draft-ietf-idr-bgp-flowspec-oid-03.txt		draft-ietf-idr-bgp-flowspec-oid-04.txt
	Network Working Group James Uttaro
	Internet Draft AT&T		Network Working Group J. Uttaro
	Updates: 5575 Clarence Filsfils		Internet-Draft AT&T
	Intended Status: Proposed Standard David Smith		Updates: 5575 (if approved) J. Alcaide
	Expiration Date: September 21, 2016 Juan Alcaide		Intended status: Standards Track C. Filsfils
			Expires: September 14, 2017 D. Smith
	Cisco		Cisco
	Pradosh Mohapatra		P. Mohapatra
	Sproute Networks		Sproute Networks
	March 21, 2016		March 13, 2017
	Revised Validation Procedure for BGP Flow Specifications		Revised Validation Procedure for BGP Flow Specifications
	draft-ietf-idr-bgp-flowspec-oid-03		draft-ietf-idr-bgp-flowspec-oid-04
	Abstract		Abstract
	This document describes a modification to the validation procedure		This document describes a modification to the validation procedure
	defined in RFC 5575 for the dissemination of BGP flow specifications.		defined in RFC 5575 for the dissemination of BGP flow specifications.
	RFC 5575 requires that the originator of the flow specification		RFC 5575 requires that the originator of the flow specification
	matches the originator of the best-match unicast route for the		matches the originator of the best-match unicast route for the
	destination prefix embedded in the flow specification. This allows		destination prefix embedded in the flow specification. This allows
	only BGP speakers within the data forwarding path (such as autonomous		only BGP speakers within the data forwarding path (such as autonomous
	system border routers) to originate BGP flow specifications. Though		system border routers) to originate BGP flow specifications. Though
	it is possible to disseminate such flow specifications directly from		it is possible to disseminate such flow specifications directly from
	border routers, it may be operationally cumbersome in an autonomous		border routers, it may be operationally cumbersome in an autonomous
	system with a large number of border routers having complex BGP		system with a large number of border routers having complex BGP
	policies. The modification proposed herein enables flow		policies. The modification proposed herein enables flow
	specifications to be originated from a centralized BGP route		specifications to be originated from a centralized BGP route
	controller.		controller.
	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), its areas, and its working groups. Note that		Task Force (IETF). Note that other groups may also distribute
	other groups may also distribute working documents as Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts.		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."
	The list of current Internet-Drafts can be accessed at
	http://www.ietf.org/ietf/1id-abstracts.txt.
	The list of Internet-Draft Shadow Directories can be accessed at
	http://www.ietf.org/shadow.html.
	This Internet-Draft will expire on September 21, 2016.		This Internet-Draft will expire on September 14, 2017.
	Copyright Notice		Copyright Notice
	Copyright (c) 2016 IETF Trust and the persons identified as the		Copyright (c) 2017 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(http://trustee.ietf.org/license-info) in effect on the date of		(http://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	carefully, as they describe your rights and restrictions with respect		carefully, as they describe your rights and restrictions with respect
	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
	include Simplified BSD License text as described in Section 4.e of		include Simplified BSD License text as described in Section 4.e of
	the Trust Legal Provisions and are provided without warranty as		the Trust Legal Provisions and are provided without warranty as
	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1 Specification of Requirements ...................... 3		1. Requirements Language . . . . . . . . . . . . . . . . . . . . 2
	2 Motivation ......................................... 3		2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 2
	3 Introduction ....................................... 5		3. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
	4 Revised Validation Procedure ....................... 6		4. Revised Validation Procedure . . . . . . . . . . . . . . . . 5
	5 Security Considerations ............................ 7		5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
	6 IANA Considerations ................................ 7		6. Security Considerations . . . . . . . . . . . . . . . . . . . 7
	7 Normative References ............................... 7		7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7
	8 Acknowledgements ................................... 8		8. Normative References . . . . . . . . . . . . . . . . . . . . 7
	9 Authors' Addresses ................................. 8		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
	1. Specification of Requirements		1. Requirements Language
	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 RFC 2119 [RFC2119].
	2. Motivation		2. Motivation
	Step (a) of the validation procedure in [RFC5575], section 6 is		Step (a) of the validation procedure in [RFC5575], section 6 is
	defined with the underlying assumption that the flow specification		defined with the underlying assumption that the flow specification
	NLRI traverses the same path, in the inter-domain and intra-domain		NLRI traverses the same path, in the inter-domain and intra-domain
	route distribution graph, as that of the longest-match unicast route		route distribution graph, as that of the longest-match unicast route
	for the destination prefix embedded in the flow specification.		for the destination prefix embedded in the flow specification.
