< draft-ietf-ipsecme-chacha20-poly1305-03.txt		draft-ietf-ipsecme-chacha20-poly1305-04.txt >
	Network Working Group Y. Nir		Network Working Group Y. Nir
	Internet-Draft Check Point		Internet-Draft Check Point
	Intended status: Standards Track April 25, 2015		Intended status: Standards Track April 26, 2015
	Expires: October 27, 2015		Expires: October 28, 2015
	ChaCha20, Poly1305 and their use in IKE & IPsec		ChaCha20, Poly1305 and their use in IKE & IPsec
	draft-ietf-ipsecme-chacha20-poly1305-03		draft-ietf-ipsecme-chacha20-poly1305-04
	Abstract		Abstract
	This document describes the use of the ChaCha20 stream cipher along		This document describes the use of the ChaCha20 stream cipher along
	with the Poly1305 authenticator, combined into an AEAD algorithm for		with the Poly1305 authenticator, combined into an AEAD algorithm for
	the Internet Key Exchange protocol (IKEv2) and for IPsec.		the Internet Key Exchange protocol (IKEv2) and for IPsec.
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	skipping to change at page 1, line 32 ¶		skipping to change at page 1, line 32 ¶
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
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	This Internet-Draft will expire on October 27, 2015.		This Internet-Draft will expire on October 28, 2015.
	Copyright Notice		Copyright Notice
	Copyright (c) 2015 IETF Trust and the persons identified as the		Copyright (c) 2015 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
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	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
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	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
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	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
	1.1. Conventions Used in This Document . . . . . . . . . . . . 2		1.1. Conventions Used in This Document . . . . . . . . . . . . 3
	2. ChaCha20 & Poly1305 for ESP . . . . . . . . . . . . . . . . . 3		2. ChaCha20 & Poly1305 for ESP . . . . . . . . . . . . . . . . . 3
	2.1. AAD Construction . . . . . . . . . . . . . . . . . . . . 4		2.1. AAD Construction . . . . . . . . . . . . . . . . . . . . 4
	3. Use in IKEv2 . . . . . . . . . . . . . . . . . . . . . . . . 4		3. Use in IKEv2 . . . . . . . . . . . . . . . . . . . . . . . . 4
	4. Negotiation in IKEv2 . . . . . . . . . . . . . . . . . . . . 4		4. Negotiation in IKEv2 . . . . . . . . . . . . . . . . . . . . 5
	5. Security Considerations . . . . . . . . . . . . . . . . . . . 5		5. Security Considerations . . . . . . . . . . . . . . . . . . . 5
	6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5		6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
	7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5		7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
	8. References . . . . . . . . . . . . . . . . . . . . . . . . . 5		8. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
	8.1. Normative References . . . . . . . . . . . . . . . . . . 5		8.1. Normative References . . . . . . . . . . . . . . . . . . 6
	8.2. Informative References . . . . . . . . . . . . . . . . . 6		8.2. Informative References . . . . . . . . . . . . . . . . . 6
	Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6		Appendix A. ESP Example . . . . . . . . . . . . . . . . . . . . 7
			Appendix B. IKEv2 Example . . . . . . . . . . . . . . . . . . . 9
			Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11
	1. Introduction		1. Introduction
	The Advanced Encryption Standard (AES - [FIPS-197]) has become the		The Advanced Encryption Standard (AES - [FIPS-197]) has become the
	gold standard in encryption. Its efficient design, wide		gold standard in encryption. Its efficient design, wide
	implementation, and hardware support allow for high performance in		implementation, and hardware support allow for high performance in
	many areas, including IPsec VPNs. On most modern platforms, AES is		many areas, including IPsec VPNs. On most modern platforms, AES is
	anywhere from 4x to 10x as fast as the previous most-used cipher,		anywhere from 4x to 10x as fast as the previous most-used cipher,
	3-key Data Encryption Standard (3DES - [SP800-67]). 3DES also has a		3-key Data Encryption Standard (3DES - [SP800-67]). 3DES also has a
	64-bit block, which means that the amount of data that can be		64-bit block, which means that the amount of data that can be
	skipping to change at page 3, line 17 ¶		skipping to change at page 3, line 23 ¶
	AEAD_CHACHA20_POLY1305 is a combined mode algorithm, or AEAD. The		AEAD_CHACHA20_POLY1305 is a combined mode algorithm, or AEAD. The
	construction follows the AEAD construction in section 2.8 of		construction follows the AEAD construction in section 2.8 of
	[chacha_poly]:		[chacha_poly]:
	o The Initialization Vector (IV) is 64-bit, and is used as part of		o The Initialization Vector (IV) is 64-bit, and is used as part of
	the nonce. The IV MUST be unique for each invocation for a		the nonce. The IV MUST be unique for each invocation for a
	particular SA but does not need to be unpredictable. The use of a		particular SA but does not need to be unpredictable. The use of a
	counter or a linear feedback shift register (LFSR) is RECOMMENDED.		counter or a linear feedback shift register (LFSR) is RECOMMENDED.
