Network Working Group R. Stewart
Internet-Draft Adara Networks
Intended status: BCP M. Tuexen
Expires: August 29, 2013 I. Ruengeler
Muenster Univ. of Appl. Sciences
February 25, 2013
Stream Control Transmission Protocol (SCTP) Network Address Translation
draft-ietf-behave-sctpnat-08.txt
Abstract
Stream Control Transmission Protocol [RFC4960] provides a reliable
communications channel between two end-hosts in many ways similar to
TCP [RFC0793]. With the widespread deployment of Network Address
Translators (NAT), specialized code has been added to NAT for TCP
that allows multiple hosts to reside behind a NAT and yet use only a
single globally unique IPv4 address, even when two hosts (behind a
NAT) choose the same port numbers for their connection. This
additional code is sometimes classified as Network Address and Port
Translation or NAPT. To date, specialized code for SCTP has NOT yet
been added to most NATs so that only pure NAT is available. The end
result of this is that only one SCTP capable host can be behind a
NAT.
This document describes an SCTP specific variant of NAT which
provides similar features of NAPT in the single point and multi-point
traversal scenario.
Status of this Memo
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This Internet-Draft will expire on August 29, 2013.
Copyright Notice
Stewart, et al. Expires August 29, 2013 [Page 1]
Internet-Draft SCTP NAT February 2013
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. SCTP NAT Traversal Scenarios . . . . . . . . . . . . . . . . . 4
4.1. Single Point Traversal . . . . . . . . . . . . . . . . . . 4
4.2. Multi Point Traversal . . . . . . . . . . . . . . . . . . 5
5. Limitations of Classical NAPT for SCTP . . . . . . . . . . . . 6
6. The SCTP Specific Variant of NAT . . . . . . . . . . . . . . . 6
7. NAT to SCTP . . . . . . . . . . . . . . . . . . . . . . . . . 11
8. Handling of Fragmented SCTP Packets . . . . . . . . . . . . . 11
9. Various Examples of NAT Traversals . . . . . . . . . . . . . . 11
9.1. Single-homed Client to Single-homed Server . . . . . . . . 11
9.2. Single-homed Client to Multi-homed Server . . . . . . . . 13
9.3. Multihomed Client and Server . . . . . . . . . . . . . . . 15
9.4. NAT Loses Its State . . . . . . . . . . . . . . . . . . . 19
9.5. Peer-to-Peer Communication . . . . . . . . . . . . . . . . 21
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
11. Security Considerations . . . . . . . . . . . . . . . . . . . 25
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 26
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 26
13.1. Normative References . . . . . . . . . . . . . . . . . . . 26
13.2. Informative References . . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26
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