1. March 10, 2008SIPPING WG IETF-711 Secure Media Recording and Transcoding with the Session Initiation Protocol draft-wing-sipping-srtp-key-03 Dan Wing Francois Audet Steffen Fries Hannes Tschofenig Alan Johnston Note: IPR disclosure by Avaya

2. March 10, 2008SIPPING WG IETF-712 New Sections on Use Cases Recording Modes –Always On Recording –Recording On Demand –Required Recording –Pause and Resume Recording Recording Call Flows –Always On Recording –Recording On Demand –Required Recording –Pause and Resume Recording Call Flow –Conference Recording

3. March 10, 2008SIPPING WG IETF-713 Changes Recorder as a SIP UA instead of an invisible packet sniffing device A Controller as a B2BUA in the middle –Similar to a Focus B2BUA which has been standardized by the IETF –Only Role is to INVITE Recorder and copy media stream to recorder No mixing –Avoids Having only special UAs in recording scenarios Double bandwidth problems at endpoint Doing recording in endpoint UA still OK, it just does not require as much standardization

4. March 10, 2008SIPPING WG IETF-714 Alice Controller Bob Recorder | | | | | INVITE F1 | | | |--------------->| | | |(100 Trying) F2 | | | |<---------------| INVITE F3 | | | |--------------------------------->| | | | 200 OK F4 | | |<---------------------------------| | | | ACK F5 | | |--------------------------------->| | | INVITE F6 | | | |------------->| | | |180 Ringing F7| | | |<-------------| | | 180 Ringing F5 | | | |<---------------| 200 OK F6 | | | |<-------------| | | 200 OK F7 | | | |<---------------| | | | ACK F8 | | | |--------------->| ACK F9 | | | |------------->| | | | INVITE F10 | | | |--------------------------------->| | | | 200 OK F11 | | |<---------------------------------| | | | ACK F12 | | |--------------------------------->| | Both way SRTP Established | | | | | | | | SRTP From Alice | | |=================================>| | | SRTP From Bob | | |=================================>| Figure 1: Controller Proxy or B2BUA

5. March 10, 2008SIPPING WG IETF-715 Alice Focus/Mixer Bob Recorder | | | | | | SUBSCRIBE F1 | | |<---------------------------------| | | | 200 OK F2 | | |--------------------------------->| | | NOTIFY F3 | | | |--------------------------------->| | | | 200 OK F4 | | |<---------------------------------| | INVITE F5 | | | |--------------->| | | | 200 OK F6 | | | |<---------------| | | | ACK F7 | | | |--------------->| | | | SRTP | NOTIFY F8 | | | |--------------------------------->| | | | 200 OK F9 | | |<---------------------------------| | | INVITE F10 | | | |<-------------| | | |180 Ringing F11 | | |------------->| | | | 200 OK F12 | | | |------------->| | | | SRTP | | | | | | | | NOTIFY F13 | | | |--------------------------------->| | | | 200 OK F14 | | |<---------------------------------| | | INVITE Join: A-B F15 | | |<---------------------------------| | | | 200 OK F16 | | |--------------------------------->| | | | ACK F17 | | |<---------------------------------| | | Mixed SRTP from Alice and Bob | | |=================================>| Figure 4: Conference Recording Call Flow

6. March 10, 2008SIPPING WG IETF-716 No Changes To Key disclosure mechanism –UA must cooperate and publish the key to the recorder –Some sort of disclosure like ZRTP Event package –Still needs work

7. March 10, 2008SIPPING WG IETF-717 Conclusion Is the working group interested in working on –SIP call recording call flows? –Requirements? –Mechanisms?