DATA CHANNEL FOR CLUE CHRISTER HOLMBERG CLUE VIRUTAL INTERIM MEETING 27th January 2014

DESIRED OUTCOME Decide whether we will use the data channel mechanism defined in RTCWEB for CLUE Decide how/what/where to document the data channel usage for CLUE

OUT OF SCOPE Impact on CLUE session when data channel is removed (with or without explicit signalling) – Yes, we DO need to specify that also – later. Usage of draft-ejzak-dispatch-webrtc-data- channel-sdpneg-00 – Does NOT affect the content in this presentation We first need to agree on the basics Not an alternative, but an extension, to the rtcweb data channel – Provides data channel usage information in SDP

PROTOCOL STACK

RTCWEB DATA CHANNEL BIDIRECTIONAL RTCWEB DATA CHANNEL UNIDIRECTIONAL SCTP STREAM #1 UNIDIRECTIONAL SCTP STREAM #2

RTCWEB INTEROPERABILITY

RTCWED DATA CHANNEL PROTOCOL: DATA_CHANNEL_OPEN | Msg Type | Ch Type | Priority | | Reliability Parameter | | Label Length | Protocol Length | | | | Label | | | | | | Protocol | | |

DATA_CHANNEL_OPEN: CLUE USAGE Header FieldCLUE Usage Value Message Type0x03 (Not CLUE specific) Channel TypeDATA_CHANNEL_RELIABLE PriorityImplementation specific Reliability ParameterN/A Label Length0 Protocol Length4 Label Protocol”CLUE”

RTCWED DATA CHANNEL PROTOCOL: DATA_CHANNEL_ACK | Msg Type |

DATA_CHANNEL_ACK: CLUE USAGE Header FieldCLUE Usage Value Message Type0x02 (Not CLUE specific)

RTCWEB DATA CHANNEL FOR CLUE ESTABLISHMENT NEGOTIATE/ESTABLISH SCTP CONNECTION OPEN RTCWEB DATA CHANNEL INITIATE CLUE MESSAGE EXCHANGE

NEGOTIATE/ESTABLISH DTLS/SCTP CONNECTION SDP OFFER: m=application DTLS/SCTP 1000 c=IN IP a=sctpmap:1000 webrtc-datachannel 1 a=setup:actpass a=connection:new SDP ANSWER: m=application DTLS/SCTP 2000 c=IN IP a=sctpmap:2000 webrtc-datachannel 1 a=setup:passive a=connection:new The SDP sctpmap attribute is defined in draft-ietf-mmusic-sctp-sdp.

OPEN RTCWEB DATA CHANNEL (rtcweb data channel protocol) SCTP payload protocol identifier (PPID): 50 (WebRTC Control) DATA_CHANNEL_OPEN DATA_CHANNEL_ACK DATA_CHANNEL_OPEN DATA_CHANNEL_ACK It should not matter in which order the CLUE entities send the DATA_CHANNEL_OPEN messages, but we may want to specify some rules.

CLUE ON RTCWEB DATA CHANNEL (CLUE protocol) SCTP payload protocol identifier (PPID): 51 (DOMString Last) CLUE ADVERTISEMENT/CONFIGURE etc etc etc The CLUE protocol details are outside the scope of this presentation.

REMOVAL OF DTLS CONNECTION SDP OFFER: m=application DTLS/SCTP 0 c=IN IP SDP ANSWER: m=application DTLS/SCTP 0 c=IN IP

REMOVAL OF INDIVIDUAL SCTP ASSOCIATIONS AND USAGES PENDING ( sent to MMUSIC for clarification)

THE END THANK YOU FOR LISTENING!