< draft-ietf-bier-ospf-bier-extensions-10.txt		draft-ietf-bier-ospf-bier-extensions-11.txt >
	OSPF P. Psenak, Ed.		OSPF P. Psenak, Ed.
	Internet-Draft N. Kumar		Internet-Draft N. Kumar
	Intended status: Standards Track IJ. Wijnands		Intended status: Standards Track IJ. Wijnands
	Expires: June 7, 2018 Cisco		Expires: August 16, 2018 Cisco
	A. Dolganow		A. Dolganow
	Nokia		Nokia
	T. Przygienda		T. Przygienda
	J. Zhang		J. Zhang
	Juniper Networks, Inc.		Juniper Networks, Inc.
	S. Aldrin		S. Aldrin
	Google, Inc.		Google, Inc.
	December 4, 2017		February 12, 2018
	OSPF Extensions for BIER		OSPF Extensions for BIER
	draft-ietf-bier-ospf-bier-extensions-10.txt		draft-ietf-bier-ospf-bier-extensions-11.txt
	Abstract		Abstract
	Bit Index Explicit Replication (BIER) is an architecture that		Bit Index Explicit Replication (BIER) is an architecture that
	provides multicast forwarding through a "BIER domain" without		provides multicast forwarding through a "BIER domain" without
	requiring intermediate routers to maintain multicast related per-flow		requiring intermediate routers to maintain multicast related per-flow
	state. Neither does BIER require an explicit tree-building protocol		state. Neither does BIER require an explicit tree-building protocol
	for its operation. A multicast data packet enters a BIER domain at a		for its operation. A multicast data packet enters a BIER domain at a
	"Bit-Forwarding Ingress Router" (BFIR), and leaves the BIER domain at		"Bit-Forwarding Ingress Router" (BFIR), and leaves the BIER domain at
	one or more "Bit-Forwarding Egress Routers" (BFERs). The BFIR router		one or more "Bit-Forwarding Egress Routers" (BFERs). The BFIR router
	adds a BIER header to the packet. Such header contains a bit-string		adds a BIER header to the packet. Such header contains a bit-string
	in which each bit represents exactly one BFER to forward the packet		in which each bit represents exactly one BFER to forward the packet
	to. The set of BFERs to which the multicast packet needs to be		to. The set of BFERs to which the multicast packet needs to be
	forwarded is expressed by the according set of bits set in BIER		forwarded is expressed by the according set of bits set in BIER
	packet header.		packet header.
	This document describes the OSPF protocol extension required for BIER		This document describes the OSPF [RFC2328] protocol extension
	with MPLS encapsulation.		required for BIER with MPLS encapsulation.
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	provisions of BCP 78 and BCP 79.		provisions of BCP 78 and BCP 79.
	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 https://datatracker.ietf.org/drafts/current/.		Drafts is at https://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 June 7, 2018.		This Internet-Draft will expire on August 16, 2018.
	Copyright Notice		Copyright Notice
	Copyright (c) 2017 IETF Trust and the persons identified as the		Copyright (c) 2018 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
	(https://trustee.ietf.org/license-info) in effect on the date of		(https://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
	skipping to change at page 3, line 10 ¶		skipping to change at page 3, line 10 ¶
	contains a bit-string in which each bit represents exactly one BFER		contains a bit-string in which each bit represents exactly one BFER
	to forward the packet to. The set of BFERs to which the multicast		to forward the packet to. The set of BFERs to which the multicast
	packet needs to be forwarded is expressed by setting the bits that		packet needs to be forwarded is expressed by setting the bits that
	correspond to those routers in the BIER header.		correspond to those routers in the BIER header.
	BIER architecture requires routers participating in BIER to exchange		BIER architecture requires routers participating in BIER to exchange
	BIER related information within a given domain. BIER architecture		BIER related information within a given domain. BIER architecture
	permits link-state routing protocols to perform distribution of such		permits link-state routing protocols to perform distribution of such
	information. This document describes extensions to OSPF necessary to		information. This document describes extensions to OSPF necessary to
	advertise BIER specific information in the case where BIER uses MPLS		advertise BIER specific information in the case where BIER uses MPLS
	encapsulation as described in [I-D.ietf-bier-mpls-encapsulation].		encapsulation as described in [RFC8296].
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in [RFC2119].		document are to be interpreted as described in [RFC2119].