	o A 32-bit Salt is prepended to the 64-bit IV to form the 96-bit		o A 32-bit Salt is prepended to the 64-bit IV to form the 96-bit
	nonce. The salt is fixed per SA and it is not transmitted as part		nonce. The salt is fixed per SA and it is not transmitted as part
	of the ESP packet..		of the ESP packet.
	o The encryption key is 256-bit.		o The encryption key is 256-bit.
	o The Internet Key Exchange protocol generates a bitstring called		o The Internet Key Exchange protocol generates a bitstring called
	KEYMAT using a pseudo-random function (PRF). That KEYMAT is		KEYMAT using a pseudo-random function (PRF). That KEYMAT is
	divided into keys for encryption, message authentication and		divided into keys for encryption, message authentication and
	whatever else is needed. For the ChaCha20-poly1305 algorithm, 256		whatever else is needed. The KEYMAT requested for each
	bits are used for the key, and a subsequent 32 bits are used for		ChaCha20-Poly1305 key is 36 octets. The first 32 octets are the
	the Salt.		256-bit ChaCha20 key, and the remaining four octets are used as
			the Salt value in the nonce.
	The ChaCha20 encryption algorithm requires the following parameters:		The ChaCha20 encryption algorithm requires the following parameters:
	a 256-bit key, a 96-bit nonce, and a 32-bit initial block counter.		a 256-bit key, a 96-bit nonce, and a 32-bit initial block counter.
	For ESP we set these as follows:		For ESP we set these as follows:
	o The key is set as mentioned above.		o The key is set as mentioned above.
	o The 96-bit nonce is formed from a concatenation of the 32-bit Salt		o The 96-bit nonce is formed from a concatenation of the 32-bit Salt
	and the 64-bit IV, as described above.		and the 64-bit IV, as described above.
	o The Initial Block Counter is set to one (1). The reason that one		o The Initial Block Counter is set to one (1). The reason that one
	is used for the initial counter rather than zero is that zero is		is used for the initial counter rather than zero is that zero is
	reserved for generating the one-time Poly1305 key (see below)		reserved for generating the one-time Poly1305 key (see below)
	As the ChaCha20 block function is not applied directly to the		As the ChaCha20 block function is not applied directly to the
	plaintext, no padding should be necessary. However, in keeping with		plaintext, no padding should be necessary. However, in keeping with
	the specification in RFC 4303, the ESP does have padding, so as to		the specification in RFC 4303, the plaintext always has a pad length
	align the buffer to an integral multiple of 4 octets.		octet and may require padding bytes so as to align the buffer to an
			integral multiple of 4 octets.
	The same key and nonce, along with a block counter of zero are passed		The same key and nonce, along with a block counter of zero are passed
	to the ChaCha20 block function, and the top 256 bits of the result		to the ChaCha20 block function, and the top 256 bits of the result
	are used as the Poly1305 key. The nonce passed to the block function		are used as the Poly1305 key. The nonce passed to the block function
	here is the same nonce that is used in ChaCha20, including the 32-bit		here is the same nonce that is used in ChaCha20, including the 32-bit
	Salt, and the key passed is the same as the encryption key.		Salt, and the key passed is the same as the encryption key.
