RFC 6056: Recommendations for Transport-Protocol Port Randomization
In plain English — editorial summary, not part of the RFC
During the last few years, awareness has been raised about a number of "blind" attacks that can be performed against the Transmission Control Protocol (TCP) and similar protocols. The consequences of these attacks range from throughput reduction to broken connections or data corruption. These attacks rely on the attacker's ability to guess or know the five-tuple (Protocol, Source Address, Destination Address, Source Port, Destination Port) that identifies the transport protocol instance to be attacked. This document describes a number of simple and efficient methods for the selection of the client port number, such that the possibility of an attacker guessing the exact value is reduced. While this is not a replacement for cryptographic methods for protecting the transport-protocol instance, the aforementioned port selection algorithms provide improved security with very little effort and without any key management overhead. The algorithms described in this document are local policies that may be incrementally deployed and that do not violate the specifications of any of the transport protocols that may benefit from them, such as TCP, UDP, UDP-lite, Stream Control Transmission Protocol (SCTP), Datagram Congestion Control Protocol (DCCP), and RTP (provided that the RTP application explicitly signals the RTP and RTCP port numbers). This memo documents an Internet Best Current Practice.
Document record
- Document ID
- RFC6056
- Published
- January 2011
- Authors
- M. Larsen; F. Gont
- Status
- BEST CURRENT PRACTICE
- Stream
- IETF
- Area
- wit
- Pages
- 29
- Also known as
- BCP156
Topics
Related documents
Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.
- RFC 5961Improving TCP's Robustness to Blind In-Window AttacksUpdated
August 2010
- RFC 5927ICMP Attacks against TCPCurrent
July 2010
- RFC 6633Deprecation of ICMP Source Quench MessagesCurrent
May 2012
- RFC 7560Problem Statement and Requirements for Increased Accuracy in Explicit Congestion Notification (ECN) FeedbackCurrent
August 2015
- RFC 7605Recommendations on Using Assigned Transport Port NumbersCurrent
August 2015
- RFC 7661Updating TCP to Support Rate-Limited TrafficCurrent
October 2015
- RFC 7765TCP and Stream Control Transmission Protocol (SCTP) RTO RestartCurrent
February 2016
- RFC 4138Forward RTO-Recovery (F-RTO): An Algorithm for Detecting Spurious Retransmission Timeouts with TCP and the Stream Control Transmission Protocol (SCTP)Updated
August 2005
Also filed under
About this page
The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.
Last checked against the RFC Editor index on . RFCs are never revised after publication; changes are issued as new documents.
Data sources · Editorial policy · Report a correction · What is an RFC?