1 IETF 64th meeting, Vancouver, Canada GIST over SCTP Xiaoming Fu Christian Dickmann Jon Crowcroft

2 IETF 64th meeting, Vancouver, Canada Overview Motivation GIST over SCTP Implementation status Open issues Next steps

3 IETF 64th meeting, Vancouver, Canada Motivation Current NTLP/GIST spec defines a flexible transport framework which (theoretically) allows any type of transport mechanism Currently only support UDP, TCP and recently TLS over TCP SCTP initially defined as a signaling transport protocol possesses many properties required by signaling transport It should be possible to extend GIST to support SCTP as transport GIST over SCTP: Describes the considerations of extending GIST to support Basic SCTP features: stream-based, multi-homing, etc Considerations for partial reliability, TLS over SCTP

4 IETF 64th meeting, Vancouver, Canada GIST Protocol Negotiation Overview (per GIST draft) Stack-Proposal: sequence of Profiles Profile: stack of Protocol-Layers Protocol-Layer: protocol name and security / stack-configuration- data Add new setup mechanisms by defining new protocol-layers Querying NodeResponding Node GIST-Query: Stack-Proposal-Q (fixed for interface and NSLPID) Node-Addressing-Information (parameters for possible protocols) GIST-Response: Stack-Proposal-R (fixed for interface and NSLPID) Node-Addressing-Information’ (updated object from query) GIST-Confirm (in C-mode): Stack-Proposal-R (echoed)

5 IETF 64th meeting, Vancouver, Canada GIST over SCTP GIST stack proposal and its negotiation: Add “SCTP” as a new transport protocol ID Define Stack-Configuration-Data for “SCTP” Suggest rules to support multi-homing, PR-SCTP, TLS/SCTP This proposal mainly discusses the necessary changes to GIST in order to use SCPT as transport. Potentially, access router discovery can be also based on GIST

6 IETF 64th meeting, Vancouver, Canada Implementation status All basic SCTP support: implemented in GIST release ~TCP, with an exception when session number becomes very huge (40k) SCTP expert told me this can be due to the Linux SCTP implementation PR-SCTP and TLS/SCTP support: TBD

7 IETF 64th meeting, Vancouver, Canada Open Issues How to exactly support multi-homing Host multihoming is easy Per neighbor-pair multihoming needs further study

8 IETF 64th meeting, Vancouver, Canada Next Steps Is this work useful? Should it be accepted as a WG item?