	Finally, the Poly1305 function is run on the data to be		Finally, the Poly1305 function is run on the data to be
	authenticated, which is, as specified in section 2.8 of [chacha_poly]		authenticated, which is, as specified in section 2.8 of [chacha_poly]
	a concatenation of the following in the below order:		a concatenation of the following in the below order:
	skipping to change at page 4, line 38 ¶		skipping to change at page 4, line 45 ¶
	For SAs with ESN the AAD is 12 bytes: 4-byte SPI followed by an		For SAs with ESN the AAD is 12 bytes: 4-byte SPI followed by an
	8-byte sequence number as a 64-bit network order integer.		8-byte sequence number as a 64-bit network order integer.
	3. Use in IKEv2		3. Use in IKEv2
	AEAD algorithms can be used in IKE, as described in [RFC5282]. More		AEAD algorithms can be used in IKE, as described in [RFC5282]. More
	specifically:		specifically:
	o The Encrypted Payload is as described in section 3 of that		o The Encrypted Payload is as described in section 3 of that
	document.		document.
			o The ChaCha20-Poly1305 keying material is derived from KEYMAT as
			for ESP: 36 octets are requested, of which the first 32 form the
			key and the last 4 form the salt.
	o The IV is 64 bits, as described in Section 2.		o The IV is 64 bits, as described in Section 2.
	o The AAD is as described in section 5.1 of RFC 5282, so it's 32		o The AAD is as described in section 5.1 of RFC 5282, so it's 32
	bytes (28 for the IKEv2 header + 4 bytes for the encrypted payload		bytes (28 for the IKEv2 header + 4 bytes for the encrypted payload
	header) assuming no unencrypted payloads.		header) assuming no unencrypted payloads.
	4. Negotiation in IKEv2		4. Negotiation in IKEv2
	When negotiating the ChaCha20-Poly1305 algorithm for use in IKE or		When negotiating the ChaCha20-Poly1305 algorithm for use in IKE or
	IPsec, the value xxx (TBA by IANA) should be used in the transform		IPsec, the value xxx (TBA by IANA) should be used in the transform
	substructure of the SA payload as the ENCR (type 1) transform ID. As		substructure of the SA payload as the ENCR (type 1) transform ID. As
	skipping to change at page 6, line 32 ¶		skipping to change at page 6, line 42 ¶
	Relations among notions and analysis of the generic		Relations among notions and analysis of the generic
	composition paradigm", 2000,		composition paradigm", 2000,
	<http://cseweb.ucsd.edu/~mihir/papers/oem.html>.		<http://cseweb.ucsd.edu/~mihir/papers/oem.html>.
	[FIPS-197]		[FIPS-197]
	National Institute of Standards and Technology, "Advanced		National Institute of Standards and Technology, "Advanced
	Encryption Standard (AES)", FIPS PUB 197, November 2001,		Encryption Standard (AES)", FIPS PUB 197, November 2001,
	<http://csrc.nist.gov/publications/fips/fips197/		<http://csrc.nist.gov/publications/fips/fips197/
	fips-197.pdf>.		fips-197.pdf>.
			[RFC1761] Callaghan, B. and R. Gilligan, "Snoop Version 2 Packet
			Capture File Format", RFC 1761, February 1995,
			<https://tools.ietf.org/html/rfc1761>.
	[RFC4106] Viega, J. and D. McGrew, "The Use of Galois/Counter Mode		[RFC4106] Viega, J. and D. McGrew, "The Use of Galois/Counter Mode
	(GCM) in IPsec Encapsulating Security Payload (ESP)", RFC		(GCM) in IPsec Encapsulating Security Payload (ESP)", RFC
	4106, June 2005.		4106, June 2005.
