draft-ietf-ippm-checksum-trailer-01.txt		draft-ietf-ippm-checksum-trailer-02.txt
	Network Working Group T. Mizrahi		Network Working Group T. Mizrahi
	Internet Draft Marvell		Internet Draft Marvell
	Intended status: Informational		Intended status: Informational
	Expires: September 2015 March 9, 2015		Expires: January 2016 July 20, 2015
	UDP Checksum Complement in OWAMP and TWAMP		UDP Checksum Complement in OWAMP and TWAMP
	draft-ietf-ippm-checksum-trailer-01.txt		draft-ietf-ippm-checksum-trailer-02.txt
	Abstract		Abstract
	The One-Way Active Measurement Protocol (OWAMP) and the Two-Way		The One-Way Active Measurement Protocol (OWAMP) and the Two-Way
	Active Measurement Protocol (TWAMP) are used for performance		Active Measurement Protocol (TWAMP) are used for performance
	monitoring in IP networks. Delay measurement is performed in these		monitoring in IP networks. Delay measurement is performed in these
	protocols by using timestamped test packets. Some implementations use		protocols by using timestamped test packets. Some implementations use
	hardware-based timestamping engines that integrate the accurate		hardware-based timestamping engines that integrate the accurate
	transmission timestamp into every outgoing OWAMP/TWAMP test packet		transmission timestamp into every outgoing OWAMP/TWAMP test packet
	during transmission. Since these packets are transported over UDP,		during transmission. Since these packets are transported over UDP,
	skipping to change at page 1, line 47		skipping to change at page 1, line 47
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	The list of current Internet-Drafts can be accessed at		The list of current Internet-Drafts can be accessed at
	http://www.ietf.org/ietf/1id-abstracts.txt.		http://www.ietf.org/ietf/1id-abstracts.txt.
	The list of Internet-Draft Shadow Directories can be accessed at		The list of Internet-Draft Shadow Directories can be accessed at
	http://www.ietf.org/shadow.html.		http://www.ietf.org/shadow.html.
	This Internet-Draft will expire on September 9, 2015.		This Internet-Draft will expire on January 20, 2016.
	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.
	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
	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1. Introduction ................................................. 2		1. Introduction...................................................2
	2. Conventions used in this document ............................ 4		2. Conventions used in this document..............................4
	2.1. Terminology ............................................. 4		2.1. Terminology...............................................4
	2.2. Abbreviations ........................................... 4		2.2. Abbreviations.............................................4
	3. Using the UDP Checksum Complement in OWAMP and TWAMP ......... 5		3. Using the UDP Checksum Complement in OWAMP and TWAMP...........5
	3.1. Overview ................................................ 5		3.1. Overview..................................................5
	3.2. OWAMP / TWAMP Test Packets with Checksum Complement ..... 5		3.2. OWAMP / TWAMP Test Packets with Checksum Complement.......5
	3.2.1. Transmission of OWAMP/TWAMP with Checksum Complement 8		3.2.1. Transmission of OWAMP/TWAMP with Checksum Complement.8
	3.2.2. Intermediate Updates of OWAMP/TWAMP with Checksum		3.2.2. Intermediate Updates of OWAMP/TWAMP with Checksum
	Complement ................................................ 9		Complement..................................................9
	3.2.3. Reception of OWAMP/TWAMP with Checksum Complement .. 9		3.2.3. Reception of OWAMP/TWAMP with Checksum Complement....9
	3.3. Interoperability with Existing Implementations........... 9		3.3. Interoperability with Existing Implementations............9
	3.4. Using the Checksum Complement with or without Authentication		3.4. Using the Checksum Complement with or without Authentication
	............................................................ 9		...............................................................9
	3.4.1. Checksum Complement in Authenticated Mode........... 9		3.4.1. Checksum Complement in Authenticated Mode............9
	3.4.2. Checksum Complement in Encrypted Mode .............. 9		3.4.2. Checksum Complement in Encrypted Mode................9
	4. Security Considerations ..................................... 10		4. Security Considerations.......................................10
	5. IANA Considerations ......................................... 10		5. IANA Considerations...........................................10
	6. Acknowledgments ............................................. 11		6. Acknowledgments...............................................11
	7. References .................................................. 11		7. References....................................................11
	7.1. Normative References ................................... 11		7.1. Normative References.....................................11
	7.2. Informative References ................................. 11		7.2. Informative References...................................11
	1. Introduction		1. Introduction
	The One-Way Active Measurement Protocol ([OWAMP]) and the Two-Way		The One-Way Active Measurement Protocol ([OWAMP]) and the Two-Way
	Active Measurement Protocol ([TWAMP]) are used for performance		Active Measurement Protocol ([TWAMP]) are used for performance
	monitoring in IP networks.		monitoring in IP networks.