	2. Flooding of the BIER Information in OSPF		2. Flooding of the BIER Information in OSPF
	All BIER specific information that a Bit-Forwarding Router (BFR)		All BIER specific information that a Bit-Forwarding Router (BFR)
	needs to advertise to other BFRs is associated with a BFR-Prefix. A		needs to advertise to other BFRs is associated with a BFR-Prefix. A
	BFR prefix is a unique (within a given BIER domain) routable IP		BFR prefix is a unique (within a given BIER domain) routable IP
	address that is assigned to each BFR as described in more detail in		address that is assigned to each BFR as described in more detail in
	section 2 of [I-D.ietf-bier-architecture].		section 2 of [RFC8279].
	Given that BIER information must be associated with a BFR prefix, the		Given that BIER information must be associated with a BFR prefix, the
	OSPF Extended Prefix Opaque LSA [RFC7684] has been chosen for		OSPF Extended Prefix Opaque LSA [RFC7684] has been chosen for
	advertisement.		advertisement.
	2.1. BIER Sub-TLV		2.1. BIER Sub-TLV
	A Sub-TLV of the Extended Prefix TLV (defined in [RFC7684]) is		A Sub-TLV of the Extended Prefix TLV (defined in [RFC7684]) is
	defined for distributing BIER information. The Sub-TLV is called the		defined for distributing BIER information. The Sub-TLV is called the
	BIER Sub-TLV. Multiple BIER Sub-TLVs may be included in the Extended		BIER Sub-TLV. Multiple BIER Sub-TLVs may be included in the Extended
	skipping to change at page 4, line 7 ¶		skipping to change at page 4, line 7 ¶
	| BAR | Reserved |		| BAR | Reserved |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Sub-TLVs (variable) |		| Sub-TLVs (variable) |
	+- -+		+- -+
	| |		| |
	Type: 9		Type: 9
	Length: Variable, dependent on sub-TLVs.		Length: Variable, dependent on sub-TLVs.
	Sub-domain-ID: Unique value identifying the BIER sub-domain within		Sub-domain-ID: Unique value identifying the BIER sub-domain within
	the BIER domain, as described in section 1 of		the BIER domain, as described in section 1 of [RFC8279].
	[I-D.ietf-bier-architecture].
	MT-ID: Multi-Topology ID (as defined in [RFC4915]) that identifies		MT-ID: Multi-Topology ID (as defined in [RFC4915]) that identifies
	the topology that is associated with the BIER sub-domain.		the topology that is associated with the BIER sub-domain.
	BFR-id: A 2 octet field encoding the BFR-id, as documented in		BFR-id: A 2 octet field encoding the BFR-id, as documented in
	section 2 of [I-D.ietf-bier-architecture]. If the BFR is not		section 2 of [RFC8279]. If the BFR is not locally configured with
	locally configured with a valid BFR-id, the value of this field is		a valid BFR-id, the value of this field is set to invalid BFR-id
	set to invalid BFR-id per [I-D.ietf-bier-architecture].		per [RFC8279].
	BAR: Single octet BIER Algorithm. 0 is the only supported value		BAR: Single octet BIER Algorithm. 0 is the only supported value
	defined in this document and represents Shortest Path First (SPF)		defined in this document and represents Shortest Path First (SPF)
	algorithm based on IGP link metric. This is the standard shortest		algorithm based on IGP link metric. This is the standard shortest
	path algorithm as computed by the OSPF protocol. Other values may		path algorithm as computed by the OSPF protocol. Other values may
	be defined in the future.		be defined in the future.
	Each BFR sub-domain MUST be associated with one and only one OSPF		Each BFR sub-domain MUST be associated with one and only one OSPF
	topology that is identified by the MT-ID. If the association between		topology that is identified by the MT-ID. If the association between
	BIER sub-domain and OSPF topology advertised in the BIER sub-TLV by		BIER sub-domain and OSPF topology advertised in the BIER sub-TLV by
	skipping to change at page 5, line 12 ¶		skipping to change at page 5, line 10 ¶
	MPLS specific information used for BIER. It MAY appear multiple		MPLS specific information used for BIER. It MAY appear multiple
	times in the BIER Sub-TLV.		times in the BIER Sub-TLV.
	The BIER MPLS Encapsulation Sub-TLV has the following format:		The BIER MPLS Encapsulation Sub-TLV has the following format:
	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
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| Type | Length |		| Type | Length |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|Lbl Range Size | Label Range Base |		| Max SI | Label |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	|BS Len | Reserved |		|BS Len | Reserved |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Type: 10		Type: 10
	Length: 4 octets		Length: 4 octets
	Label Range Size: A 1 octet field encoding the label range size of		Max SI : A 1 octet field encoding the Maximum Set Identifier
	the label range. It MUST be greater then 0, otherwise the		(section 1 of [RFC8296]), used in the encapsulation for this BIER
	advertising router MUST be treated as if it did not advertise a		sub-domain for this bitstring length.
	BIER sub-TLV.
