draft-ietf-mpls-tp-identifiers-05.txt		draft-ietf-mpls-tp-identifiers-06.txt
	MPLS Working Group M. Bocci		MPLS Working Group M. Bocci
	Internet-Draft Alcatel-Lucent		Internet-Draft Alcatel-Lucent
	Intended status: Standards Track G. Swallow		Intended status: Standards Track G. Swallow
	Expires: December 16, 2011 Cisco		Expires: December 26, 2011 Cisco
	E. Gray		E. Gray
	Ericsson		Ericsson
	June 14, 2011		June 24, 2011
	MPLS-TP Identifiers		MPLS-TP Identifiers
	draft-ietf-mpls-tp-identifiers-05		draft-ietf-mpls-tp-identifiers-06
	Abstract		Abstract
	This document specifies identifiers for MPLS-TP objects. Included		This document specifies an initial set of identifiers to be used in
	are identifiers conformant to existing ITU conventions and		the Transport Profile of Multiprotocol Label Switching (MPLS-TP).
	identifiers which are compatible with existing IP, MPLS, GMPLS, and		The MPLS-TP requirements (RFC 5654) require that the elements and
	Pseudowire definitions.		objects in an MPLS-TP environment are able to be configured and
			managed without a control plane. In such an environment many
			conventions for defining identifiers are possible. This document
			defines identifiers for MPLS-TP management and OAM functions suitable
			to IP/MPLS conventions.
	This document is a product of a joint Internet Engineering Task Force		This document is a product of a joint Internet Engineering Task Force
	(IETF) / International Telecommunication Union Telecommunication		(IETF) / International Telecommunication Union Telecommunication
	Standardization Sector (ITU-T) effort to include an MPLS Transport		Standardization Sector (ITU-T) effort to include an MPLS Transport
	Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge		Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge
	(PWE3) architectures to support the capabilities and functionalities		(PWE3) architectures to support the capabilities and functionalities
	of a packet transport network as defined by the ITU-T.		of a packet transport network as defined by the ITU-T.
	Status of this Memo		Status of this Memo
	skipping to change at page 1, line 43		skipping to change at page 1, line 47
	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-
	Drafts is at http://datatracker.ietf.org/drafts/current/.		Drafts is at http://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	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."
	This Internet-Draft will expire on December 16, 2011.		This Internet-Draft will expire on December 26, 2011.
	Copyright Notice		Copyright Notice
	Copyright (c) 2011 IETF Trust and the persons identified as the		Copyright (c) 2011 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
	skipping to change at page 2, line 17		skipping to change at page 2, line 19
	(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 . . . . . . . . . . . . . . . . . . . . . . . . . 4		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
	1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4		1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
	1.2. Requirements Language . . . . . . . . . . . . . . . . . . 5		1.2. Requirements Language . . . . . . . . . . . . . . . . . . 4
	1.3. Notational Conventions . . . . . . . . . . . . . . . . . . 5		1.3. Notational Conventions . . . . . . . . . . . . . . . . . . 4
	2. Named Entities . . . . . . . . . . . . . . . . . . . . . . . . 6		2. Named Entities . . . . . . . . . . . . . . . . . . . . . . . . 4
	3. Uniquely Identifying an Operator . . . . . . . . . . . . . . . 6		3. Uniquely Identifying an Operator - the Global_ID . . . . . . . 5
	3.1. The Global ID . . . . . . . . . . . . . . . . . . . . . . 7		4. Node and Interface Identifiers . . . . . . . . . . . . . . . . 6
	3.2. ITU Carrier Code . . . . . . . . . . . . . . . . . . . . . 7		5. MPLS-TP Tunnel and LSP Identifiers . . . . . . . . . . . . . . 7
	4. Node and Interface Identifiers . . . . . . . . . . . . . . . . 8		5.1. MPLS-TP Point to Point Tunnel Identifiers . . . . . . . . 8
	5. MPLS-TP Tunnel and LSP Identifiers . . . . . . . . . . . . . . 9		5.2. MPLS-TP LSP Identifiers . . . . . . . . . . . . . . . . . 8
	5.1. MPLS-TP Point to Point Tunnel Identifiers . . . . . . . . 9		5.2.1. MPLS-TP Co-Routed Bidirectional LSP Identifiers . . . 8
	5.2. MPLS-TP LSP Identifiers . . . . . . . . . . . . . . . . . 10		5.2.2. MPLS-TP Associated Bidirectional LSP Identifiers . . . 9
	5.2.1. MPLS-TP Co-Routed Bidirectional LSP Identifiers . . . 10		5.3. Mapping to RSVP Signaling . . . . . . . . . . . . . . . . 9
	5.2.2. MPLS-TP Associated Bidirectional LSP Identifiers . . . 11		6. Pseudowire Path Identifiers . . . . . . . . . . . . . . . . . 11
	5.3. Mapping to RSVP Signaling . . . . . . . . . . . . . . . . 12		7. Maintenance Identifiers . . . . . . . . . . . . . . . . . . . 12
	6. Pseudowire Path Identifiers . . . . . . . . . . . . . . . . . 13		7.1. Maintenance Entity Group Identifiers . . . . . . . . . . . 12
	7. Maintenance Identifiers . . . . . . . . . . . . . . . . . . . 14		7.1.1. MPLS-TP Section MEG_IDs . . . . . . . . . . . . . . . 12
	7.1. Maintenance Entity Group Identifiers . . . . . . . . . . . 14		7.1.2. MPLS-TP LSP MEG_IDs . . . . . . . . . . . . . . . . . 12
	7.1.1. ICC-based MEG Identifiers . . . . . . . . . . . . . . 14		7.1.3. Pseudowire MEG_IDs . . . . . . . . . . . . . . . . . . 13
	7.1.2. IP Compatible MEG_IDs . . . . . . . . . . . . . . . . 14		7.2. MEP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 13
	7.1.2.1. MPLS-TP Section MEG_IDs . . . . . . . . . . . . . 14		7.2.1. MPLS-TP LSP_MEP_ID . . . . . . . . . . . . . . . . . . 13
	7.1.2.2. MPLS-TP LSP MEG_IDs . . . . . . . . . . . . . . . 15		7.2.2. MEP_IDs for Pseudowires . . . . . . . . . . . . . . . 14
	7.1.2.3. Pseudowire MEG_IDs . . . . . . . . . . . . . . . . 15		7.3. Pseudowire Segment Endpoint IDs . . . . . . . . . . . . . 14
	7.2. MEP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 15		7.4. MIP Identifiers . . . . . . . . . . . . . . . . . . . . . 15
	7.2.1. ICC-based MEP Identifiers . . . . . . . . . . . . . . 15		8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
	7.2.2. IP based MEP_IDs . . . . . . . . . . . . . . . . . . . 15		9. Security Considerations . . . . . . . . . . . . . . . . . . . 15
	7.2.2.1. MPLS-TP LSP_MEP_ID . . . . . . . . . . . . . . . . 15		10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16
	7.2.2.2. MEP_IDs for Pseudowires . . . . . . . . . . . . . 16		10.1. Normative References . . . . . . . . . . . . . . . . . . . 16
	7.2.2.3. Pseudowire Segments Endpoint IDs . . . . . . . . . 16		10.2. Informative References . . . . . . . . . . . . . . . . . . 16
	7.3. MIP Identifiers . . . . . . . . . . . . . . . . . . . . . 17		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
	8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
	9. Security Considerations . . . . . . . . . . . . . . . . . . . 18
	10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18
	10.1. Normative References . . . . . . . . . . . . . . . . . . . 18
	10.2. Informative References . . . . . . . . . . . . . . . . . . 18
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
	1. Introduction		1. Introduction
	This document specifies identifiers to be used in the Transport		This document specifies an initial set of identifiers to be used in
	Profile of Multiprotocol Label Switching (MPLS-TP). The MPLS-TP		the Transport Profile of Multiprotocol Label Switching (MPLS-TP).