	Delay and delay variation are two of the metrics that OWAMP/TWAMP can		Delay and delay variation are two of the metrics that OWAMP/TWAMP can
	measure. This measurement is performed using timestamped test		measure. This measurement is performed using timestamped test
	packets.		packets.
	The accuracy of delay measurements relies on the timestamping method		The accuracy of delay measurements relies on the timestamping method
	and its implementation. In order to facilitate accurate timestamping,		and its implementation. In order to facilitate accurate timestamping,
	an implementation MAY use a hardware based timestamping engine, as		an implementation can use a hardware based timestamping engine, as
	shown in Figure 1. In such cases, the OWAMP/TWMAP packets are sent		shown in Figure 1. In such cases, the OWAMP/TWMAP packets are sent
	and received by a software layer, whereas the timestamping engine		and received by a software layer, whereas the timestamping engine
	modifies every outgoing test packet by incorporating its accurate		modifies every outgoing test packet by incorporating its accurate
	transmission time into the <Timestamp> field in the packet.		transmission time into the <Timestamp> field in the packet.
	OWAMP/TWAMP-enabled Node		OWAMP/TWAMP-enabled Node
	+-------------------+		+-------------------+
	| |		| |
	| +-----------+ |		| +-----------+ |
	Software | |OWAMP/TWAMP| |		Software | |OWAMP/TWAMP| |
	skipping to change at page 4, line 6		skipping to change at page 4, line 6
	/ \		/ \
	\__/\_ ___/		\__/\_ ___/
	\_/		\_/
	Figure 1 Accurate Timestamping in OWAMP/TWAMP		Figure 1 Accurate Timestamping in OWAMP/TWAMP
	OWAMP/TWAMP test packets are transported over UDP. When the UDP		OWAMP/TWAMP test packets are transported over UDP. When the UDP
	payload is changed by an intermediate entity such as the timestamping		payload is changed by an intermediate entity such as the timestamping
	engine, the UDP Checksum field must be updated to reflect the new		engine, the UDP Checksum field must be updated to reflect the new
	payload. When using UDP over IPv4 ([UDP]), an intermediate entity		payload. When using UDP over IPv4 ([UDP]), an intermediate entity
	that cannot update the value of the UDP checksum can assign a value		that cannot update the value of the UDP checksum has no choice except
	of zero to the checksum field, causing the receiver to ignore the		to assign a value of zero to the checksum field, causing the receiver
	checksum field. UDP over IPv6, as defined in [IPv6], does not allow a		to ignore the checksum field and potentially accept corrupted
	zero checksum, and requires the UDP checksum field to contain a		packets. UDP over IPv6, as defined in [IPv6], does not allow a zero
	correct checksum of the UDP payload.		checksum, except in specific cases [ZeroChecksum]. As discussed in
			[ZeroChecksum], the use of a zero checksum is generally not
			recommended, and should be avoided to the extent possible.
	Since an intermediate entity only modifies a specific field in the		Since an intermediate entity only modifies a specific field in the
	packet, i.e. the timestamp field, the UDP checksum update can be		packet, i.e. the timestamp field, the UDP checksum update can be
	performed incrementally, using the concepts presented in [Checksum].		performed incrementally, using the concepts presented in [Checksum].
	A similar problem is addressed in Annex E of [IEEE1588]. When the		A similar problem is addressed in Annex E of [IEEE1588]. When the
	Precision Time Protocol (PTP) is transported over IPv6, two octets		Precision Time Protocol (PTP) is transported over IPv6, two octets
	are appended to the end of the PTP payload for UDP checksum updates.		are appended to the end of the PTP payload for UDP checksum updates.
