< draft-ietf-mpls-lsp-ping-reply-mode-simple-04-nobo.txt		draft-ietf-mpls-lsp-ping-reply-mode-simple-04-mach.txt >
	skipping to change at page 2, line 29		skipping to change at page 2, line 29
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Problem Statements . . . . . . . . . . . . . . . . . . . . . 3		2. Problem Statements . . . . . . . . . . . . . . . . . . . . . 3
	3. Solution . . . . . . . . . . . . . . . . . . . . . . . . . . 5		3. Solution . . . . . . . . . . . . . . . . . . . . . . . . . . 5
	3.1. Reply via Specified Path Update . . . . . . . . . . . . . 5		3.1. Reply via Specified Path Update . . . . . . . . . . . . . 5
	3.2. Reply Mode Order TLV . . . . . . . . . . . . . . . . . . 6		3.2. Reply Mode Order TLV . . . . . . . . . . . . . . . . . . 6
	4. Relations to Other LSP Ping/Trace Features . . . . . . . . . 7		4. Relations to Other LSP Ping/Trace Features . . . . . . . . . 7
	4.1. Backwards Compatibility with Reply via Specified Path (5)		4.1. Backwards Compatibility with Reply via Specified Path (5)
	Reply Mode . . . . . . . . . . . . . . . . . . . . . . . 7		Reply Mode . . . . . . . . . . . . . . . . . . . . . . . 8
	4.2. Reply Path TLV . . . . . . . . . . . . . . . . . . . . . 8		4.2. Reply Path TLV . . . . . . . . . . . . . . . . . . . . . 8
	4.2.1. Example 1: Reply Mode Order TLV Usage with Reply Path		4.2.1. Example 1: Reply Mode Order TLV Usage with Reply Path
	TLV . . . . . . . . . . . . . . . . . . . . . . . . . 8		TLV . . . . . . . . . . . . . . . . . . . . . . . . . 8
	4.2.2. Example 2: Reply Mode Order TLV Usage with Reply Path		4.2.2. Example 2: Reply Mode Order TLV Usage with Reply Path
	TLV . . . . . . . . . . . . . . . . . . . . . . . . . 9		TLV . . . . . . . . . . . . . . . . . . . . . . . . . 9
	4.3. Proxy LSP Ping . . . . . . . . . . . . . . . . . . . . . 9		4.3. Proxy LSP Ping . . . . . . . . . . . . . . . . . . . . . 9
	4.3.1. Proxy LSR Sending an MPLS Echo Request . . . . . . . 9		4.3.1. Proxy LSR Sending an MPLS Echo Request . . . . . . . 9
	4.3.2. Proxy LSR Sending an MPLS Proxy Ping Reply . . . . . 10		4.3.2. Proxy LSR Sending an MPLS Proxy Ping Reply . . . . . 10
	5. Security Considerations . . . . . . . . . . . . . . . . . . . 10		5. Security Considerations . . . . . . . . . . . . . . . . . . . 10
	6. Manageability Considerations . . . . . . . . . . . . . . . . 10		6. Manageability Considerations . . . . . . . . . . . . . . . . 10
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
	7.1. New Reply Mode Order TLV . . . . . . . . . . . . . . . . 11		7.1. New Reply Mode Order TLV . . . . . . . . . . . . . . . . 11
	8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11		8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
	9. Contributing Authors . . . . . . . . . . . . . . . . . . . . 11		9. Contributing Authors . . . . . . . . . . . . . . . . . . . . 11
	10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11		10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
	10.1. Normative References . . . . . . . . . . . . . . . . . . 11		10.1. Normative References . . . . . . . . . . . . . . . . . . 11
	10.2. Informative References . . . . . . . . . . . . . . . . . 12		10.2. Informative References . . . . . . . . . . . . . . . . . 12
	Appendix A. Reply Mode Order TLV Beneficial Scenarios . . . . . 12		Appendix A. Reply Mode Order TLV Beneficial Scenarios . . . . . 12
	A.1. Incorrect Forwarding Scenario . . . . . . . . . . . . . . 12		A.1. Incorrect Forwarding Scenario . . . . . . . . . . . . . . 12
	A.2. Non-Co-Routed Bidirectional LSP Scenario . . . . . . . . 13		A.2. Non-Co-Routed Bidirectional LSP Scenario . . . . . . . . 13
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
	1. Introduction		1. Introduction
	The MPLS LSP Ping, described in [RFC4379], allows an initiator LSR to		The Multiprotocol Label Switching (MPLS) Label Switched Path (LSP)