	requirements (RFC 5654) [7] require that the elements and objects in		The MPLS-TP requirements (RFC 5654) [7] require that the elements and
	an MPLS-TP environment are able to be configured and managed without		objects in an MPLS-TP environment are able to be configured and
	a control plane. In such an environment many conventions for		managed without a control plane. In such an environment many
	defining identifiers are possible. This document defines identifiers		conventions for defining identifiers are possible. This document
	for MPLS-TP management and OAM functions suitable to ITU conventions		defines identifiers for MPLS-TP management and OAM functions suitable
	and to IP/MPLS conventions. Applicability of the different		to IP/MPLS conventions. The identifiers have been chosen to be
	identifier schemas to different applications is outside the scope of		compatible with existing IP, MPLS, GMPLS, and Pseudowire definitions.
	this document.
	This document is a product of a joint Internet Engineering Task Force		This document is a product of a joint Internet Engineering Task Force
	(IETF) / International Telecommunication Union Telecommunication		(IETF) / International Telecommunication Union Telecommunication
	Standardization Sector (ITU-T) effort to include an MPLS Transport		Standardization Sector (ITU-T) effort to include an MPLS Transport
	Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge		Profile within the IETF MPLS and Pseudowire Emulation Edge-to-Edge
	(PWE3) architectures to support the capabilities and functionalities		(PWE3) architectures to support the capabilities and functionalities
	of a packet transport network as defined by the ITU-T.		of a packet transport network as defined by the ITU-T.
	1.1. Terminology		1.1. Terminology
	AII: Attachment Interface Identifier		AII: Attachment Interface Identifier
	ASN: Autonomous System Number		ASN: Autonomous System Number
	EGP: Exterior Gateway Protocol		EGP: Exterior Gateway Protocol
	FEC: Forwarding Equivalence Class		FEC: Forwarding Equivalence Class
	GMPLS: Generalized Multi-Protocol Label Switching		GMPLS: Generalized Multi-Protocol Label Switching
	ICC: ITU Carrier Code
	IGP: Interior Gateway Protocol		IGP: Interior Gateway Protocol
	LSP: Label Switched Path		LSP: Label Switched Path
	LSR: Label Switching Router		LSR: Label Switching Router
	ME: Maintenance Entity
	MEG: Maintenance Entity Group		MEG: Maintenance Entity Group
	MEP: Maintenance Entity Group End Point		MEP: Maintenance Entity Group End Point
	MIP: Maintenance Entity Group Intermediate Point		MIP: Maintenance Entity Group Intermediate Point
	MPLS: Multi-Protocol Label Switching		MPLS: Multi-Protocol Label Switching
	NNI: Network-to-Network Interface		NNI: Network-to-Network Interface
	OAM: Operations, Administration and Maintenance		OAM: Operations, Administration and Maintenance
	P2MP: Point to Multi-Point
	P2P: Point to Point		P2P: Point to Point
	PW: Pseudowire		PW: Pseudowire
	RSVP: Resource Reservation Protocol		RSVP: Resource Reservation Protocol
	RSVP-TE: RSVP Traffic Engineering		RSVP-TE: RSVP Traffic Engineering
	S-PE: Switching Provider Edge		S-PE: Switching Provider Edge
	skipping to change at page 6, line 5		skipping to change at page 4, line 45
	Specifically the designation A1 is used to indicate the lower sort		Specifically the designation A1 is used to indicate the lower sort
	order of a field or set of fields and Z9 is used to indicated the		order of a field or set of fields and Z9 is used to indicated the
	higher sort order of the same. The sort is either alphanumeric or		higher sort order of the same. The sort is either alphanumeric or
	numeric depending on the field's definition. Where the sort applies		numeric depending on the field's definition. Where the sort applies
	to a group of fields, those fields are grouped with {...}.		to a group of fields, those fields are grouped with {...}.
	Note, however, that the uniqueness of an identifier does not depend		Note, however, that the uniqueness of an identifier does not depend
	on the ordering, but rather, upon the uniqueness and scoping of the		on the ordering, but rather, upon the uniqueness and scoping of the
	fields that compose the identifier. Further the preferred ordering		fields that compose the identifier. Further the preferred ordering
	is not intended to constrain protocol designs by dictating a		is not intended to constrain protocol designs by dictating a
	particular field sequence or even what fields appear in which		particular field sequence (for example see Section 5.2.1) or even
	objects. For example see Section 5.3.		what fields appear in which objects (for example see Section 5.3).
	2. Named Entities		2. Named Entities
	In order to configure, operate and manage a transport network based		In order to configure, operate and manage a transport network based
	on the MPLS Transport Profile, a number of entities require		on the MPLS Transport Profile, a number of entities require
	identification. Identifiers for the following entities are defined		identification. Identifiers for the following entities are defined
	in this document:		in this document:
	* Operator		* Global_ID
	+ Global_ID		* Node
	+ ICC		* Interface
	* LSR		* Tunnel
	* LSP		* LSP
	* PW		* PW
	* Interface
	* MEG		* MEG
	* MEP		* MEP
	* MIP		* MIP
	* Tunnel
	Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209)		Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209)
	[2] where it is used to describe an entity that provides a logical		[2] where it is used to describe an entity that provides a logical
	association between a source and destination LSR. The tunnel in turn		association between a source and destination LSR. The tunnel in turn
	is instantiated by one or more LSPs, where the additional LSPs are		is instantiated by one or more LSPs, where the additional LSPs are
	used for protection or re-grooming of the tunnel.		used for protection or re-grooming of the tunnel.