	In the case of inter-domain traffic filtering, for example, the flow		In the case of inter-domain traffic filtering, for example, the flow
	specification originator at the egress border routers of ASN1 (RTR-D		specification originator at the egress border routers of ASN1 (RTR-D
	and RTR-E in figure 1) matches the EBGP neighbor that advertised the		and RTR-E in figure 1) matches the EBGP neighbor that advertised the
	longest match destination prefix (RTR-F and RTR-G respectively).		longest match destination prefix (RTR-F and RTR-G respectively).
	Similarly, at the ingress border routers of ASN1 (RTR-A and RTR-B in		Similarly, at the ingress border routers of ASN1 (RTR-A and RTR-B in
	figure 1), the flow specification originator matches the egress IBGP		figure 1), the flow specification originator matches the egress IBGP
	border routers that had advertised the unicast route for the best-		border routers that had advertised the unicast route for the best-
	match destination prefix (RTR-D and RTR-E respectively). This is true		match destination prefix (RTR-D and RTR-E respectively). This is
	even when ingress border routers select paths from different egress		true even when ingress border routers select paths from different
	border routers as best path based upon IGP distance (as an example,		egress border routers as best path based upon IGP distance (as an
	RTR-A chooses RTR-D's path as best; RTR-B chooses RTR-E as the best		example, RTR-A chooses RTR-D's path as best; RTR-B chooses RTR-E as
	path).		the best path).
	/ - - - - - - - - - - - - - -		/ - - - - - - - - - - - - - -
	| ASN1 |		| ASN1 |
	+-------+ +-------+		+-------+ +-------+
	| | | | | |		| | | | | |
	| RTR-A | | RTR-B |		| RTR-A | | RTR-B |
	| | | | | |		| | | | | |
	+-------+ +-------+		+-------+ +-------+
	| \ / |		| \ / |
	IBGP \ / IBGP		IBGP \ / IBGP
	| \ / |		| \ / |
	+-------+		+-------+
	| | | |		| | | |
	| RTR-C |		| RTR-C |
	| | RC | |		| | RC | |
	+-------+		+-------+
	| / \ |		| / \ |
	/ \		/ \
	| IBGP / \ IBGP |		| IBGP / \ IBGP |
	+-------+ +-------+		+-------+ +-------+
	| | RTR-D | | RTR-E | |		| | RTR-D | | RTR-E | |
	| | | |		| | | |
	| | | | | |		| | | | | |
	+-------+ +-------+		+-------+ +-------+
	| | | |		| | | |
	- - -|- - - - - - - - -|- - -/		- - -|- - - - - - - - -|- - -/
	| EBGP EBGP |		| EBGP EBGP |
	- - -|- - - - - - - - -|- - -/		- - -|- - - - - - - - -|- - -/
	| | | |		| | | |
	+-------+ +-------+		+-------+ +-------+
	| | | | | |		| | | | | |
	| RTR-F | | RTR-G |		| RTR-F | | RTR-G |
	| | | | | |		| | | | | |
	+-------+ +-------+		+-------+ +-------+
	| ASN2 |		| ASN2 |
	/ - - - - - - - - - - - - - -		/ - - - - - - - - - - - - - -
	Figure 1		Figure 1
	It is highly desirable that each ASN is able to protect itself		It is highly desirable that each ASN is able to protect itself
	independently from network security attacks using the BGP flow		independently from network security attacks using the BGP flow
	specification NLRI for intra-domain purposes only. Network operators		specification NLRI for intra-domain purposes only. Network operators
	often deploy a dedicated Security Operations Center (SOC) within		often deploy a dedicated Security Operations Center (SOC) within
	their ASN to monitor and detect such security attacks. To mitigate		their ASN to monitor and detect such security attacks. To mitigate
	attacks in a scalable intra-domain manner, operators require the		attacks in a scalable intra-domain manner, operators require the
	ability to originate intra-domain flow specification NLRIs from a		ability to originate intra-domain flow specification NLRIs from a
	central BGP route controller (or router reflector per [RFC4456]) that		central BGP route controller (or router reflector per [RFC4456]) that
	is not within the data forwarding plane. In this way, operators can		is not within the data forwarding plane. In this way, operators can
	direct border routers within their ASN with specific attack		direct border routers within their ASN with specific attack
	mitigation actions (drop the traffic, forward to a clean-pipe center,		mitigation actions (drop the traffic, forward to a clean-pipe center,
	etc.). To originate a flow specification NLRI, a central BGP route		etc.). To originate a flow specification NLRI, a central BGP route
	controller (or route reflector) must set itself as the originator in		controller (or route reflector) must set itself as the originator in
	the flowspec NLRI. This is necessary given the route controller is		the flowspec NLRI. This is necessary given the route controller is
	originating the flow specification not reflecting it, and to avoid		originating the flow specification not reflecting it, and to avoid
	the complexity of having to determine the egress border router whose		the complexity of having to determine the egress border router whose
	path was chosen as the best in each of the ingress border routers. It		path was chosen as the best in each of the ingress border routers.
	thus becomes necessary to modify step (a) of the RFC 5575 validation		It thus becomes necessary to modify step (a) of the RFC 5575
	procedure such that an IBGP peer that is not within the data		validation procedure such that an IBGP peer that is not within the
	forwarding plane may originate flow specification NLRIs.		data forwarding plane may originate flow specification NLRIs.
