International SIP 2008

1. Interworking between P2PSIP Overlays and IMS Networks: Why? How? Enrico Marocco and Gianni Canal Telecom Italia Lab {enrico.marocco, gianni.canal}@telecomitalia.it International SIP 2008

2. Outline • Real-time communications are changing • Services vs. applications • What has been done so far? • What else can be done? • Peer-to-peer SIP • Why is it better than other technologies? • P2PSIP/IMS interworking scenarios • What is missing? • Conclusions

3. Internet Companies Enrich the web experience with new and low-cost real-time communications applications e.g. GTalk, Yahoo! Big success factor: cheap calls towards regular phones e.g. Skype, SIPphone, Jajah What's happening to real-time communications? Telephony Service Providers • Exploit IP to build one access-agnostic service architecture • Legacy requirements • Easy deployment of new services • Enter the new (Internet) world • e.g IM, Chat, Second Life

4. What can we do? • Ignore • We cannot compete in the “Internet” world • All in all, they push more bits in our pipes and pay us for call termination • Impede • Technically feasible • Saved earnings exceed loss due to unsatisfied subscribers • Leverage • Let our subscribers call their “net buddies” • Let third party applications access our telecom capabilities • e.g. identity, voice-mail, payments, storage • Take care of the “interconnection” part • Provision of PSTN/PLMN interconnection requires big investments

5. What have we done so far? • Branded VoIP+IM+telephone applications • Better than the originals • Connect with GTalk, Yahoo!, MSN [...] for free • Let make calls just as regular phones! • But users do not like them (YMMV)

6. The “Wengo” lesson • One of the few Skype competitors • Open source application bound to Wengo SIP service • Free VoIP/IM, cheap calls/SMS • Worldwide community • Service ecosystem • Wengo is NEUF Telecom... • Direct connection with paying users • vs. skypeout earnings, split between Skype and local operators • ... but users do not feel it • The operator can work as a back-end for communities • Contribute resources and sell services • Let the control to people

7. Dealing with people over the Internet • Approach established communities • Different technologies • Need agreements • Establish new communities • Significant investment • Extreme competition

8. REGISTER REGISTER INVITE INVITE INVITE INVITE INVITE Peer-to-peer SIP Hardware Bandwidth Fault Tolerance Configuration Management

9. P2PSIP: SIP for everyone • Good for Internet companies/communities • Build cheap solutions • Public service providers • Ad-hoc networks • Small scale IP-PBX • Connect with other networks • Good for Telecoms • Provide traditional services in other market segments • Calls between phones and web applications • Subscribers easily access their home network profiles • Free competition for service provision • e.g. interconnections, conferences, payments...  peer-to-peer  SIP  SIP  peer-to-peer

10. Calls between heterogeneous clients sip:alice@p2psip.org telecomitalia.it tel:+39-335-55-66-777 sip:bob@telecomitalia.it p2psip.org

11. Providing services to peer-to-peer clients sip:alice@telecomitalia.it sip:alice@p2psip.org REGISTER sip:p2psip.org SIP/2.0 To: sip:alice@p2psip.org From: sip:alice@p2psip.org Contact: sip:alice@172.16.0.123 telecomitalia.it REGISTER sip:telecomitalia.it SIP/2.0 To: sip:alice@telecomitalia.it From: sip:alice@telecomitalia.it Contact: sip:alice@p2psip.org p2psip.org

12. IMS IPv4/IPv6 gateways NAT traversal enabled on clients SIM-less authentication Peering policies Gaps P2PSIP • Traffic relay in limited connectivity environments • Global reachability (DNS) • Service discovery

13. Conclusions • Differentiation in real-time communications • “Services and applications” better than “services vs. applications” • “Offer” rather than “control” to succeed on the Internet • P2PSIP can enable IMS-friendly cheap communication services • P2PSIP overlays can be a marketplace for telecom operators • Topical issues to be addressed in IETF and 3GPP