	3. Uniquely Identifying an Operator		3. Uniquely Identifying an Operator - the Global_ID
	An operator is uniquely identified by an identifier which may take
	one of two formats. One format is compatible with IP operational
	practice, and is called a Global_ID. The other format is compatible
	with ITU practice and is called ICC. An operator MAY use either the
	Global_ID or ICC format.
	3.1. The Global ID
	RFC 5003 [3] defines a globally unique Attachment Interface		The Global_ID is defined to uniquely identify an operator. RFC 5003
	Identifier (AII). That AII is composed of three parts, a Global_ID		[3] defines a globally unique Attachment Interface Identifier (AII).
	which uniquely identifies an operator, a prefix, and finally, an		That AII is composed of three parts, a Global_ID which uniquely
	attachment circuit identifier. We have chosen to use that Global ID		identifies an operator, a prefix, and finally, an attachment circuit
	for MPLS-TP. Quoting from RFC 5003, section 3.2, "The global ID can		identifier. We have chosen to use that Global ID for MPLS-TP.
	contain the 2-octet or 4-octet value of the operator's Autonomous		Quoting from RFC 5003, section 3.2, "The global ID can contain the
	System Number (ASN). It is expected that the global ID will be		2-octet or 4-octet value of the operator's Autonomous System Number
	derived from the globally unique ASN of the autonomous system hosting		(ASN). It is expected that the global ID will be derived from the
	the PEs containing the actual AIIs. The presence of a global ID		globally unique ASN of the autonomous system hosting the PEs
	based on the operator's ASN ensures that the AII will be globally		containing the actual AIIs. The presence of a global ID based on the
	unique."		operator's ASN ensures that the AII will be globally unique."
	A Global_ID must be derived from a 4-octet AS number assigned to the		A Global_ID must be derived from a 4-octet AS number assigned to the
	operator. Note that 2-octet AS numbers have been incorporated in the		operator. Note that 2-octet AS numbers have been incorporated in the
	4-octet by placing the 2-octet AS number, in the low-order octets and		4-octet by placing the 2-octet AS number, in the low-order octets and
	setting the two high-order octets to zero.		setting the two high-order octets to zero.
	ASN 0 is reserved and cannot be assigned. A Global_ID of zero means		ASN 0 is reserved and cannot be assigned. A Global_ID of zero means
	that no Global_ID is specified. Note that a Global_ID of zero is		that no Global_ID is specified. Note that a Global_ID of zero is
	limited to entities contained within a single operator and MUST NOT		limited to entities contained within a single operator and MUST NOT
	be used across an NNI.		be used across an NNI.
	The Global_ID is used solely to provide a globally unique context for		The Global_ID is used solely to provide a globally unique context for
	other MPLS-TP identifiers. While the AS Number used in the Global_ID		other MPLS-TP identifiers. While the AS Number used in the Global_ID
	MUST be one which the operator is entitles to use, the use of the		MUST be one which the operator is entitled to use, the use of the
	Global_ID is not related to the use of the ASN in protocols such as		Global_ID is not related to the use of the ASN in protocols such as
	BGP.		BGP.
	3.2. ITU Carrier Code
	M.1400 defines the ITU Carrier Code (ICC) assigned to a network
	operator/service provider and maintained by the ITU-T
	Telecommunication Standardization Bureau (TSB): www.itu.int/ITU-T/
	inr/icc/index.html.
	ICCs can be assigned both to ITU-T and non-ITU-T members and the
	referenced local ICC website may contain ICCs of operators of both
	kinds.
	The ICC is a string of one to six characters, each character being
	either alphabetic (i.e. A-Z) or numeric (i.e. 0-9) characters.
	Alphabetic characters in the ICC SHOULD be represented with upper
	case letters.
	4. Node and Interface Identifiers		4. Node and Interface Identifiers
	An LSR requires identification of the node itself and of its		An LSR requires identification of the node itself and of its
	interfaces. An interface is the attachment point to a server		interfaces. An interface is the attachment point to a server
	(sub-)layer, e.g., MPLS-TP section or MPLS-TP tunnel.		(sub-)layer, e.g., MPLS-TP section or MPLS-TP tunnel.
	We call the identifier associated with a node a Node Identifier		We call the identifier associated with a node a Node Identifier
	(Node_ID). The Node_ID is a unique 32-bit value assigned by the		(Node_ID). The Node_ID is a unique 32-bit value assigned by the
	operator within the scope of a Global_ID or ICC. The structure of		operator within the scope of a Global_ID. The structure of the
	the Node_ID is operator specific and is outside the scope of this		Node_ID is operator specific and is outside the scope of this
	document. However, the value zero is reserved and MUST NOT be used.		document. However, the value zero is reserved and MUST NOT be used.
	Where IPv4 addresses are used, it may be convenient to use the Node's		Where IPv4 addresses are used, it may be convenient to use the Node's
	IPv4 loopback address as the Node_ID, however the Node_ID does not		IPv4 loopback address as the Node_ID, however the Node_ID does not
	need to have any association with the IPv4 address space used in the		need to have any association with the IPv4 address space used in the
	operator's IGP or EGP. Where IPv6 addresses are used exclusively, a		operator's IGP or EGP. Where IPv6 addresses are used exclusively, a
	32-bit value unique within the scope of a Global_ID or ICC is		32-bit value unique within the scope of a Global_ID is assigned.
	assigned.
	An LSR can support multiple layers (e.g. hierarchical LSPs) and the		An LSR can support multiple layers (e.g. hierarchical LSPs) and the
	Node_ID belongs to the multiple layer context i.e. it is applicable		Node_ID belongs to the multiple layer context i.e. it is applicable
	to all LSPs or PWs that originate on, have a intermediate point on,		to all LSPs or PWs that originate on, have a intermediate point on,
	or terminate on the node.		or terminate on the node.
	In situations where a Node_ID needs to be globally unique, this is		In situations where a Node_ID needs to be globally unique, this is
	accomplished by prefixing the identifier with the operator's		accomplished by prefixing the identifier with the operator's
	Global_ID or ICC.		Global_ID.
	Within the context of a particular node, we call the identifier		Within the context of a particular node, we call the identifier
	associated with an interface an Interface Number (IF_Num). The		associated with an interface an Interface Number (IF_Num). The
	IF_Num is a 32-bit unsigned integer assigned by the operator and MUST		IF_Num is a 32-bit unsigned integer assigned by the operator and MUST
	be unique within the scope of a Node_ID. The IF_Num value 0 has		be unique within the scope of a Node_ID. The IF_Num value 0 has
	special meaning (see Section 7.3, MIP Identifiers) and MUST NOT be		special meaning (see Section 7.4, MIP Identifiers) and MUST NOT be
	used to identify an MPLS-TP interface.		used to identify an MPLS-TP interface.
