talk a lot, adapt easily) And, by the way, they graduate (tech-transfer à la email) Institutional Commitments Internet2 members have committed to advance IP communications and promote collaborative apps Many are looking for ways to reverse eroding voice revenues Connectivity Great networking connectivity High-bandwidth, low-loss, low-jitter End-to-end transparency (few NATs) IPv6 and multicast too! Emerging middleware infrastructure for AuthN/Z Need to build on this to connect users with each other! Internet2's Secret Sauce
SIP.edu What’s “SIP”?
SIP Signalling protocol for creating, modifying, and terminating real-time internet media sessions SIP (and its extensions) support traditional telephony features as well as instant messaging and presence Attributes Provides: user registration, call routing, setup, tear down, and redirection Makes heavy use of existing standards Easy and familiar feel (email-style headers, HTTP-style error codes, URL addresses) Signaling and media paths separate SIP: Session Initiation Protocol (RFC 3261)
SIP Trapezoid INVITE sip:bob@b.edu Proxy Proxy Registrar Registrar Alice's hardphone Bob's softphone Media (and subsequent signaling)
Vigorous standards activity SIP (core protocol and extensions) • SIPPING (applications) • SIMPLE (instant messaging and presence) • not just IETF, 3GPP too! Enthusiastic industry adoption Phones (Microsoft, Cisco, Pingtel, Snom, ...) Servers (Cisco, Microsoft, Broadsoft, ...) Conferencing (eDial, RADVision, ...) Services (Level3, WorldCom, Vonage, ...) Open source software Servers: SER (iptel.org) • VOCAL (vovida.org) Soft Phones: Linphone • KPhone SIP Happens
Fearless Leader Dennis Baron <dbaron@mit.edu> Goals Grow number of SIP connected users Increase value proposition for end-user SIP adoption Promote convergence of voice and email identity Low entry-cost means for campuses to... Provide a useful service Start getting their feet wet with SIP Means “SIP.edu cookbook” available on web site Partnering with vendors (Cisco working with 6 schools) SIP.edu
Addressing Users should not be burdened with device addresses, when it’s people they really care about Addresses should be mnemonic and empower enterprises to manage the identities of their users sip:ben@internet2.edu It’s time to put E.164 phonenumbers behind us! A.G. Bell did not say... Remember: It's People We Are Connecting “+1-617-637-8562, come here. I need you!”
SIP.edu Architecture (today) SIPProxy SIP-PBXGateway PBX DNS CampusDirectory SIP User Agent INVITE(sip:bob@bigu.edu) DNS SRV query sip.udp.bigu.edu bigu.edu PRI / CAS INVITE(sip:12345@gw.bigu.edu) sip. udp.bigu.edu IN SRV ... telephoneNumberwhere mail=”bob” Bob's Phone
SIP.edu Architecture (real soon) If Bob has registered, ring his SIP UAs; Else, call his extension through the PBX. SIPProxy DNS SIPRegistrar locationDB SIP User Agent INVITE (sip:bob@bigu.edu) DNS SRV query sip.udp.bigu.edu bigu.edu INVITE (sip:bob@207.75.164.131) REGISTER(Contact: 207.75.164.131) Bob's SIP Phones
SIP.edu Growth >8 other schools working on it
Presence and Integrated Communications Presence “Notification of events that facilitate communication” (Henning Schulzrinne) “On-line”, “Away”, “Idle”, “On phone”, “Out to lunch”, ... Back to the future? Remember: finger, write, who? Presence restores the sense of community that existed on timesharing systems Forward to the future! New standards for interoperability and scalability User-centric control of presence publication Richer state semantics and automatic triggers
Rich Presence Trials Indianapolis October, 2003 Honolulu January, 2004 Arlington April, 2004
Client Mockup WaveThree Software and Columbia U. have provided clients (Session, SIPC) Others welcome! (client requirements doc on web)
Chairs Walt Magnussen <wmagnussen@ppfs4.tamu.edu> Mike Enyeart <enyeart@indiana.edu> Web site http://voip.internet2.edu/ Projects SIP.edu Voice Disaster Recovery H.323 VoIP Testbed VoIP Working Group
Chair Jermey George <jeremy.george@yale.edu> Web site http://pic.internet2.edu/ Projects Rich Presence Trials Social Context Study Group Presence and Integrated Communications Working Group