1 IETF 64th meeting, Vancouver, Canada

GIST over SCTP<draft-fu-nsis-ntlp-sctp-00.txt>

Xiaoming Fu

Christian Dickmann

Jon Crowcroft

2 IETF 64th meeting, Vancouver, Canada

Overview

• Motivation

• GIST over SCTP

• Implementation status

• Open issues

• Next steps

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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

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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 Node

Responding 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)

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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

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Implementation status

• All basic SCTP support: implemented in GIST release 0.2.0

• ~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

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Open Issues

• How to exactly support multi-homing

• Host multihoming is easy

• Per neighbor-pair multihoming needs further study

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Next Steps

• Is this work useful?

• Should it be accepted as a WG item?