	An Interface Identifier (IF_ID) identifies an interface uniquely		An Interface Identifier (IF_ID) identifies an interface uniquely
	within the context of a Global_ID or ICC. It is formed by		within the context of a Global_ID. It is formed by concatenating the
	concatenating the Node_ID with the IF_Num. That is an IF_ID is a 64-		Node_ID with the IF_Num. That is, an IF_ID is a 64-bit identifier
	bit identifier formed as Node_ID::IF_Num.		formed as Node_ID::IF_Num.
	This convention was chosen to allow compatibility with GMPLS. GMPLS		This convention was chosen to allow compatibility with GMPLS. The
	signaling [4] requires interface identification. GMPLS allows three		GMPLS signaling functional description [4] requires interface
	formats for the Interface_ID. The third format consists of an IPv4		identification. GMPLS allows three formats for the Interface_ID.
	Address plus a 32-bit unsigned integer for the specific interface.		The third format consists of an IPv4 Address plus a 32-bit unsigned
	The format defined for MPLS-TP is consistent with this format, but		integer for the specific interface. The format defined for MPLS-TP
	uses the Node_ID instead of an IPv4 Address.		is consistent with this format, but uses the Node_ID instead of an
			IPv4 Address.
	If an IF_ID needs to be globally unique, this is accomplished by		If an IF_ID needs to be globally unique, this is accomplished by
	prefixing the identifier with the operator's Global_ID or ICC.		prefixing the identifier with the operator's Global_ID.
	The attachment point to an MPLS-TP Tunnel (see Section 5.1) also		The attachment point to an MPLS-TP Tunnel (see Section 5.1) also
	needs an interface identifier. Note that MPLS-TP supports		needs an interface identifier. Note that MPLS-TP supports
	hierarchical tunnels. The attachment point to a MPLS-TP Tunnel at		hierarchical tunnels. The attachment point to a MPLS-TP Tunnel at
	any (sub-)layer requires a node-unique IF_Num.		any (sub-)layer requires a node-unique IF_Num.
	5. MPLS-TP Tunnel and LSP Identifiers		5. MPLS-TP Tunnel and LSP Identifiers
	In MPLS the actual transport of packets is provided by label switched		In MPLS the actual transport of packets is provided by label switched
	paths (LSPs). A transport service may be composed of multiple LSPs.		paths (LSPs). A transport service may be composed of multiple LSPs.
	Further the LSPs providing a service may change over time due to		Further the LSPs providing a service may change over time due to
	protection and restoration events. In order to clearly identify the		protection and restoration events. In order to clearly identify the
	service we use the term "MPLS-TP Tunnel" or simply "tunnel" for a		service we use the term "MPLS-TP Tunnel" or simply "tunnel" for a
	service provided by (for example) a working LSP and protected by a		service provided by (for example) a working LSP and protected by a
	protection LSP. The Tunnel_ID identifies the transport service and		protection LSP. The Tunnel_ID identifies the transport service and
	provides a stable binding to the client in the face of changes in the		provides a stable binding to the client in the face of changes in the
	the data plane LSPs used to provide the service due to protection or		the data plane LSPs used to provide the service due to protection or
	restoration events. This section defines an MPLS-TP Tunnel_ID to		restoration events. This section defines an MPLS-TP Tunnel_ID to
	uniquely identify a tunnel and MPLS-TP LSP_IDs within the context of		uniquely identify a tunnel, and an MPLS-TP LSP_ID to uniquely
	that tunnel.		identify an LSP associated with a tunnel.
	For the case where multiple LSPs (for example) are used to support a		For the case where multiple LSPs (for example) are used to support a
	single service with a common set of end-points, using this identifier		single service with a common set of end-points, using the Tunnel_ID
	allows for a trivial mapping between the server and client layers,		allows for a trivial mapping between the server and client layers,
	providing a common service identifier which may be either defined by,		providing a common service identifier which may be either defined by,
	or used by, the client.		or used by, the client.
	Note that this usage is not intended to constrain protection schemes,		Note that this usage is not intended to constrain protection schemes,
	and may be used to identify any service (protected or unprotected)		and may be used to identify any service (protected or unprotected)
	that may appear to the client as a single service attachment point.		that may appear to the client as a single service attachment point.
	Keeping the Tunnel_ID consistent across working and protection LSPs		Keeping the Tunnel_ID consistent across working and protection LSPs
	is a useful construct currently employed within GMPLS. The Tunnel_ID		is a useful construct currently employed within GMPLS. However, the
	for a protection LSP MAY differ from that used by its corresponding		Tunnel_ID for a protection LSP MAY differ from that used by its
	working LSP.		corresponding working LSP.
	5.1. MPLS-TP Point to Point Tunnel Identifiers		5.1. MPLS-TP Point to Point Tunnel Identifiers
	At each endpoint a tunnel is uniquely identified by the endpoint's		At each endpoint a tunnel is uniquely identified by the endpoint's
	Node_ID and a locally assigned tunnel number. Specifically a		Node_ID and a locally assigned tunnel number. Specifically a
	Tunnel_Num is a 16-bit unsigned integer unique within the context of		Tunnel_Num is a 16-bit unsigned integer unique within the context of
	the Node_ID. The motivation for each endpoint having its own tunnel		the Node_ID. The motivation for each endpoint having its own tunnel
	number is to allow a compact form for the MEP-ID. See		number is to allow a compact form for the MEP-ID. See Section 7.2.1.
	Section 7.2.2.1.
	Having two tunnel numbers also serves to simplify other signaling		Having two tunnel numbers also serves to simplify other signaling
	(e.g., setup of associated bidirectional tunnels as described in		(e.g., setup of associated bidirectional tunnels as described in
	Section 5.3).		Section 5.3).
