Internet Engineering Task Force (IETF) A. Ford
Request for Comments: 6182 Roke Manor Research
Category: Informational C. Raiciu
ISSN: 2070-1721 M. Handley
University College London
S. Barre
Universite catholique de Louvain
J. Iyengar
Franklin and Marshall College
March 2011
Architectural Guidelines for Multipath TCP Development
Abstract
Hosts are often connected by multiple paths, but TCP restricts
communications to a single path per transport connection. Resource
usage within the network would be more efficient were these multiple
paths able to be used concurrently. This should enhance user
experience through improved resilience to network failure and higher
throughput.
This document outlines architectural guidelines for the development
of a Multipath Transport Protocol, with references to how these
architectural components come together in the development of a
Multipath TCP (MPTCP). This document lists certain high-level design
decisions that provide foundations for the design of the MPTCP
protocol, based upon these architectural requirements.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6182.
Ford, et al. Informational [Page 1]RFC 6182 MPTCP Architecture March 2011Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Ford, et al. Informational [Page 2]RFC 6182 MPTCP Architecture March 2011Table of Contents
1. Introduction ....................................................4
1.1. Requirements Language ......................................5
1.2. Terminology ................................................5
1.3. Reference Scenario .........................................6
2. Goals ...........................................................6
2.1. Functional Goals ...........................................6
2.2. Compatibility Goals ........................................7
2.2.1. Application Compatibility ...........................7
2.2.2. Network Compatibility ...............................8
2.2.3. Compatibility with Other Network Users .............10
2.3. Security Goals ............................................10
2.4. Related Protocols .........................................10
3. An Architectural Basis for Multipath TCP .......................11
4. A Functional Decomposition of MPTCP ............................12
5. High-Level Design Decisions ....................................14
5.1. Sequence Numbering ........................................14
5.2. Reliability and Retransmissions ...........................15
5.3. Buffers ...................................................17
5.4. Signaling .................................................18
5.5. Path Management ...........................................19
5.6. Connection Identification .................................20
datatracker.ietf.org