	encode instructions (Reply Mode) on how a responder LSR should send		Ping, described in [RFC4379], allows an initiator LSR to encode
	the response back to the initiator LSR. [RFC7110] also allows the		instructions (Reply Mode) on how a responder LSR should send the
			response back to the initiator LSR. [RFC7110] also allows the
	initiator LSR to encode a TLV (Reply Path TLV) which can instruct the		initiator LSR to encode a TLV (Reply Path TLV) which can instruct the
	responder LSR to use specific LSP to send the response back to the		responder LSR to use a specific LSP to send the response back to the
	initiator LSR. Both approaches are powerful as they provide the		initiator LSR. Both approaches are powerful as they provide the
	ability for the initiator LSR to control the return path.		ability for the initiator LSR to control the return path.
	However, it is becoming increasingly difficult for an initiator LSR		However, it is becoming increasingly difficult for an initiator LSR
	to select a valid return path to encode in the MPLS LSP echo request		to select a valid return path to encode in the MPLS LSP echo request
	packets. If the initiator LSR does not select a valid return path,		packets. If the initiator LSR does not select a valid return path,
	the MPLS LSP echo reply will not get back to the initiator LSR. This		the MPLS LSP echo reply will not get back to the initiator LSR. This
	results in a false failure of MPLS LSP Ping and Traceroute operation.		results in a false failure of MPLS LSP Ping and Traceroute operation.
	In an effort to minimize such false failures, different		In an effort to minimize such false failures, different
	implementations have chosen different default return path encoding		implementations have chosen different default return path encoding
	skipping to change at page 4, line 9		skipping to change at page 4, line 13
	several factors which are contributing to this complication.		several factors which are contributing to this complication.
	o Some LSPs have a control-channel, and some do not. Some LSPs have		o Some LSPs have a control-channel, and some do not. Some LSPs have
	a reverse LSP, and some do not. Some LSPs have IP reachability in		a reverse LSP, and some do not. Some LSPs have IP reachability in
	the reverse direction, and some do not.		the reverse direction, and some do not.
	o LSRs on some LSPs can have different available return path(s).		o LSRs on some LSPs can have different available return path(s).
	Available return path(s) can depend on whether the responder LSR		Available return path(s) can depend on whether the responder LSR
	is a transit LSR or an egress LSR. In case of a bi-directional		is a transit LSR or an egress LSR. In case of a bi-directional
	LSP, available return path(s) on transit LSRs can also depend on		LSP, available return path(s) on transit LSRs can also depend on
	whether LSP is completely co-routed, partially co-routed or		whether the LSP is completely co-routed, partially co-routed or
	associated (i.e., LSPs in the two directions are not co-routed).		associated (i.e., the LSPs in the two directions are not co-
			routed).
	o MPLS echo request packets may incorrectly terminate on an		o MPLS echo request packets may incorrectly terminate on an
	unintended target, which can have different available return		unintended target, which can have different available return
	path(s) than the intended target.		path(s) than the intended target.
	o The MPLS LSP Ping operation is expected to terminate on egress		o The MPLS LSP Ping operation is expected to terminate on an egress
	LSR. However, the MPLS LSP Ping operation with specific TTL		LSR. However, the MPLS LSP Ping operation with specific TTL
	values and MPLS LSP Traceroute operation can terminate on both		values and MPLS LSP Traceroute operation can terminate on both
	transit LSR(s) and the egress LSR.		transit LSR(s) and the egress LSR.