	[SP800-67]		[SP800-67]
	National Institute of Standards and Technology,		National Institute of Standards and Technology,
	"Recommendation for the Triple Data Encryption Algorithm		"Recommendation for the Triple Data Encryption Algorithm
	(TDEA) Block Cipher", FIPS SP800-67, January 2012,		(TDEA) Block Cipher", FIPS SP800-67, January 2012,
	<http://csrc.nist.gov/publications/nistpubs/800-67-Rev1/		<http://csrc.nist.gov/publications/nistpubs/800-67-Rev1/
	SP-800-67-Rev1.pdf>.		SP-800-67-Rev1.pdf>.
	[standby-cipher]		[standby-cipher]
	McGrew, D., Grieco, A., and Y. Sheffer, "Selection of		McGrew, D., Grieco, A., and Y. Sheffer, "Selection of
	Future Cryptographic Standards", draft-mcgrew-standby-		Future Cryptographic Standards", draft-mcgrew-standby-
	cipher (work in progress), January 2013.		cipher (work in progress), January 2013.
			Appendix A. ESP Example
			For this example, we will use a tunnel-mode ESP SA using the
			ChaCha20-Poly1305 algorithm. The keying material is as follows:
			KEYMAT:
			000 80 81 82 83 84 85 86 87 88 89 8a 8b 8c 8d 8e 8f ................
			016 90 91 92 93 94 95 96 97 98 99 9a 9b 9c 9d 9e 9f ................
			032 a0 a1 a2 a3 ....
			Obviously not a great PRF. The first 32 octets are the key and the
			final four octets (0xa0 0xa1 0xa2 0xa3) are the salt. For the
			packet, we will use an ICMP packet from 198.51.100.5 to 192.0.2.5:
			Source Packet:
			000 45 00 00 54 a6 f2 00 00 40 01 e7 78 c6 33 64 05 E..T....@..x.3d.
			016 c0 00 02 05 08 00 5b 7a 3a 08 00 00 55 3b ec 10 ......[z:...U;..
			032 00 07 36 27 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 ..6'............
			048 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 ............ !"#
			064 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 $%&'()*+,-./0123
			080 34 35 36 37 4567
			The SA details are as follows:
			o The key and Salt are as above.
			o The SPI is 0x01 0x02 0x03 0x04.
			o The next sequence number is 5; ESN is not enabled.
			o The gateway IP address for this side is 203.0.113.153; The peer
			address is 203.0.113.5.
			o NAT was not detected.
			The 64-bit IV is 0x10 0x11 0x12 0x13 0x14 0x15 0x16 0x17. Putting
			together the salt and IV we get the nonce:
			The nonce:
			000 a0 a1 a2 a3 10 11 12 13 14 15 16 17 ............
			The plaintext to encrypt consists of the source IP packet plus the
			padding:
			Plaintext (includes padding and pad length):
			000 45 00 00 54 a6 f2 00 00 40 01 e7 78 c6 33 64 05 E..T....@..x.3d.
			016 c0 00 02 05 08 00 5b 7a 3a 08 00 00 55 3b ec 10 ......[z:...U;..
			032 00 07 36 27 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 ..6'............
			048 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 ............ !"#
			064 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 $%&'()*+,-./0123
			080 34 35 36 37 01 02 03 03 4567....
			With the key, nonce and plaintext available, we can call the ChaCha20
			function and encrypt the packet, producing the ciphertext:
			Ciphertext:
			000 24 03 94 28 b9 7f 41 7e 3c 13 75 3a 4f 05 08 7b $..(..A~<.u:O..{
			016 67 c3 52 e6 a7 fa b1 b9 82 d4 66 ef 40 7a e5 c6 g.R.......f.@z..
			032 14 ee 80 99 d5 28 44 eb 61 aa 95 df ab 4c 02 f7 .....(D.a....L..
			048 2a a7 1e 7c 4c 4f 64 c9 be fe 2f ac c6 38 e8 f3 *..|LOd.../..8..
			064 cb ec 16 3f ac 46 9b 50 27 73 f6 fb 94 e6 64 da ...?.F.P's....d.
			080 91 65 b8 28 29 f6 40 e7 .e.().@.
			To calculate the tag, we need a one-time Poly1305 key, which we
			calculate by calling the ChaCha20 function again with the same key
			and nonce, but a block count of zero.