	Label Range Base: A 3 octet field, where the 20 rightmost bits		Label: A 3 octet field, where the 20 rightmost bits represent the
	represent the first label in the label range. The 4 leftmost bits		first label in the label range. The 4 leftmost bits MUST be
	MUST be ignored.		ignored.
	Bit String Length: A 4 bits field encoding the supported BitString		Bit String Length: A 4 bits field encoding the supported BitString
	length associated with this BFR-prefix. The values allowed in		length associated with this BFR-prefix. The values allowed in
	this field are specified in section 2 of		this field are specified in section 2 of [RFC8296].
	[I-D.ietf-bier-mpls-encapsulation].
	The "label range" is the set of labels beginning with the label		The "label range" is the set of labels beginning with the Label
	range base and ending with ((label range base)+(label range size)-		and ending with (Label + (Max SI)). A unique label range is
	1). A unique label range is allocated for each BitStream length		allocated for each BitStream length and Sub-domain-ID. These
	and Sub-domain-ID. These labels are used for BIER forwarding as		labels are used for BIER forwarding as described in [RFC8279] and
	described in [I-D.ietf-bier-architecture] and		[RFC8296].
	[I-D.ietf-bier-mpls-encapsulation].
	The size of the label range is determined by the number of Set		The size of the label range is determined by the number of Set
	Identifiers (SI) (section 1 of [I-D.ietf-bier-architecture]) that		Identifiers (SI) (section 1 of [RFC8279]) that are used in the
	are used in the network. Each SI maps to a single label in the		network. Each SI maps to a single label in the label range. The
	label range. The first label is for SI=0, the second label is for		first label is for SI=0, the second label is for SI=1, etc.
	SI=1, etc.
	If same BS length is repeated in multiple BIER MPLS Encapsulation		If same BS length is repeated in multiple BIER MPLS Encapsulation
	Sub-TLV inside the same BIER Sub-TLV, the BIER sub-TLV MUST be		Sub-TLV inside the same BIER Sub-TLV, the BIER sub-TLV MUST be
	ignored.		ignored.
	Label ranges within all BIER MPLS Encapsulation Sub-TLV inside the		Label ranges within all BIER MPLS Encapsulation Sub-TLV inside the
	same BIER Sub-TLV MUST NOT overlap. If the overlap is detected, the		same BIER Sub-TLV MUST NOT overlap. If the overlap is detected, the
	advertising router MUST be treated as if it did not advertise a BIER		advertising router MUST be treated as if it did not advertise a BIER
	sub-TLV.		sub-TLV.
	skipping to change at page 6, line 49 ¶		skipping to change at page 6, line 41 ¶
	- Examine its best path to the prefix in the source area and		- Examine its best path to the prefix in the source area and
	find the advertising router associated with the best path to		find the advertising router associated with the best path to
	that prefix.		that prefix.
	- Determine if such advertising router advertised a BIER Sub-		- Determine if such advertising router advertised a BIER Sub-
	TLV for the prefix. If yes, the ABR will copy the information		TLV for the prefix. If yes, the ABR will copy the information
	from such BIER Sub-TLV when advertising BIER Sub-TLV to each		from such BIER Sub-TLV when advertising BIER Sub-TLV to each
	attached area.		attached area.
	In the Figure 1, R1 advertises a prefix 192.0.0.1/32 in Area 1.		In the Figure 1, R1 advertises a prefix 192.0.2.1/32 in Area 1.
	It also advertises Extended Prefix Opaque LSA for prefix		It also advertises Extended Prefix Opaque LSA for prefix
	192.0.0.1/32 and includes BIER Sub-TLV in it. Area Border Router		192.0.2.1/32 and includes BIER Sub-TLV in it. Area Border Router
	(ABR) R2 calculates the reachability for prefix 192.0.0.1/32		(ABR) R2 calculates the reachability for prefix 192.0.2.1/32
	inside Area 1 and propagates it to Area 0. When doing so, it		inside Area 1 and propagates it to Area 0. When doing so, it
	copies the entire BIER Sub-TLV (including all its Sub-TLVs) it		copies the entire BIER Sub-TLV (including all its Sub-TLVs) it
	received from R1 in Area 1 and includes it in the Extended Prefix		received from R1 in Area 1 and includes it in the Extended Prefix
	Opaque LSA it generates for 192.0.0.1/32 in Area 0. ABR R3		Opaque LSA it generates for 192.0.2.1/32 in Area 0. ABR R3
	calculates the reachability for prefix 192.0.0.1/32 inside Area 0		calculates the reachability for prefix 192.0.2.1/32 inside Area 0
	and propagates it to Area 2. When doing so, it copies the entire		and propagates it to Area 2. When doing so, it copies the entire
	BIER Sub-TLV (including all its Sub-TLVs) it received from R2 in		BIER Sub-TLV (including all its Sub-TLVs) it received from R2 in
	Area 0 and includes it in the Extended Prefix Opaque LSA it		Area 0 and includes it in the Extended Prefix Opaque LSA it
	generates for 192.0.0.1/32 in Area 2.		generates for 192.0.2.1/32 in Area 2.