	Except for the case where the responder LSR does not have an IP route		Except for the case where the responder LSR does not have an IP route
	back to the initiator LSR, it is possible to use the "Reply via an		back to the initiator LSR, it is possible to use the "Reply via an
	IPv4/IPv6 UDP packet (2)" Reply Mode value in all cases. However,		IPv4/IPv6 UDP packet (2)" Reply Mode value in all cases. However,
	some operators are preferring control-channel and reverse LSP as		some operators are preferring control-channel and reverse LSP as
	default return path if they are available, which is not always the		default return path if they are available, which is not always the
	case.		case.
	skipping to change at page 6, line 19		skipping to change at page 6, line 26
	the Target FEC Stack TLV.		the Target FEC Stack TLV.
	3.2. Reply Mode Order TLV		3.2. Reply Mode Order TLV
	This document also introduces a new optional TLV to describe list of		This document also introduces a new optional TLV to describe list of
	Reply Mode values. The new TLV will contain one or more Reply Mode		Reply Mode values. The new TLV will contain one or more Reply Mode
	value(s) in preferred order. The first Reply Mode value is the most		value(s) in preferred order. The first Reply Mode value is the most
	preferred and the last Reply Mode value is the least preferred.		preferred and the last Reply Mode value is the least preferred.
	Following rules apply when using Reply Mode Order TLV.		Following rules apply when using Reply Mode Order TLV.
	1. The Reply Mode Order TLV MUST NOT be included in MPLS echo reply.		1. The Reply Mode Order TLV MUST NOT be included in any MPLS echo
	If the initiator LSR receives an MPLS echo reply with the Reply		reply. If the initiator LSR receives an MPLS echo reply with the
	Mode Order TLV, the initiator LSR MUST ignore the whole Reply		Reply Mode Order TLV, the initiator LSR MUST ignore the whole
	Mode Order TLV and MUST only use the value from the Reply Mode		Reply Mode Order TLV and MUST only use the value from the Reply
	field of the received MPLS echo reply. It may be beneficial for		Mode field of the received MPLS echo reply. It may be beneficial
	implementations to provide counters and/or loggings, with		for implementations to provide counters and/or loggings, with
	appropriate log dampening, to record this error case.		appropriate log dampening, to record this error case.
	2. The Reply Mode Order TLV MAY be included in MPLS echo request.		2. The Reply Mode Order TLV MAY be included in MPLS echo request.
	3. The Reply Mode field of an MPLS echo request MUST be set to a		3. The Reply Mode field of an MPLS echo request MUST be set to a
	valid value even when supplying the Reply Mode Order TLV. The		valid value even when supplying the Reply Mode Order TLV. The
	initiator LSR SHOULD set the Reply Mode field of MPLS echo		initiator LSR SHOULD set the Reply Mode field of an MPLS echo
	request to a value that corresponds to a return path which most		request to a value that corresponds to a return path which most
	likely to be available, in case the responder LSR does not		likely to be available, in case the responder LSR does not
	understand the Reply Mode Order TLV.		understand the Reply Mode Order TLV.
	4. If a responder LSR understands the Reply Mode Order TLV but the		4. If a responder LSR understands the Reply Mode Order TLV but the
	TLV is not valid (due to conditions described in the items 6, 7,		TLV is not valid (due to conditions described in the items 6, 7,
	8 and 9 immediately below), then the responder LSR MUST ignore		8 and 9 immediately below), then the responder LSR MUST ignore
	the whole Reply Mode Order TLV and MUST only use the value from		the whole Reply Mode Order TLV and MUST only use the value from
	the Reply Mode field of the received MPLS echo request. It may		the Reply Mode field of the received MPLS echo request. It may
	be beneficial for implementations to provide counters and/or		be beneficial for implementations to provide counters and/or
	loggings, with appropriate log dampening, to record this error		loggings, with appropriate log dampening, to record this error
	case.		case.
