1. Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. SEC: Spontaneous Enterprise Communications Hyong Sop Shim, Chit Chung, Michael Long, Gardner Patton, Siddhartha Dalal April 3, 2001

2. 2 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Outline  Motivation  Functional Requirements  End User Perspective  Design Approach  Architectural Overview  Key SEC Protocols  Implementation  Related Work  Future Work

3. 3 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Motivation  Distributed, team-oriented workplace often requires: –Spontaneous, real-time communications between team/project members –Multiparty communications  “Buddy lists” provide an effective means of spontaneous communications by providing presence and availability information in “real-time”

4. 4 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Functional Requirements  Provide enterprise-wide “buddy lists” –Many are already familiar with the concept of a buddy list and instant messaging  Integrate with enterprise directory  Provide multiple communications media, especially audio and text  Allow spontaneous switching of communication media type  Allow multiple, simultaneous multi-party communications  Enable familiar means of communication, e.g., desktop phones, cell phones, VoIP, and instant messaging  Support mobile users

5. 5 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Presence and Availability List (PAL)  In SEC, when a buddy list item represents a human user: –Presence means “Logged in” or registered with a system –Availability means willingness or capability to communicate  Presence and Availability List (PAL) –Equivalent to “buddy list” –An item on a PAL may be any event source, e.g., buddy, conference, and internet appliances

6. 6 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. End User Perspective: Integration with Corporate Directory “Add to Contact List” “My Contact List” or PAL

7. 7 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. End User Perspective: Spontaneous Conferencing “Add” Contact to Text Conference “Add” Contact or Phone Number to Voice Conference

8. 8 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. End User Perspective: Spontaneous Media Switching “Text” “Talk”

9. 9 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Design Approach  Distinguish communication controller from communication device  Hide device details, e.g., phone numbers and device types  Every call is a conference –Each conference is managed by a “server” or “bridge” –For load balancing, different conferences may be managed by different servers  If possible, delegate audio mixing task to client  Automatic download of PALs upon login or registration

10. 10 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Architectural Overview PAL Manager / Registrar DQ Enterprise Directory DQP PSTN Gateway H.323 RTP SEC Servers SEC ClientsCommunication Devices PAL and Conference ControlCommunication Media Routing SECP HTTP PSTN DQP SIP HTTP RTP SIP HTTP Proxy Comm. Controller MTCUMCU HTTP Proxy PSTN Gateway Proxy User AUser BUser CUser AUser BUser C

11. 11 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. SIP in SEC  SIP used for: –Conference setup and management –Conference membership notification –PAL setup and management –Text message conferencing  Why SIP? –Small number of SIP METHODS –Easy to embed application-specific semantics –Text-based encoding helps testing and debugging process tremendously  SEC server components are not SIP Proxies! –They are SIP endpoints  The current implementation does not make use of SIP REFER for conference management

12. 12 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Conference Setup Comm. Controller MTCU/ MCU User A’s SEC Client PAL Manager User B’s SEC Client INVITE To: SEC From: USER_A CREATE CONF_X 200 Okay CREATE CONF_X 100 Trying To: SEC From: USER_A 302 Temporarily Moved To: SEC From: USER_A Contact: CONF_X ACK To: SEC From: USER_A CREATE CONF_X 200 Okay CREATE CONF_X

13. 13 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Caller Joins Conference Comm. Controller MTCU/ MCU User A’s SEC Client PAL Manager User B’s SEC Client INVITE CONF_X To: CONF_X From: USER_A “SD” JOIN CONF _X USER_A “SD” 200 Okay JOIN CONF_X USER_A CONF_X_SD 180 Trying 200 Okay “CONF_X_SD” ACK To: CONF_X From: USER_A SUBSCRIBE To: CONF_X From: USER_A 200 Okay “CONF_X_PA” JOIN CONF_X USER _A 200 Okay JOIN CONF_X USER_A

14. 14 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Caller Invites Callee to Conference Comm. Controller MTCU/ MCU User A’s SEC Client PAL Manager User B’s SEC Client INVITE CONF_X To: USER_B From: USER_A JOIN CONF_X USER_B “SD” 200 Okay JOIN CONF_X USER_B CONF_X_SD 180 Ringing 200 Okay INVITE To: USER_B From: CONF_X Contact: CONF_X “Participant: USER_A” 200 Okay “SD” 180 Ringing ACK CONF_X To: User_B From: USER_A JOIN CONF_X USER_B 200 Okay JOIN CONF_X USER_B

15. 15 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Caller Invites Callee to Conference (cont.) Comm. Controller MTCU/ MCU User A’s SEC Client PAL Manager User B’s SEC Client NOTIFY To: USER_A From: CONF_X “CONF_X_PAL” 200 Okay ACK From: CONF_X To: USER_B “CONF_X_SD” SUBSCRIBE To: CONF_X From: USER_B 200 Okay “CONF_X_PA”

16. 16 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Implementation  SIP stack developed in-house and in Java (an earlier version tested at a SIP Bakeoff)  PSTN Gateway Proxy developed in-house on a commercial H.323 stack  Cisco AS5300 used to interface with PSTN  Client audio module uses Microsoft DirectSound  G.711

17. 17 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Related Work  Commercial Instant Messaging Systems  Commercial IP or PSTN Conference Bridges  Academic and lab systems

18. 18 Copyright © 2001 Telcordia Technologies, Inc. All rights reserved. Future Work  Security  Performance –Scalability w.r.t. server components –Scalability w.r.t. voice codec  New services –e.g. video –e.g. collaboration –e.g, automatic PA management