	The value of these two octets can be updated by an intermediate		The value of these two octets can be updated by an intermediate
	entity, causing the value of the UDP checksum field to remain		entity, causing the value of the UDP checksum field to remain
	skipping to change at page 5, line 38		skipping to change at page 5, line 40
	v +----------------------------------+		v +----------------------------------+
	Figure 2 Checksum Complement in OWAMP/TWAMP Test Packet		Figure 2 Checksum Complement in OWAMP/TWAMP Test Packet
	3.2. OWAMP / TWAMP Test Packets with Checksum Complement		3.2. OWAMP / TWAMP Test Packets with Checksum Complement
	The One-Way Active Measurement Protocol [OWAMP], and the Two-Way		The One-Way Active Measurement Protocol [OWAMP], and the Two-Way
	Active Measurement Protocol [TWAMP] both make use of timestamped test		Active Measurement Protocol [TWAMP] both make use of timestamped test
	packets. A Checksum Complement MAY be used in the following cases:		packets. A Checksum Complement MAY be used in the following cases:
	o In OWAMP test packets, sent by the sender to the receiver.		o In OWAMP test packets, sent by the sender to the receiver.
	o In TWAMP test packets, sent by the sender to the reflector.		o In TWAMP test packets, sent by the sender to the reflector.
	o In TWAMP test packets, sent by the reflector to the sender.		o In TWAMP test packets, sent by the reflector to the sender.
	OWAMP/TWAMP test packets are transported over UDP, either over IPv4		OWAMP/TWAMP test packets are transported over UDP, either over IPv4
	or over IPv6. This document applies to both OWAMP/TWAMP over IPv4 and		or over IPv6. This document applies to both OWAMP/TWAMP over IPv4 and
	over IPv6.		over IPv6.
	OWAMP/TWAMP test packets contain a Packet Padding field. This		OWAMP/TWAMP test packets contain a Packet Padding field. This
	document proposes to use the last 2 octets of the Packet Padding		document proposes to use the last 2 octets of the Packet Padding
	field as the Checksum Complement. In this case the Checksum		field as the Checksum Complement. In this case the Checksum
	Complement is always the last 2 octets of the UDP payload, and thus		Complement is always the last 2 octets of the UDP payload, and thus
	the field is located UDP Length - 2 octets after the beginning of the		the field is located UDP Length - 2 octets after the beginning of the
	skipping to change at page 6, line 31		skipping to change at page 6, line 31
	| |		| |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Error Estimate | |		| Error Estimate | |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
	| |		| |
	. Packet Padding .		. Packet Padding .
	. .		. .
	| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| | Checksum Complement |		| | Checksum Complement |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Figure 3 Checksum Complement in OWAMP Test Packets		Figure 3 Checksum Complement in OWAMP Test Packets
	Figure 4 illustrates the TWAMP test packet format including the UDP		Figure 4 illustrates the TWAMP test packet format including the UDP
	Checksum Complement.		Checksum Complement.
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Sequence Number |		| Sequence Number |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Timestamp |		| Timestamp |
	skipping to change at page 7, line 34		skipping to change at page 7, line 34
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Sender TTL | |		| Sender TTL | |
	+-+-+-+-+-+-+-+-+ +		+-+-+-+-+-+-+-+-+ +
	| |		| |
	. .		. .
	. Packet Padding .		. Packet Padding .
	. .		. .
	| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| | Checksum Complement |		| | Checksum Complement |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Figure 4 Checksum Complement in TWAMP Test Packets		Figure 4 Checksum Complement in TWAMP Test Packets
	The length of the Packet Padding field in test packets is announced		The length of the Packet Padding field in test packets is announced
	during the session initiation through the <Padding Length> field in		during the session initiation through the <Padding Length> field in
	the Request-Session message [OWAMP], or in the Request-TW-Session		the Request-Session message [OWAMP], or in the Request-TW-Session
	[TWAMP].		[TWAMP].
	When a Checksum Complement is included, the <Padding Length> MUST be		When a Checksum Complement is included, the <Padding Length> MUST be
	sufficiently long to include the Checksum Complement:		sufficiently long to include the Checksum Complement:
	o In OWAMP the padding length is at least 2 octets, allowing the		o In OWAMP the padding length is at least 2 octets, allowing the
	sender to incorporate the Checksum Complement in the last 2 octets		sender to incorporate the Checksum Complement in the last 2 octets
	of the padding.		of the padding.
	o In TWAMP the padding length is at least 29 octets. The additional		o In TWAMP the padding length is at least 29 octets. The additional
	padding is required since the header of reflector test packets is		padding is required since the header of reflector test packets is
	27 octets longer than the header of sender test packets. Thus, the		27 octets longer than the header of sender test packets. Thus, the
	padding in reflector test packets is 27 octets shorter than in		padding in reflector test packets is 27 octets shorter than in
	sender packet. Using 29 octets of padding in sender test packets		sender packet. Using 29 octets of padding in sender test packets
	allows both the sender and the reflector to use a 2-octet Checksum		allows both the sender and the reflector to use a 2-octet Checksum
	Complement.		Complement.