	5. If a responder LSR understands the Reply Mode Order TLV and the		5. If a responder LSR understands the Reply Mode Order TLV and the
	TLV is valid, then the responder LSR MUST consider the Reply Mode		TLV is valid, then the responder LSR MUST consider the Reply Mode
	values described in the TLV and MUST NOT use the value described		values described in the TLV and MUST NOT use the value described
	in the Reply Mode field of received MPLS echo request. In other		in the Reply Mode field of the received MPLS echo request. In
	words, a valid Reply Mode Order TLV overrides the value specified		other words, a valid Reply Mode Order TLV overrides the value
	in the Reply Mode field of received MPLS echo request.		specified in the Reply Mode field of the received MPLS echo
			request.
	6. Reply Mode Order TLV MUST contain at least one Reply Mode value.		6. Reply Mode Order TLV MUST contain at least one Reply Mode value.
	7. A Reply Mode value, except for Reply Mode value 5 (Reply via		7. A Reply Mode value, except for Reply Mode value 5 (Reply via
	Specified Path), MUST NOT be repeated (i.e., MUST NOT appear		Specified Path), MUST NOT be repeated (i.e., MUST NOT appear
	multiple times) in the Reply Mode Order TLV.		multiple times) in the Reply Mode Order TLV.
	8. The Reply Mode value 5 (Reply via Specified Path) MAY be included		8. The Reply Mode value 5 (Reply via Specified Path) MAY be included
	more than once in the Reply Mode Order TLV. However, in such		more than once in the Reply Mode Order TLV. However, in such
	case a Reply Path TLV MUST be included for all instances of the		case a Reply Path TLV MUST be included for all instances of the
	Reply Mode value 5 included in the Reply Mode Order TLV. In		Reply Mode value 5 included in the Reply Mode Order TLV. In
	other words, 3 instances of the Reply Mode value 5 in the Reply		other words, 3 instances of the Reply Mode value 5 in the Reply
	Mode Order TLV will require 3 instances of the Reply Path TLVs.		Mode Order TLV will require 3 instances of the Reply Path TLVs.
	9. The Reply Mode value 1 (Do not reply) MUST NOT be used in the		9. The Reply Mode value 1 (Do not reply) MUST NOT be used in the
	Reply Mode Order TLV.		Reply Mode Order TLV.
	The responder LSR SHOULD select the first available return path in		The responder LSR SHOULD select the first available return path in
	this TLV. The Reply Mode value corresponding to the selected return		this TLV. The Reply Mode value corresponding to the selected return
	path MUST be set in Reply Mode field of MPLS echo reply to		path MUST be set in Reply Mode field of the MPLS echo reply to
	communicate back to the initiator LSR which return path was chosen.		communicate back to the initiator LSR which return path was chosen.
	The format of the TLV is as follows:		The format of the TLV is as follows:
	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
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Reply Mode Order TLV Type | Length |		| Reply Mode Order TLV Type | Length |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	~ Reply mode 1 | Reply mode 2 | Reply mode 3 | Reply mode 4 ~		~ Reply mode 1 | Reply mode 2 | Reply mode 3 | Reply mode 4 ~
	skipping to change at page 8, line 12		skipping to change at page 8, line 23
	considered invalid is now valid. If the initiator LSR, which sent an		considered invalid is now valid. If the initiator LSR, which sent an
	MPLS echo request message with the "Reply via Specified path (5)"		MPLS echo request message with the "Reply via Specified path (5)"
	Reply Mode but without including the "Reply Path TLV", receives back		Reply Mode but without including the "Reply Path TLV", receives back
	an MPLS echo reply message with the return code being "Malformed echo		an MPLS echo reply message with the return code being "Malformed echo
	request received", then the initiator LSR SHOULD assume that the		request received", then the initiator LSR SHOULD assume that the
	responder LSR does not support the mechanism defined in this		responder LSR does not support the mechanism defined in this
	document.		document.