	The concatenation of the two endpoint identifiers serves as the full		The concatenation of the two endpoint identifiers serves as the full
	identifier. Using the A1 / Z9 convention the format of a Tunnel_ID		identifier. Using the A1/Z9 convention the format of a Tunnel_ID is:
	is:
	A1-{Node_ID::Tunnel_Num}::Z9-{Node_ID::Tunnel_Num}		A1-{Node_ID::Tunnel_Num}::Z9-{Node_ID::Tunnel_Num}
	Where the Tunnel_ID needs to be globally unique, this is accomplished		Where the Tunnel_ID needs to be globally unique, this is accomplished
	by using globally unique Node_IDs as defined above. Thus a globally		by using globally unique Node_IDs as defined above. Thus a globally
	unique Tunnel_ID becomes:		unique Tunnel_ID becomes:
	A1-{Global_ID::Node_ID::Tunnel_Num}::Z9-{Global_Id::Node_ID::		A1-{Global_ID::Node_ID::Tunnel_Num}::Z9-{Global_Id::Node_ID::
	Tunnel_Num}		Tunnel_Num}
	The corresponding ICC-based version of this identifier would be:
	A1-{ICC::Node_ID::Tunnel_Num}::Z9-{ICC::Node_ID::Tunnel_Num}
	When an MPLS-TP Tunnel is configured, it MUST be assigned a unique		When an MPLS-TP Tunnel is configured, it MUST be assigned a unique
	IF_ID at each endpoint. As usual, the IF_ID is composed of the local		IF_ID at each endpoint. As usual, the IF_ID is composed of the local
	Node_ID concatenated with a 32-bit IF_Num.		Node_ID concatenated with a 32-bit IF_Num.
	5.2. MPLS-TP LSP Identifiers		5.2. MPLS-TP LSP Identifiers
	5.2.1. MPLS-TP Co-Routed Bidirectional LSP Identifiers		5.2.1. MPLS-TP Co-Routed Bidirectional LSP Identifiers
	A co-routed bidirectional LSP can be uniquely identified by a single		A co-routed bidirectional LSP can be uniquely identified by a single
	LSP number within the scope of an MPLS-TP Tunnel_ID. Specifically an		LSP number within the scope of an MPLS-TP Tunnel_ID. Specifically an
	LSP_Num is a 16-bit unsigned integer unique within the Tunnel_ID.		LSP_Num is a 16-bit unsigned integer unique within the Tunnel_ID.
	Thus the format of an MPLS-TP co-routed bidirectional LSP_ID is:		Thus the format of an MPLS-TP co-routed bidirectional LSP_ID is:
	A1-{Node_ID::Tunnel_Num}::Z9-{Node_ID::Tunnel_Num}::LSP_Num		A1-{Node_ID::Tunnel_Num}::Z9-{Node_ID::Tunnel_Num}::LSP_Num
	Note that the uniqueness of identifiers does not depend on the A1 /		Note that the uniqueness of identifiers does not depend on the A1/Z9
	Z9 sort ordering. Thus the identifier,		sort ordering. Thus the identifier
	Z9-{Node_ID::Tunnel_Num}::A1-{Node_ID::Tunnel_Num}::LSP_Num		Z9-{Node_ID::Tunnel_Num}::A1-{Node_ID::Tunnel_Num}::LSP_Num
	is synonymous with the one above.		is synonymous with the one above.
	At the dataplane level, a co-routed bidirectional LSP is composed of		At the dataplane level, a co-routed bidirectional LSP is composed of
	two unidirectional LSPs traversing the same links in opposite		two unidirectional LSPs traversing the same links in opposite
	directions. Since a co-routed bidirectional LSP is provisioned or		directions. Since a co-routed bidirectional LSP is provisioned or
	signaled as a single entity, a single LSP_Num is used for both		signaled as a single entity, a single LSP_Num is used for both
	unidirectional LSPs. The unidirectional LSPs can be referenced by		unidirectional LSPs. The unidirectional LSPs can be referenced by
	the identifiers:		the identifiers:
	Z9-Node_ID::Z9-Tunnel_Num::LSP_Num::A1-Node_ID and		A1-Node_ID::A1-Tunnel_Num::LSP_Num::Z9-Node_ID and
	A1-Node_ID::A1-Tunnel_Num::LSP_Num::Z9-Node_ID respectively.
			Z9-Node_ID::Z9-Tunnel_Num::LSP_Num::A1-Node_ID respectively.
	Where the LSP_ID needs to be globally unique, this is accomplished by		Where the LSP_ID needs to be globally unique, this is accomplished by
	using globally unique Node_IDs as defined above. Thus a globally		using globally unique Node_IDs as defined above. Thus a globally
	unique LSP_ID becomes:		unique LSP_ID becomes:
	A1-{Global_ID::Node_ID::Tunnel_Num}::Z9-{Global_Id::		A1-{Global_ID::Node_ID::Tunnel_Num}::Z9-{Global_Id::
	Node_ID::Tunnel_Num}::LSP_Num		Node_ID::Tunnel_Num}::LSP_Num
	The corresponding ICC-based version of this identifier would be:
	A1-{ICC::Node_ID::Tunnel_Num}::Z9-{ICC::Node_ID::Tunnel_Num}::
	LSP_Num
	5.2.2. MPLS-TP Associated Bidirectional LSP Identifiers		5.2.2. MPLS-TP Associated Bidirectional LSP Identifiers
	For an associated bidirectional LSP each of the unidirectional LSPs		For an associated bidirectional LSP each of the unidirectional LSPs
	from A1 to Z9 and Z9 to A1 require LSP_Nums. Each LSP is uniquely		from A1 to Z9 and Z9 to A1 require LSP_Nums. Each unidirectional LSP
	identified by a single LSP number within the scope of the ingress's		is uniquely identified by a single LSP number within the scope of the
	Tunnel_Num. Specifically an LSP_Num is a 16-bit unsigned integer		ingress's Tunnel_Num. Specifically an LSP_Num is a 16-bit unsigned
	unique within the Tunnel_Num. Thus the format of an MPLS-TP		integer unique within the scope of the ingress's Tunnel_Num. Thus the
	associated bidirectional LSP_ID is:		format of an MPLS-TP associated bidirectional LSP_ID is:
	A1-{Node_ID::Tunnel_Num::LSP_Num}::		A1-{Node_ID::Tunnel_Num::LSP_Num}::
	Z9-{Node_ID::Tunnel_Num::LSP_Num}		Z9-{Node_ID::Tunnel_Num::LSP_Num}
	At the dataplane level, an associated bidirectional LSP is composed		At the dataplane level, an associated bidirectional LSP is composed
	of two unidirectional LSPs between two nodes in opposite directions.		of two unidirectional LSPs between two nodes in opposite directions.
	The unidirectional LSPs may be referenced by the identifiers:		The unidirectional LSPs may be referenced by the identifiers:
	A1-Node_ID::A1-Tunnel_Num::A1-LSP_Num::Z9-Node_ID and		A1-Node_ID::A1-Tunnel_Num::A1-LSP_Num::Z9-Node_ID and
	Z9-Node_ID::Z9-Tunnel_Num::Z9-LSP_Num::A1-Node_ID respectively.		Z9-Node_ID::Z9-Tunnel_Num::Z9-LSP_Num::A1-Node_ID respectively.