			Poly1305 one-time key:
			000 af 1f 41 2c c1 15 ad ce 5e 4d 0e 29 d5 c1 30 bf ..A,....^M.)..0.
			016 46 31 21 0e 0f ef 74 31 c0 45 4f e7 0f d7 c2 d1 F1!...t1.EO.....
			The AAD is constructed by concatenating the SPI to the sequence
			number:
			000 01 02 03 04 00 00 00 05 ........
			The input to the Poly1305 function is constructed by concatenating
			and padding the AAD and ciphertext:
			Poly1305 Input:
			000 01 02 03 04 00 00 00 05 00 00 00 00 00 00 00 00 ................
			016 24 03 94 28 b9 7f 41 7e 3c 13 75 3a 4f 05 08 7b $..(..A~<.u:O..{
			032 67 c3 52 e6 a7 fa b1 b9 82 d4 66 ef 40 7a e5 c6 g.R.......f.@z..
			048 14 ee 80 99 d5 28 44 eb 61 aa 95 df ab 4c 02 f7 .....(D.a....L..
			064 2a a7 1e 7c 4c 4f 64 c9 be fe 2f ac c6 38 e8 f3 *..|LOd.../..8..
			080 cb ec 16 3f ac 46 9b 50 27 73 f6 fb 94 e6 64 da ...?.F.P's....d.
			096 91 65 b8 28 29 f6 40 e7 00 00 00 00 00 00 00 00 .e.().@.........
			112 08 00 00 00 00 00 00 00 58 00 00 00 00 00 00 00 ........X.......
			The resulting tag is:
			Tag:
			000 f0 5f ff a1 a0 cc cd de 88 a3 e8 9a 21 2b 18 ba ._..........!+..
			Putting it all together, the resulting packet is as follows:
			ESP packet:
			000 45 00 00 8c 23 45 00 00 40 32 de 5b cb 00 71 99 E...#E..@2.[..q.
			016 cb 00 71 05 01 02 03 04 00 00 00 05 10 11 12 13 ..q.............
			032 14 15 16 17 24 03 94 28 b9 7f 41 7e 3c 13 75 3a ....$..(..A~<.u:
			048 4f 05 08 7b 67 c3 52 e6 a7 fa b1 b9 82 d4 66 ef O..{g.R.......f.
			064 40 7a e5 c6 14 ee 80 99 d5 28 44 eb 61 aa 95 df @z.......(D.a...
			080 ab 4c 02 f7 2a a7 1e 7c 4c 4f 64 c9 be fe 2f ac .L..*..|LOd.../.
			096 c6 38 e8 f3 cb ec 16 3f ac 46 9b 50 27 73 f6 fb .8.....?.F.P's..
			112 94 e6 64 da 91 65 b8 28 29 f6 40 e7 f0 5f ff a1 ..d..e.().@.._..
			128 a0 cc cd de 88 a3 e8 9a 21 2b 18 ba ........!+..
			Appendix B. IKEv2 Example
			For the IKEv2 example, we'll use the following:
			o The key is 0x80..0x9f, the same as in Appendix A.
			o The Salt is 0xa0 0xa1 0xa2 0xa3.
			o The IV will also be the same as in the previous example. The fact
			that the IV and Salt are both the same means that the nonce is
			also the same.
			o Because the key and nonce are the same, so is the one-time
			Poly1305 key.
			o The packet with be an Informational request carrying a single
			payload: A Notify payload with type SET_WINDOW_SIZE, setting the
			window size to 10.
			o iSPI = 0xc0 0xc1 0xc2 0xc3 0xc4 0xc5 0xc6 0xc7.
			o rSPI = 0xd0 0xd1 0xd2 0xd3 0xd4 0xd5 0xd6 0xd7.
			o Message ID shall be 9.
			The Notify Payload:
			000 00 00 00 0c 00 00 40 01 00 00 00 0a ......@.....