	Note: the 27-octet difference between the sender packet and the		Note: the 27-octet difference between the sender packet and the
	reflector packet is specifically in unauthenticated mode, whereas		reflector packet is specifically in unauthenticated mode, whereas
	in authenticated mode the difference between the sender and		in authenticated mode the difference between the sender and
	receiver packets is 56 octets. As specified in Section 3.4. , the		receiver packets is 56 octets. As specified in Section 3.4. , the
	Checksum Complement should only be used in unauthenticated mode.		Checksum Complement should only be used in unauthenticated mode.
	o Two optional TWAMP features are defined in [RFC6038]: octet		o Two optional TWAMP features are defined in [RFC6038]: octet
	reflection and symmetrical size. When at least one of these		reflection and symmetrical size. When at least one of these
	features is enabled, the Request-TW-Session includes the <Padding		features is enabled, the Request-TW-Session includes the <Padding
	Length> field, as well as a <Length of padding to reflect> field.		Length> field, as well as a <Length of padding to reflect> field.
	In this case both fields must be sufficiently long to allow at		In this case both fields must be sufficiently long to allow at
	least 2 octets of padding in both sender test packets and		least 2 octets of padding in both sender test packets and
	reflector test packets.		reflector test packets.
	Specifically, when octet reflection is enabled, the two length		Specifically, when octet reflection is enabled, the two length
	fields must be defined such that the padding expands at least 2		fields must be defined such that the padding expands at least 2
	octets beyond the end of the reflected octets.		octets beyond the end of the reflected octets.
	skipping to change at page 9, line 8		skipping to change at page 9, line 8
	A transmitter that includes a Checksum Complement in its outgoing		A transmitter that includes a Checksum Complement in its outgoing
	test packets MUST include a Packet Padding in these packets, the		test packets MUST include a Packet Padding in these packets, the
	length of which MUST be sufficient to include the Checksum		length of which MUST be sufficient to include the Checksum
	Complement. The length of the padding field is negotiated during		Complement. The length of the padding field is negotiated during
	session initiation, as described in Section 3.2.		session initiation, as described in Section 3.2.
	3.2.2. Intermediate Updates of OWAMP/TWAMP with Checksum Complement		3.2.2. Intermediate Updates of OWAMP/TWAMP with Checksum Complement
	An intermediate entity that receives and alters an OWAMP/TWAMP test		An intermediate entity that receives and alters an OWAMP/TWAMP test
	packet MAY alter the Checksum Complement field in order to maintain		packet can alter either the UDP Checksum field or the Checksum
	the correctness of the UDP checksum value.		Complement field in order to maintain the correctness of the UDP
			checksum value.
	3.2.3. Reception of OWAMP/TWAMP with Checksum Complement		3.2.3. Reception of OWAMP/TWAMP with Checksum Complement
	This document does not impose new requirements on the receiving end		This document does not impose new requirements on the receiving end
	of an OWAMP/TWAMP test packet.		of an OWAMP/TWAMP test packet.
	The UDP layer at the receiving end verifies the UDP Checksum of		The UDP layer at the receiving end verifies the UDP Checksum of
	received test packets, and the OWAMP/TWAMP layer SHOULD treat the		received test packets, and the OWAMP/TWAMP layer SHOULD treat the
	Checksum Complement as part of the Packet Padding.		Checksum Complement as part of the Packet Padding.
	skipping to change at page 10, line 10		skipping to change at page 10, line 13
	is encrypted.		is encrypted.
	A Checksum Complement SHOULD NOT be used in encrypted mode. The		A Checksum Complement SHOULD NOT be used in encrypted mode. The
	Checksum Complement is effective in unauthenticated and in		Checksum Complement is effective in unauthenticated and in
	authenticated mode, allowing the intermediate entity to perform		authenticated mode, allowing the intermediate entity to perform
	serial processing of the packet without storing-and-forwarding it.		serial processing of the packet without storing-and-forwarding it.
	On the other hand, in encrypted mode an intermediate entity that		On the other hand, in encrypted mode an intermediate entity that
	timestamps a test packet must also re-encrypt the packet accordingly.		timestamps a test packet must also re-encrypt the packet accordingly.