	Where the LSP_ID needs to be globally unique, this is accomplished by		Where the LSP_ID needs to be globally unique, this is accomplished by
	using globally unique Node_IDs as defined above. Thus a globally		using globally unique Node_IDs as defined above. Thus a globally
	unique LSP_ID becomes:		unique LSP_ID becomes:
	A1-{Global_ID::Node_ID::Tunnel_Num::LSP_Num}::		A1-{Global_ID::Node_ID::Tunnel_Num::LSP_Num}::
	Z9-{Global_Id::Node_ID::Tunnel_Num::LSP_Num}		Z9-{Global_Id::Node_ID::Tunnel_Num::LSP_Num}
	The corresponding ICC-based version of this identifier would be:
	A1-{ICC::Node_ID::Tunnel_Num::LSP_Num}::
	Z9-{ICC::Node_ID::Tunnel_Num::LSP_Num}
	5.3. Mapping to RSVP Signaling		5.3. Mapping to RSVP Signaling
	This section is informative and exists to help understand the		This section is informative and exists to help understand the
	structure of the LSP IDs.		structure of the LSP IDs.
	Both GMPLS and RSVP-TE use RSVP signaling. This section defines the		GMPLS [5] is based on RSVP-TE [2]. This section defines the mapping
	mapping from an MPLS-TP LSP_ID to RSVP. At this time, RSVP has yet		from an MPLS-TP LSP_ID to RSVP-TE. At this time, RSVP-TE has yet to
	to be extended to accommodate Global_IDs. Thus a mapping is only		be extended to accommodate Global_IDs. Thus a mapping is only made
	made for the network unique form of the LSP_ID.		for the network unique form of the LSP_ID.
	RSVP signaling [5] uses a 5-tuple to uniquely identify an LSP within		GMPLS and RSVP-TE signaling use a 5-tuple to uniquely identify an LSP
	a operator's network. This tuple is composed of a Tunnel Endpoint		within a operator's network. This tuple is composed of a Tunnel
	Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender Address and		Endpoint Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender
	(RSVP) LSP_ID.		Address and (RSVP) LSP_ID.
	For a co-routed bidirectional LSP signaled from A1 to Z9, the mapping		For a co-routed bidirectional LSP signaled from A1 to Z9, the mapping
	to the GMPLS 5-tuple is as follows:		to the GMPLS 5-tuple is as follows:
	* Tunnel Endpoint Address = Z9-Node_ID		* Tunnel Endpoint Address = Z9-Node_ID
	* Tunnel_ID = A1-Tunnel_Num		* Tunnel_ID = A1-Tunnel_Num
	* Extended Tunnel_ID = A1-Node_ID		* Extended Tunnel_ID = A1-Node_ID
	* Tunnel Sender Address = A1-Node_ID		* Tunnel Sender Address = A1-Node_ID
	* (RSVP) LSP_ID = LSP_Num		* (RSVP) LSP_ID = LSP_Num
	An associated bidirectional LSP between two nodes A1 and Z9 consists		An associated bidirectional LSP between two nodes A1 and Z9 consists
	of two unidirectional LSPs, one from A1 to Z9 and one from Z9 to A1.		of two unidirectional LSPs, one from A1 to Z9 and one from Z9 to A1.
	In situations where a mapping to the RSVP 5-tuples is required, the		In situations where a mapping to the RSVP-TE 5-tuples is required,
	following mappings are used. For the A1 to Z9 LSP the mapping would		the following mappings are used. For the A1 to Z9 LSP the mapping
	be:		would be:
	* Tunnel Endpoint Address = Z9-Node_ID		* Tunnel Endpoint Address = Z9-Node_ID
	* Tunnel_ID = A1-Tunnel_Num		* Tunnel_ID = A1-Tunnel_Num
	* Extended Tunnel_ID = A1-Node_ID		* Extended Tunnel_ID = A1-Node_ID
	* Tunnel Sender Address = A1-Node_ID		* Tunnel Sender Address = A1-Node_ID
	* (RSVP) LSP_ID = A1-LSP_Num		* (RSVP) LSP_ID = A1-LSP_Num
	skipping to change at page 13, line 24		skipping to change at page 11, line 19
	6. Pseudowire Path Identifiers		6. Pseudowire Path Identifiers
	Pseudowire signaling (RFC 4447 [6]) defines two FECs used to signal		Pseudowire signaling (RFC 4447 [6]) defines two FECs used to signal
	pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined		pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined
	in RFC 5003 [3] fits the identification requirements of MPLS-TP.		in RFC 5003 [3] fits the identification requirements of MPLS-TP.
	In an MPLS-TP environment, a PW is identified by a set of identifiers		In an MPLS-TP environment, a PW is identified by a set of identifiers
	which can be mapped directly to the elements required by FEC 129 and		which can be mapped directly to the elements required by FEC 129 and
	AII Type 2. To distinguish this identifier from other Pseudowire		AII Type 2. To distinguish this identifier from other Pseudowire
	Identifiers, we call this a Pseudowire Path Identifier (PW_Path_Id).		Identifiers, we call this a Pseudowire Path Identifier (PW_Path_ID).
	The AII Type 2 is composed of three fields. These are the Global_ID,		The AII Type 2 is composed of three fields. These are the Global_ID,
	the Prefix, and the AC_ID. The Global_ID used in this document is		the Prefix, and the AC_ID. The Global_ID used in this document is
	identical to the Global_ID defined in RFC 5003. The Node_ID is used		identical to the Global_ID defined in RFC 5003. The Node_ID is used
	as the Prefix. The AC_ID is as defined in RFC 5003.		as the Prefix. The AC_ID is as defined in RFC 5003.
	To complete the FEC 129, all that is required is a Attachment Group		To complete the FEC 129, all that is required is an Attachment Group
	Identifier (AGI). That field is exactly as specified in RFC 4447.		Identifier (AGI). That field is exactly as specified in RFC 4447. A
	FEC 129 has a notion of Source AII (SAII) and Target AII (TAII).		(bidirectional) pseudowire consists of a pair of unidirectional LSPs,
	These terms are used relative to the direction of the signaling. In		one in each direction. Thus for signaling, FEC 129 has a notion of
	a purely configured environment when referring to the entire PW, this		Source AII (SAII) and Target AII (TAII). These terms are used
	distinction is not critical. That is a FEC 129 of AGIa::AIIb::AIIc		relative to the direction of the LSP.
	is equivalent to AGIa::AIIc::AIIb. We note that in a signaled
	environment, the required convention in RFC 4447 is that at a		In a purely configured environment when referring to the entire PW,
	particular endpoint, the AII associated with that endpoint comes		this distinction is not critical. That is a FEC 129 of AGIa::AIIb::
	first. The complete PW_Path_Id is:		AIIc is equivalent to AGIa::AIIc::AIIb.