			<t> Padding as required by RFC 7296:</t>
			<t><figure>
			<artwork><![CDATA[
			Plaintext (includes padding and pad length):
			000 00 00 00 0c 00 00 40 01 00 00 00 0a 01 02 03 03 ......@.........
			Ciphertext:
			000 61 03 94 70 1f 8d 01 7f 7c 12 92 48 88 34 6f 7d a..p....|..H.4o}
			The AAD is constructed by appending the IKE header to the encrypted
			payload header. Note that the length field in the IKE header and the
			length field in the encrypted payload header have to be calculated
			before constructing the AAD:
			AAD:
			000 c0 c1 c2 c3 c4 c5 c6 c7 d0 d1 d2 d3 d4 d5 d6 d7 ................
			016 2e 20 25 00 00 00 00 09 00 00 00 48 00 00 00 2c . %........H...,
			In this case, the length of the AAD is an integral multiple of 16, so
			when constructing the input to Poly1305 there was no need for
			padding. The ciphertext is also 16 octets long, so the construction
			has no padding at all. Just 32 octets of AAD, 16 octets of
			ciphertext, and two 8-octet length fields in little-endian encoding.
			Poly1305 Input:
			000 c0 c1 c2 c3 c4 c5 c6 c7 d0 d1 d2 d3 d4 d5 d6 d7 ................
			016 2e 20 25 00 00 00 00 09 00 00 00 48 00 00 00 2c . %........H...,
			032 61 03 94 70 1f 8d 01 7f 7c 12 92 48 88 34 6f 7d a..p....|..H.4o}
			048 20 00 00 00 00 00 00 00 10 00 00 00 00 00 00 00 ...............
			Tag:
			000 92 7a e2 94 79 59 24 93 a9 aa 97 d6 cc c6 b5 b4 .z..yY$.........
			Encrypted Payload:
			000 00 00 00 2c 10 11 12 13 14 15 16 17 61 03 94 70 ...,........a..p
			016 1f 8d 01 7f 7c 12 92 48 88 34 6f 7d 92 7a e2 94 ....|..H.4o}.z..
			032 79 59 24 93 a9 aa 97 d6 cc c6 b5 b4 yY$.........
			The IKE Message:
			000 c0 c1 c2 c3 c4 c5 c6 c7 d0 d1 d2 d3 d4 d5 d6 d7 ................
			016 2e 20 25 00 00 00 00 09 00 00 00 48 00 00 00 2c . %........H...,
			032 10 11 12 13 14 15 16 17 61 03 94 70 1f 8d 01 7f ........a..p....
			048 7c 12 92 48 88 34 6f 7d 92 7a e2 94 79 59 24 93 |..H.4o}.z..yY$.
			064 a9 aa 97 d6 cc c6 b5 b4 ........
			The below file in the snoop format [RFC1761] contains three packets:
			The first is the ICMP packet from the example in the Appendix A, the
			second is the ESP packet from the same appendix, and the third is the
			IKEv2 packet from this appendix. To convert this text back into a
			file, you can use a Unix command line tools such as "openssl enc -d
			-a":
			c25vb3AAAAAAAAACAAAABAAAAGIAAABiAAAAegAAAABVPR8iAAADVdhs6fUQBHgx
			wbcpwggARQAAVKbyAABAAed4xjNkBcAAAgUIAFt6OggAAFU77BAABzYnCAkKCwwN
			Dg8QERITFBUWFxgZGhscHR4fICEiIyQlJicoKSorLC0uLzAxMjM0NTY3AAAAmgAA
			AJoAAACyAAAAAFU9HyIAAAo62Gzp9RAEeDHBtynCCABFAACMI0UAAEAy3lvLAHGZ
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	Author's Address		Author's Address
	Yoav Nir		Yoav Nir
	Check Point Software Technologies Ltd.		Check Point Software Technologies Ltd.
	5 Hasolelim st.		5 Hasolelim st.
	Tel Aviv 6789735		Tel Aviv 6789735
	Israel		Israel
	Email: ynir.ietf@gmail.com		Email: ynir.ietf@gmail.com
End of changes. 14 change blocks.
	15 lines changed or deleted		212 lines changed or added
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