	4.2. Reply Path TLV		4.2. Reply Path TLV
	[RFC7110] has defined that the "Reply Path TLV" can include Sub-TLVs		A "Reply Path TLV" [RFC7110] is defined to identify a single return
	describing multiple FECs, from which the responder LSR can choose the		path. When the initiator LSR wants to use the Reply Mode Order TLV
	FEC to send the MPLS echo reply message. [RFC7110] has also defined		to describe multiple return paths, then the initiator SHOULD include
	that Sub-TLVs, within the "Reply Path TLV", describing FECs for		multiple "Reply via Specified Path (5)" Reply mode values and
	return paths SHOULD be ignored when the B bit is set in the Flags		multiple corresponding "Reply Path TLV" objects (one "Reply Path TLV"
	field. Therefore, when the initiator LSR wants to use the Reply Mode		corresponding to each "Reply via Specified Path (5)", and one "Reply
	Order TLV to describe the reverse LSP and other FECs for return		Path TLV" identify a return path).
	paths, then the initiator SHOULD include two "Reply via Specified
	Path (5)" Reply Mode values and two "Reply Path TLV" objects (one
	"Reply Path TLV" corresponding to each "Reply via Specified Path
	(5)").
	o The reverse LSP is described by the "Reply via Specified Path (5)"
	Reply Mode value and the corresponding "Reply Path TLV" with the B
	bit set in the Flags field. In this "Reply Path TLV", no Sub-TLVs
	are present.
	o Other return FECs are described by the "Reply via Specified Path
	(5)" Reply Mode value and the corresponding "Reply Path TLV"
	describing the FECs for return paths. In this "Reply Path TLV",
	the B bit is cleared in the Flags field.
	4.2.1. Example 1: Reply Mode Order TLV Usage with Reply Path TLV		4.2.1. Example 1: Reply Mode Order TLV Usage with Reply Path TLV
	If the initiator LSR was interested in encoding following return		If the initiator LSR was interested in encoding following return
	paths:		paths:
	1. Reply via application level control channel		1. Reply via application level control channel
	2. FEC X		2. FEC X
	3. FEC Y		3. FEC Y
	4. Reply via an IPv4/IPv6 UDP packet		4. Reply via an IPv4/IPv6 UDP packet
	Then the MPLS echo request message is to carry:		Then the MPLS echo request message is to carry:
	o The Reply Mode Order TLV carrying Reply Modes {4, 5, 2}		o The Reply Mode Order TLV carrying Reply Modes {4, 5, 5, 2}
	o The Reply Path TLV carrying {FEC X, FEC Y}		o One Reply Path TLV carrying FEC X
			o One Reply Path TLV carrying FEC Y
	Described encoding of the Reply Mode Order TLV and the Reply Path TLV		Described encoding of the Reply Mode Order TLV and the Reply Path TLV
	in the MPLS echo request message will result in the responder LSR to		in the MPLS echo request message will result in the responder LSR to
	prefer "Reply via application level control channel (4)", followed by		prefer "Reply via application level control channel (4)", followed by
	FEC X, FEC Y and then "Reply via an IPv4/IPv6 UDP packet (2)".		FEC X, FEC Y and then "Reply via an IPv4/IPv6 UDP packet (2)".
	4.2.2. Example 2: Reply Mode Order TLV Usage with Reply Path TLV		4.2.2. Example 2: Reply Mode Order TLV Usage with Reply Path TLV
	If the initiator LSR was interested in encoding following return		If the initiator LSR was interested in encoding following return
	paths:		paths:
	1. Reverse LSP		1. Reverse LSP
	2. Reply via an IPv4/IPv6 UDP packet		2. Reply via an IPv4/IPv6 UDP packet
	3. FEC X		3. FEC X
	4. FEC Y		4. FEC Y
	Then the MPLS echo request message is to carry:		Then the MPLS echo request message is to carry:
	o The Reply Mode Order TLV carrying Reply Modes {5, 2, 5}		o The Reply Mode Order TLV carrying Reply Modes {5, 2, 5, 5}
	o One Reply Path TLV with the B bit set.		o One Reply Path TLV with the B bit set.
	o One Reply Path TLV carrying {FEC X, FEC Y}		o One Reply Path TLV carrying FEC X
			o One Reply Path TLV carrying FEC Y
	Described encoding of the Reply Mode Order TLV and the Reply Path TLV		Described encoding of the Reply Mode Order TLV and the Reply Path TLV
	in the MPLS echo request message will result in the responder LSR to		in the MPLS echo request message will result in the responder LSR to
	prefer the reverse LSP, followed by "Reply via an IPv4/IPv6 UDP		prefer the reverse LSP, followed by "Reply via an IPv4/IPv6 UDP
	packet (2)", FEC X and then FEC Y.		packet (2)", FEC X and then FEC Y.