			We note that in a signaled environment, the required convention in
			RFC 4447 is that at a particular endpoint, the AII associated with
			that endpoint comes first. The complete PW_Path_ID is:
	AGI::A1-{Global_ID::Node_ID::AC_ID}::		AGI::A1-{Global_ID::Node_ID::AC_ID}::
	Z9-{Global_Id::Node_ID::AC_ID}.		Z9-{Global_ID::Node_ID::AC_ID}.
	The corresponding ICC-based version for this identifier would be:		In a signaled environment the LSP from A1 to Z9 would be initiated
			with a label request from A1 to Z9 with the fields of the FEC 129
			completed as follows:
	AGI::A1-{ICC::Node_ID::AC_ID}::Z9-{ICC::Node_ID::AC_ID}		AGI = AGI
			SAAI = A1-{Global_ID::Node_ID::AC_ID}
			TAII = Z9-{Global_ID::Node_ID::AC_ID}
			The LSP from Z9 to A1 would signaled with:
			AGI = AGI
			SAAI = Z9-{Global_ID::Node_ID::AC_ID}
			TAII = A1-{Global_ID::Node_ID::AC_ID}
	7. Maintenance Identifiers		7. Maintenance Identifiers
	In MPLS-TP a Maintenance Entity Group (MEG) represents an Entity that		In MPLS-TP a Maintenance Entity Group (MEG) represents an Entity that
	requires management and defines a relationship between a set of		requires management and defines a relationship between a set of
	maintenance points. A maintenance point is either a Maintenance		maintenance points. A maintenance point is either a Maintenance
	Entity Group End-point (MEP) or a Maintenance Entity Group		Entity Group End-point (MEP) or a Maintenance Entity Group
	Intermediate Point (MIP). Maintenance points are uniquely associated		Intermediate Point (MIP). Maintenance points are uniquely associated
	with a MEG. Within the context of a MEG, MEPs and MIPs must be		with a MEG. Within the context of a MEG, MEPs and MIPs must be
	uniquely identified. This section defines a means of uniquely		uniquely identified. This section defines a means of uniquely
	identifying Maintenance Entity Groups, Maintenance Entities and		identifying Maintenance Entity Groups, Maintenance Entities and
	uniquely defining MEPs and MIPs within the context of a Maintenance		uniquely defining MEPs and MIPs within the context of a Maintenance
	Entity Group.		Entity Group.
	7.1. Maintenance Entity Group Identifiers		7.1. Maintenance Entity Group Identifiers
	Maintenance Entity Group Identifiers (MEG_IDs) are required for		Maintenance Entity Group Identifiers (MEG_IDs) are required for
	MPLS-TP sections, LSPs and Pseudowires. Two classes of MEG_IDs are		MPLS-TP sections, LSPs and Pseudowires. The formats were chosen to
	defined, one that follows the IP compatible identifier defined above		follow the IP compatible identifiers defined above.
	as well as the ICC-format.
	7.1.1. ICC-based MEG Identifiers
	MEG_ID for MPLS-TP LSPs and Pseudowires MAY use the globally unique
	ICC-based format.
	In this case, the MEG_ID is a string of up to thirteen characters,
	each character being either alphabetic (i.e. A-Z) or numeric (i.e.
	0-9) characters. It consists of two subfields: the ICC (as defined
	in section 3) followed by a unique MEG code (UMC). The UMC MUST be
	unique within the organization identified by the ICC.
	The ICC MEG_ID may be applied equally to a single MPLS-TP LSP or
	Pseudowires. Note that when encoded in a protocol such as in a TLV,
	a different type needs to be defined for LSP and PWs as the OAM
	capabilities may be different.
	7.1.2. IP Compatible MEG_IDs
	7.1.2.1. MPLS-TP Section MEG_IDs		7.1.1. MPLS-TP Section MEG_IDs
	IP compatible MEG_IDs for MPLS-TP sections are formed by		IP compatible MEG_IDs for MPLS-TP sections are formed by
	concatenating the two IF_IDs of the corresponding section. For		concatenating the two IF_IDs of the corresponding section using the
	example:		A1/Z9 ordering. For example:
	A1-IF_ID::Z9-IF_ID		A1-IF_ID::Z9-IF_ID
	Where the LSP_ID needs to be globally unique, this is accomplished by		Where the Section_MEG_ID needs to be globally unique, this is
	using globally unique Node_IDs as defined above. Thus a globally		accomplished by using globally unique Node_IDs as defined above.
	unique Section MEG_ID becomes:		Thus a globally unique Section_MEG_ID becomes:
	A1-{Global_ID::IF_ID}::Z9-{Global_Id::IF_ID}		A1-{Global_ID::IF_ID}::Z9-{Global_ID::IF_ID}
	7.1.2.2. MPLS-TP LSP MEG_IDs		7.1.2. MPLS-TP LSP MEG_IDs
	Since a MEG pertains to a single MPLS-TP LSP, IP compatible MEG_IDs		A MEG pertains to a unique MPLS-TP LSP. IP compatible MEG_IDs for
	for MPLS-TP LSPs are simply the corresponding LSP_IDs. We note that		MPLS-TP LSPs are simply the corresponding LSP_IDs, however, the the
	while the two identifiers are syntactically identical, they have		A1/Z9 ordering MUST be used. For bidirectional co-routed LSPs the
	different semantics. This semantic difference needs to be made		format of the LSP_ID is found in Section 5.2.1. For associated
	clear. For instance if both a MPLS-TP LSP_ID and MPLS-TP LSP MEG_IDs		bidirectional LSPs the format is in Section 5.2.2.
	are to be encoded in TLVs, different types need to be assigned for
	these two identifiers.
	7.1.2.3. Pseudowire MEG_IDs		We note that while the two identifiers are syntactically identical,
			they have different semantics. This semantic difference needs to be
			made clear. For instance if both a MPLS-TP LSP_ID and MPLS-TP LSP
			MEG_IDs are to be encoded in TLVs, different types need to be
			assigned for these two identifiers.
