< draft-eastlake-fnv-04.txt		draft-eastlake-fnv-05.txt >
	Network Working Group Glenn Fowler		Network Working Group Glenn Fowler
	INTERNET-DRAFT AT&T Labs Research		INTERNET-DRAFT AT&T Labs Research
	Intended Status: Informational Landon Curt Noll		Intended Status: Informational Landon Curt Noll
	Cisco Systems		Cisco Systems
	Kiem-Phong Vo		Kiem-Phong Vo
	AT&T Labs Research		AT&T Labs Research
	Donald Eastlake		Donald Eastlake
	Huawei Technologies		Huawei Technologies
	Expires: March 23, 2013 September 24, 2012		Expires: October 5, 2013 April 6, 2013
	The FNV Non-Cryptographic Hash Algorithm		The FNV Non-Cryptographic Hash Algorithm
	<draft-eastlake-fnv-04.txt>		<draft-eastlake-fnv-05.txt>
	Abstract		Abstract
	FNV (Fowler/Noll/Vo) is a fast, non-cryptographic hash algorithm with		FNV (Fowler/Noll/Vo) is a fast, non-cryptographic hash algorithm with
	good dispersion. The purpose of this document is to make information		good dispersion. The purpose of this document is to make information
	on FNV and open source code performing FNV conveniently available to		on FNV and open source code performing FNV conveniently available to
	the Internet community.		the Internet community.
	Status of This Memo		Status of This Memo
	skipping to change at page 2, line 37 ¶		skipping to change at page 2, line 37 ¶
	7. IANA Considerations....................................11		7. IANA Considerations....................................11
	8. Acknowledgements.......................................11		8. Acknowledgements.......................................11
	9. References.............................................12		9. References.............................................12
	9.1 Normative References..................................12		9.1 Normative References..................................12
	9.2 Informative References................................12		9.2 Informative References................................12
	Appendix A: Work Comparison with SHA-1....................13		Appendix A: Work Comparison with SHA-1....................13
	Appendix B: Previous IETF Reference to FNV................14		Appendix B: Previous IETF Reference to FNV................14
	Appendix C: A Few Test Vectors............................15		Appendix C: A Few Test Vectors............................15
	Appendix Z: Change Summary................................16		Appendix Z: Change Summary................................16
			Author's Address..........................................18
	INTERNET-DRAFT FNV		INTERNET-DRAFT FNV
	1. Introduction		1. Introduction
	The FNV hash algorithm is based on an idea sent as reviewer comments		The FNV hash algorithm is based on an idea sent as reviewer comments
	to the [IEEE] POSIX P1003.2 committee by Glenn Fowler and Phong Vo in		to the [IEEE] POSIX P1003.2 committee by Glenn Fowler and Phong Vo in
	1991. In a subsequent ballot round Landon Curt Noll suggested an		1991. In a subsequent ballot round Landon Curt Noll suggested an
	improvement on their algorithm. Some people tried this hash and found		improvement on their algorithm. Some people tried this hash and found
	that it worked rather well. In an EMail message to Landon, they named		that it worked rather well. In an EMail message to Landon, they named
	it the "Fowler/Noll/Vo" or FNV hash. [FNV]		it the "Fowler/Noll/Vo" or FNV hash. [FNV]
	FNV hashes are designed to be fast while maintaining a low collision		FNV hashes are designed to be fast while maintaining a low collision
	rate. The high dispersion of the FNV hashes makes them well suited		rate. The high dispersion of the FNV hashes makes them well suited
	for hashing nearly identical strings such as URLs, hostnames,		for hashing nearly identical strings such as URLs, hostnames,
	filenames, text, IP addresses, etc. Their speed allows one to quickly		filenames, text, IP addresses, etc. Their speed allows one to quickly
	hash lots of data while maintaining a reasonably low collision rate.		hash lots of data while maintaining a reasonably low collision rate.
	However, they are generally not suitable for cryptographic use. (See		However, they are generally not suitable for cryptographic use. (See
	Section 6.1.)		Section 6.1.)
	The FNV hash is widely used, for example in DNS servers, database		The FNV hash is widely used, for example in DNS servers, the Twitter
	indexing hashes, major web search / indexing engines, netnews history		service, database indexing hashes, major web search / indexing
	file Message-ID lookup functions, anti-spam filters, a spellchecker		engines, netnews history file Message-ID lookup functions, anti-spam
	programmed in Ada 95, flatassembler's open source x86 assembler -		filters, a spellchecker programmed in Ada 95, flatassembler's open
	user-defined symbol hashtree, non-cryptographic file fingerprints,		source x86 assembler - user-defined symbol hashtree, non-
	computing Unique IDs in DASM (DTN Applications for Symbian Mobile-		cryptographic file fingerprints, computing Unique IDs in DASM (DTN
	phones), Microsoft's hash_map implementation for VC++ 2005, the		Applications for Symbian Mobile-phones), Microsoft's hash_map
	realpath cache in PHP 5.x (php-5.2.3/TSRM/tsrm_virtual_cwd.c), and		implementation for VC++ 2005, the realpath cache in PHP 5.x
	many other uses.		(php-5.2.3/TSRM/tsrm_virtual_cwd.c), and many other uses.