	3. Security Considerations		3. Security Considerations
	Implementations must assure that malformed TLV and Sub-TLV		Implementations must assure that malformed TLV and Sub-TLV
	permutations do not result in errors which cause hard OSPF failures.		permutations do not result in errors which cause hard OSPF failures.
	4. IANA Considerations		4. IANA Considerations
	The document requests three new allocations from the OSPF Extended		The document requests three new allocations from the OSPF Extended
	Prefix sub-TLV registry as defined in [RFC7684].		Prefix sub-TLV registry as defined in [RFC7684].
	skipping to change at page 7, line 37 ¶		skipping to change at page 7, line 29 ¶
	BIER MPLS Encapsulation Sub-TLV: 10		BIER MPLS Encapsulation Sub-TLV: 10
	5. Acknowledgments		5. Acknowledgments
	The authors would like to thank Rajiv Asati, Christian Martin, Greg		The authors would like to thank Rajiv Asati, Christian Martin, Greg
	Shepherd and Eric Rosen for their contribution.		Shepherd and Eric Rosen for their contribution.
	6. Normative References		6. Normative References
	[I-D.ietf-bier-architecture]
	Wijnands, I., Rosen, E., Dolganow, A., Przygienda, T., and
	S. Aldrin, "Multicast using Bit Index Explicit
	Replication", draft-ietf-bier-architecture-06 (work in
	progress), April 2017.
	[I-D.ietf-bier-mpls-encapsulation]
	Wijnands, I., Rosen, E., Dolganow, A., Tantsura, J.,
	Aldrin, S., and I. Meilik, "Encapsulation for Bit Index
	Explicit Replication in MPLS and non-MPLS Networks",
	draft-ietf-bier-mpls-encapsulation-07 (work in progress),
	June 2017.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119,		Requirement Levels", BCP 14, RFC 2119,
	DOI 10.17487/RFC2119, March 1997,		DOI 10.17487/RFC2119, March 1997,
	<https://www.rfc-editor.org/info/rfc2119>.		<https://www.rfc-editor.org/info/rfc2119>.
			[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
			DOI 10.17487/RFC2328, April 1998,
			<https://www.rfc-editor.org/info/rfc2328>.
	[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.		[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.
	Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",		Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",
	RFC 4915, DOI 10.17487/RFC4915, June 2007,		RFC 4915, DOI 10.17487/RFC4915, June 2007,
	<https://www.rfc-editor.org/info/rfc4915>.		<https://www.rfc-editor.org/info/rfc4915>.
	[RFC7120] Cotton, M., "Early IANA Allocation of Standards Track Code
	Points", BCP 100, RFC 7120, DOI 10.17487/RFC7120, January
	2014, <https://www.rfc-editor.org/info/rfc7120>.
	[RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,		[RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,
	Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute		Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute
	Advertisement", RFC 7684, DOI 10.17487/RFC7684, November		Advertisement", RFC 7684, DOI 10.17487/RFC7684, November
	2015, <https://www.rfc-editor.org/info/rfc7684>.		2015, <https://www.rfc-editor.org/info/rfc7684>.
	[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for		[RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
	Writing an IANA Considerations Section in RFCs", BCP 26,		Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
	RFC 8126, DOI 10.17487/RFC8126, June 2017,		Explicit Replication (BIER)", RFC 8279,
	<https://www.rfc-editor.org/info/rfc8126>.		DOI 10.17487/RFC8279, November 2017,
			<https://www.rfc-editor.org/info/rfc8279>.
			[RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
			Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation
			for Bit Index Explicit Replication (BIER) in MPLS and Non-
			MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January
			2018, <https://www.rfc-editor.org/info/rfc8296>.
	Authors' Addresses		Authors' Addresses
	Peter Psenak (editor)		Peter Psenak (editor)
	Cisco		Cisco
	Apollo Business Center		Apollo Business Center
	Mlynske nivy 43		Mlynske nivy 43
	Bratislava 821 09		Bratislava 821 09
	Slovakia		Slovakia
End of changes. 24 change blocks.
	61 lines changed or deleted		50 lines changed or added
This html diff was produced by rfcdiff 1.48. The latest version is available from http://tools.ietf.org/tools/rfcdiff/