			7.1.3. Pseudowire MEG_IDs
	For Pseudowires a MEG pertains to a single PW. The IP compatible		For Pseudowires a MEG pertains to a single PW. The IP compatible
	MEG_ID for a PW is simply the corresponding PW_Path_ID. We note that		MEG_ID for a PW is simply the corresponding PW_Path_ID, however, the
	while the two identifiers are syntactically identical, they have		the A1/Z9 ordering MUST be used. The PW_Path_ID is described in
	different semantics. This semantic difference needs to be made		Section 6. We note that while the two identifiers are syntactically
	clear. For instance if both a PW_Path_ID and a PW_MEG_ID are to be		identical, they have different semantics. This semantic difference
	encoded in TLVs, different types need to be assigned for these two		needs to be made clear. For instance if both a PW_Path_ID and a
	identifiers.		PW_MEG_ID are to be encoded in TLVs, different types need to be
			assigned for these two identifiers.
	7.2. MEP_IDs		7.2. MEP_IDs
	7.2.1. ICC-based MEP Identifiers		7.2.1. MPLS-TP LSP_MEP_ID
	ICC-based MEP_IDs for MPLS-TP LSPs and Pseudowires are formed by
	appending a unique number to the MEG_ID defined in Section 7.1.1
	above. Within the context of a particular MEG, we call the
	identifier associated with a MEP the MEP Index (MEP_Index). The
	MEP_Index is administratively assigned. It is encoded as a 16-bit
	unsigned integer and MUST be unique within the MEG. An ICC-based
	MEP_ID is:
	MEG_ID::MEP_Index
	An ICC-based MEP ID is globally unique by construction given the ICC-
	based MEG_ID global uniqueness.
	7.2.2. IP based MEP_IDs
	7.2.2.1. MPLS-TP LSP_MEP_ID
	In order to automatically generate MEP_IDs for MPLS-TP LSPs, we use		In order to automatically generate MEP_IDs for MPLS-TP LSPs, we use
	the elements of identification that are unique to an endpoint. This		the elements of identification that are unique to an endpoint. This
	ensures that MEP_IDs are unique for all LSPs within a operator. When		ensures that MEP_IDs are unique for all LSPs within a operator. When
	Tunnels or LSPs cross operator boundaries, these are made unique by		Tunnels or LSPs cross operator boundaries, these are made unique by
	pre-pending them with the operator's Global_ID.		pre-pending them with the operator's Global_ID.
	The MPLS-TP LSP_MEP_ID is		The MPLS-TP LSP_MEP_ID is
	Node_ID::Tunnel_Num::LSP_Num		Node_ID::Tunnel_Num::LSP_Num
	skipping to change at page 16, line 21		skipping to change at page 14, line 5
	where the Node_ID is the node in which the MEP is located and		where the Node_ID is the node in which the MEP is located and
	Tunnel_Num is the tunnel number unique to that node. In the case of		Tunnel_Num is the tunnel number unique to that node. In the case of
	co-routed bidirectional LSPs, the single LSP_Num is used at both		co-routed bidirectional LSPs, the single LSP_Num is used at both
	ends. In the case of associated bidirectional LSPs, the LSP_Num is		ends. In the case of associated bidirectional LSPs, the LSP_Num is
	the one unique to where the MEP resides.		the one unique to where the MEP resides.
	In situations where global uniqueness is required this becomes:		In situations where global uniqueness is required this becomes:
	Global_ID::Node_ID::Tunnel_Num::LSP_Num		Global_ID::Node_ID::Tunnel_Num::LSP_Num
	7.2.2.2. MEP_IDs for Pseudowires		7.2.2. MEP_IDs for Pseudowires
	Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP_IDs. In		Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP_IDs. In
	order to automatically generate MEP_IDs for PWs, we simply use the		order to automatically generate MEP_IDs for PWs, we simply use the
	AGI plus the AII associated with that end of the PW. Thus a MEP_ID		AGI plus the AII associated with that end of the PW. Thus a MEP_ID
	used in end-to-end for an Pseudowire T-PE takes the form		used in end-to-end for a Pseudowire T-PE takes the form
	AGI:Global_ID::Node_ID::AC_ID,		AGI::Global_ID::Node_ID::AC_ID
	where the Node_ID is the node in which the MEP is located and the		where the Node_ID is the node in which the MEP is located and the
	AC_ID is the AC_ID of the Pseudowire at that node.		AC_ID is the AC_ID of the Pseudowire at that node.
	7.2.2.3. Pseudowire Segments Endpoint IDs		7.3. Pseudowire Segment Endpoint IDs
	In some OAM communications, messages are originated by the node at		In some OAM communications, messages are originated by the node at
	one end of a PW segment and relayed to the other end of that same		one end of a PW segment and relayed to the other end of that same
	segment by setting the TTL of the PW label to one (1). For a multi-		segment by setting the TTL of the PW label to one (1). For a multi-
	segment pseudowire, TTL could be set to any value that would cause		segment pseudowire, TTL could be set to any value that would cause
	OAM messages to reach the target segment end-point (up to and		OAM messages to reach the target segment end-point (up to and
	including 255). In such communications an identifier for the		including 255). In such communications an identifier for the
	pseudowire segment endpoint is needed. We call this a Pseudowire		pseudowire segment endpoint is needed. We call this a Pseudowire
	Segments Endpoint ID or PW_SE_ID.		Segments Endpoint ID or PW_SE_ID.
	skipping to change at page 17, line 38		skipping to change at page 15, line 25
	AGI1::GID1::PE1::AII1		AGI1::GID1::PE1::AII1
	The PW_SE_ID at point B would be -		The PW_SE_ID at point B would be -
	AGI1::GID1::PE4::AII4::GID1::PE2		AGI1::GID1::PE4::AII4::GID1::PE2
	The PW_SE_ID at point C would be -		The PW_SE_ID at point C would be -
	AGI1::GID1::PE1::AII1::GID1::PE2		AGI1::GID1::PE1::AII1::GID1::PE2
	7.3. MIP Identifiers		7.4. MIP Identifiers
	At a cross-connect point, in order to automatically generate MIP_IDs		At a cross-connect point, in order to automatically generate MIP_IDs
	for MPLS-TP, we simply use the IF_IDs of the two interfaces which are		for MPLS-TP, we simply use the IF_IDs of the two interfaces which are
	cross-connected via the label bindings of the MPLS-TP LSP or PW.		cross-connected via the label bindings of the MPLS-TP LSP or PW.
	This allows, two MIPs to be independently identified in one node		This allows, two MIPs to be independently identified in one node
	where a per-interface MIP model is used. If only a per node MIP		where a per-interface MIP model is used. If only a per node MIP
	model is used then one MIP is configured. In this case the MIP_ID is		model is used then one MIP is configured. In this case the MIP_ID is
	formed using the Node_ID and an IF_Num of 0.		formed using the Node_ID and an IF_Num of 0.
	8. IANA Considerations		8. IANA Considerations
End of changes. 64 change blocks.
	250 lines changed or deleted		179 lines changed or added
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