			A study has recommended FNV in connetion with the IPv6 Flow Label
			field [IPv6flow].
	FNV hash algorithms and source code have been released into the		FNV hash algorithms and source code have been released into the
	public domain. The authors of the FNV algorithm took deliberate steps		public domain. The authors of the FNV algorithm took deliberate steps
	to disclose the algorithm in a public forum soon after it was		to disclose the algorithm in a public forum soon after it was
	invented. More than a year passed after this public disclosure and		invented. More than a year passed after this public disclosure and
	the authors deliberately took no steps to patent the FNV algorithm.		the authors deliberately took no steps to patent the FNV algorithm.
	Therefore, it is safe to say that the FNV authors have no patent		Therefore, it is safe to say that the FNV authors have no patent
	claims on the FNV algorithm as published.		claims on the FNV algorithm as published.
	If you use an FNV function in an application, you are kindly		If you use an FNV function in an application, you are kindly
	skipping to change at page 12, line 26 ¶		skipping to change at page 12, line 26 ¶
	has been replaced by newer versions with slight modifications,		has been replaced by newer versions with slight modifications,
	but the 1968 version remains definitive for the Internet.		but the 1968 version remains definitive for the Internet.
	9.2 Informative References		9.2 Informative References
	[FNV] - FNV web site:		[FNV] - FNV web site:
	http://www.isthe.com/chongo/tech/comp/fnv/index.html		http://www.isthe.com/chongo/tech/comp/fnv/index.html
	[IEEE] - http://www.ieee.org		[IEEE] - http://www.ieee.org
			[IPv6flow] - https://researchspace.auckland.ac.nz/bitstream/handle/
			2292/13240/flowhashRep.pdf
	[RFC3174] - Eastlake 3rd, D. and P. Jones, "US Secure Hash Algorithm		[RFC3174] - Eastlake 3rd, D. and P. Jones, "US Secure Hash Algorithm
	1 (SHA1)", RFC 3174, September 2001.		1 (SHA1)", RFC 3174, September 2001.
	[RFC6194] - Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security		[RFC6194] - Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security
	Considerations for the SHA-0 and SHA-1 Message-Digest		Considerations for the SHA-0 and SHA-1 Message-Digest
	Algorithms", RFC 6194, March 2011.		Algorithms", RFC 6194, March 2011.
	[RFC6234] - Eastlake 3rd, D. and T. Hansen, "US Secure Hash		[RFC6234] - Eastlake 3rd, D. and T. Hansen, "US Secure Hash
	Algorithms (SHA and SHA-based HMAC and HKDF)", RFC 6234, May		Algorithms (SHA and SHA-based HMAC and HKDF)", RFC 6234, May
	2011.		2011.
	skipping to change at page 18, line 5 ¶		skipping to change at page 17, line 11 ¶
	ASCII standard.		ASCII standard.
	2. Minor addition to Section 6, point 3.		2. Minor addition to Section 6, point 3.
	INTERNET-DRAFT FNV		INTERNET-DRAFT FNV
	3. Update dates and version number.		3. Update dates and version number.
	4. Minor editing changes.		4. Minor editing changes.
			From -04 to -05
			1. Add Twitter as a use example and IPv6 flow hash study reference.
			2. Update dates and version number.
	INTERNET-DRAFT FNV		INTERNET-DRAFT FNV
	Author's Address		Author's Address
	Glenn Fowler		Glenn Fowler
	AT&T Labs Research		AT&T Labs Research
	180 Park Avenue		180 Park Avenue
	Florham Park, NJ 07932 USA		Florham Park, NJ 07932 USA
	Email: gsf@research.att.com		Email: gsf@research.att.com
	skipping to change at page 19, line 9 ¶		skipping to change at page 19, line 9 ¶
	155 Beaver Street		155 Beaver Street
	Milford, MA 01757 USA		Milford, MA 01757 USA
	Telephone: +1-508-333-2270		Telephone: +1-508-333-2270
	EMail: d3e3e3@gmail.com		EMail: d3e3e3@gmail.com
	INTERNET-DRAFT FNV		INTERNET-DRAFT FNV
	Copyright, Disclaimer, and Additional IPR Provisions		Copyright, Disclaimer, and Additional IPR Provisions
	Copyright (c) 2012 IETF Trust and the persons identified as the		Copyright (c) 2013 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(http://trustee.ietf.org/license-info) in effect on the date of		(http://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	carefully, as they describe your rights and restrictions with respect		carefully, as they describe your rights and restrictions with respect
	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
	include Simplified BSD License text as described in Section 4.e of		include Simplified BSD License text as described in Section 4.e of
	the Trust Legal Provisions and are provided without warranty as		the Trust Legal Provisions and are provided without warranty as
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