	Re-encryption typically requires the intermediate entity to store the		Re-encryption typically requires the intermediate entity to store the
	packet, re-encrypt it, and then forward it. Thus, the benefit of the		packet, re-encrypt it, and then forward it. Thus, from an
	Checksum Complement is effectively irrelevant in encrypted mode.		implementer's perspective, the Checksum Complement has very little
			value in encrypted mode, as it does not necessarily simplify the
			implementation.
	Note: while [OWAMP] and [TWAMP] include an inherent security		Note: while [OWAMP] and [TWAMP] include an inherent security
	mechanism, these protocols can be secured by other measures, e.g.,		mechanism, these protocols can be secured by other measures, e.g.,
	[IPPMIPsec]. For similar reasons as described above, a Checksum		[IPPMIPsec]. For similar reasons as described above, a Checksum
	Complement SHOULD NOT be used in this case.		Complement SHOULD NOT be used in this case.
	4. Security Considerations		4. Security Considerations
	This document describes how a Checksum Complement extension can be		This document describes how a Checksum Complement extension can be
	used for maintaining the correctness of the UDP checksum.		used for maintaining the correctness of the UDP checksum.
	skipping to change at page 10, line 39		skipping to change at page 10, line 44
	should be considered a malicious MITM attack.		should be considered a malicious MITM attack.
	It is important to emphasize that the scheme described in this		It is important to emphasize that the scheme described in this
	document does not increase the protocol's vulnerability to MITM		document does not increase the protocol's vulnerability to MITM
	attacks; a MITM who maliciously modifies a packet and its Checksum		attacks; a MITM who maliciously modifies a packet and its Checksum
	Complement is logically equivalent to a MITM attacker who modifies a		Complement is logically equivalent to a MITM attacker who modifies a
	packet and its UDP Checksum field.		packet and its UDP Checksum field.
	The concept described in this document is intended to be used only in		The concept described in this document is intended to be used only in
	unauthenticated or in authenticated mode. As described in Section		unauthenticated or in authenticated mode. As described in Section
	3.4. , the benefits of the Checksum Complement do not apply when		3.4.2. , in encrypted mode using the Checksum Complement does not
	encryption is enabled.		simplify the implementation compared to using the conventional
			Checksum, and therefore the Checksum Complement should not be used.
	5. IANA Considerations		5. IANA Considerations
	There are no IANA actions required by this document.		There are no IANA actions required by this document.
	RFC Editor: please delete this section before publication.		RFC Editor: please delete this section before publication.
	6. Acknowledgments		6. Acknowledgments
	The authors gratefully acknowledge Al Morton, Greg Mirsky, and Steve		The authors gratefully acknowledge Al Morton, Greg Mirsky, and Steve
	skipping to change at page 11, line 49		skipping to change at page 11, line 51
	7.2. Informative References		7.2. Informative References
	[IEEE1588] IEEE TC 9 Instrumentation and Measurement Society,		[IEEE1588] IEEE TC 9 Instrumentation and Measurement Society,
	"1588 IEEE Standard for a Precision Clock		"1588 IEEE Standard for a Precision Clock
	Synchronization Protocol for Networked Measurement and		Synchronization Protocol for Networked Measurement and
	Control Systems Version 2", IEEE Standard, 2008.		Control Systems Version 2", IEEE Standard, 2008.
	[IPPMIPsec] Pentikousis, K., Zhang, E., Cui, Y., "IKEv2-based		[IPPMIPsec] Pentikousis, K., Zhang, E., Cui, Y., "IKEv2-based
	Shared Secret Key for O/TWAMP", draft-ietf-ippm-ipsec		Shared Secret Key for O/TWAMP", draft-ietf-ippm-ipsec
	(work in progress), February 2015.		(work in progress), May 2015.
			[ZeroChecksum] Fairhurst, G., Westerlund, M., "Applicability
			Statement for the Use of IPv6 UDP Datagrams with Zero
			Checksums", RFC 6936, April 2013.
	Authors' Addresses		Authors' Addresses
	Tal Mizrahi		Tal Mizrahi
	Marvell		Marvell
	6 Hamada St.		6 Hamada St.
	Yokneam, 20692 Israel		Yokneam, 20692 Israel
	Email: talmi@marvell.com		Email: talmi@marvell.com
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