	4.3. Proxy LSP Ping		4.3. Proxy LSP Ping
	The mechanism defined in this document will work with Proxy LSP Ping		The mechanism defined in this document will work with Proxy LSP Ping
	defined by [RFC7555]. The MPLS proxy ping request message can carry		defined by [RFC7555]. The MPLS proxy ping request message can carry
	a Reply Mode value in the header and one or more Reply Mode values in		a Reply Mode value in the header and one or more Reply Mode values in
	the Reply Mode Order TLV. It is RECOMMENDED that the Reply Mode 2		the Reply Mode Order TLV. It is RECOMMENDED that the Reply Mode 2
	(Reply via an IPv4/IPv6 UDP packet) be used in the Reply Mode field		(Reply via an IPv4/IPv6 UDP packet) be used in the Reply Mode field
	of the MPLS proxy ping request message.		of the MPLS proxy ping request message.
	4.3.1. Proxy LSR Sending an MPLS Echo Request		4.3.1. Proxy LSR Sending an MPLS Echo Request
	If the proxy LSR is sending an MPLS echo request, then the proxy LSR		If the proxy LSR is sending an MPLS echo request, then the proxy LSR
	MUST copy following elements from the MPLS proxy ping request message		MUST copy the following elements from the MPLS proxy ping request
	to the MPLS echo request message.		message to the MPLS echo request message.
	o The Reply Mode field.		o The Reply Mode field.
	o The Reply Mode Order TLV.		o The Reply Mode Order TLV.
	o The Reply Path TLV(s). If there are more than one Reply Path		o The Reply Path TLV(s). If there are more than one Reply Path
	TLVs, then then order of them MUST be preserved when copying.		TLVs, then order of them MUST be preserved when copying.
	4.3.2. Proxy LSR Sending an MPLS Proxy Ping Reply		4.3.2. Proxy LSR Sending an MPLS Proxy Ping Reply
	If the proxy LSR is sending an MPLS proxy ping reply, then it is		If the proxy LSR is sending an MPLS proxy ping reply, then it is
	RECOMMENDED that the Reply Mode Order TLV be ignored and the Reply		RECOMMENDED that the Reply Mode Order TLV is ignored and the Reply
	Mode field in the MPLS proxy ping request message be used.		Mode field in the MPLS proxy ping request message is used.
	5. Security Considerations		5. Security Considerations
	Beyond those specified in [RFC4379] and [RFC7110], there are no		Beyond those specified in [RFC4379] and [RFC7110], there are no
	further security measures required.		further security measures required.
	6. Manageability Considerations		6. Manageability Considerations
	Section 2 described the problems which increases the complexity with		Section 2 described the problems which increases the complexity with
	respect to operations and implementations. In order to to simplify		respect to operations and implementations. In order to simplify
	operations and to allow for the LSP Ping/Traceroute to function		operations and to allow for the LSP Ping/Traceroute to function
	efficiently whilst preserving the code simplicity, it is RECOMMENDED		efficiently whilst preserving the code simplicity, it is RECOMMENDED
	that implementations allow devices to have configuration options to		that implementations allow devices to have configuration options to
	set operator preferred Reply Modes. For example:		set operator preferred Reply Modes. For example:
	o For those operators who are more interested in MPLS echo reply		o For those operators who are more interested in MPLS echo reply
	packets reaching back to the initiator LSR:		packets reaching back to the initiator LSR:
	1. Reply via an IPv4/IPv6 UDP packet (2)		1. Reply via an IPv4/IPv6 UDP packet (2)
End of changes. 19 change blocks.
	51 lines changed or deleted		44 lines changed or added
This html diff was produced by rfcdiff 1.42. The latest version is available from http://tools.ietf.org/tools/rfcdiff/

X-Generator: pyht 0.35