	3. Introduction		3. Introduction
	RFC 5575 defined a new BGP capability that can be used to distribute		RFC 5575 defined a new BGP capability that can be used to distribute
	traffic flow specifications amongst BGP speakers in support of		traffic flow specifications amongst BGP speakers in support of
	traffic filtering. The primary intention of RFC 5575 is to enable		traffic filtering. The primary intention of RFC 5575 is to enable
	downstream autonomous systems to signal traffic filtering policies to		downstream autonomous systems to signal traffic filtering policies to
	upstream autonomous systems. In this way, traffic is filtered closer		upstream autonomous systems. In this way, traffic is filtered closer
	to the source and the upstream autonomous system(s) avoid carrying		to the source and the upstream autonomous system(s) avoid carrying
	the traffic to the downstream autonomous system only to be discarded.		the traffic to the downstream autonomous system only to be discarded.
	RFC 5575 also enables more granular traffic filtering based upon		RFC 5575 also enables more granular traffic filtering based upon
	upper layer protocol information (e.g., protocol port numbers) as		upper layer protocol information (e.g., protocol port numbers) as
	opposed to coarse IP destination prefix-based filtering. Flow		opposed to coarse IP destination prefix-based filtering. Flow
	specification NLRIs received from a BGP peer are subject to validity		specification NLRIs received from a BGP peer are subject to validity
	checks before being considered feasible and subsequently installed		checks before being considered feasible and subsequently installed
	within the respective Adj-RIB-In. The validation procedure defined		within the respective Adj-RIB-In. The validation procedure defined
	within RFC 5575 requires that the originator of the flow		within RFC 5575 requires that the originator of the flow
	specification NLRI matches the originator of the best-match unicast		specification NLRI matches the originator of the best-match unicast
	route for the destination prefix embedded in the flow specification.		route for the destination prefix embedded in the flow specification.
	This allows only BGP speakers [RFC4271] within the data forwarding		This allows only BGP speakers [RFC4271] within the data forwarding
	path (such as autonomous system border routers) to originate BGP flow		path (such as autonomous system border routers) to originate BGP flow
	specification NLRIs. Though it is possible to disseminate such flow		specification NLRIs. Though it is possible to disseminate such flow
	specification NLRIs directly from border routers, it may be		specification NLRIs directly from border routers, it may be
	operationally cumbersome in an autonomous system with a large number		operationally cumbersome in an autonomous system with a large number
	of border routers having complex BGP policies. This document		of border routers having complex BGP policies. This document
	describes a modification to the RFC 5575 validation procedure		describes a modification to the RFC 5575 validation procedure
	allowing flow specification NLRIs to be originated from a centralized		allowing flow specification NLRIs to be originated from a centralized
	BGP route controller within the local autonomous system that is		BGP route controller within the local autonomous system that is
	neither in the data forwarding path nor serving as a BGP route		neither in the data forwarding path nor serving as a BGP route
	reflector [RFC4456]. While the proposed modification cannot be used		reflector [RFC4456]. While the proposed modification cannot be used
	for inter-domain coordination of traffic filtering, it greatly		for inter-domain coordination of traffic filtering, it greatly
	simplifies distribution of intra-domain traffic filtering policies in		simplifies distribution of intra-domain traffic filtering policies in
	an autonomous system with a large number of border routers having		an autonomous system with a large number of border routers having
	complex BGP policies. By relaxing the validation procedure for IBGP,		complex BGP policies. By relaxing the validation procedure for IBGP,
	the proposed modification allows flow specifications to be		the proposed modification allows flow specifications to be
	distributed in a standard and scalable manner throughout an		distributed in a standard and scalable manner throughout an
	autonomous system.		autonomous system.
	4. Revised Validation Procedure		4. Revised Validation Procedure
	Step (a) of the validation procedure specified in RFC 5575, section 6		Step (a) of the validation procedure specified in RFC 5575, section 6
	is redefined as follows:		is redefined as follows:
	a) One of the following conditions MUST hold true:		a. One of the following conditions MUST hold true.
	o The originator of the flow specification matches the
	originator of the best-match unicast route for the
	destination prefix embedded in the flow specification.
	o The AS_PATH and AS4_PATH attribute of the flow
	specification are empty.
	o The AS_PATH and AS4_PATH attribute of the flow
	specification does not contain AS_SET and AS_SEQUENCE
	segments.
	An empty AS_PATH and AS4_PATH attribute indicates per [RFC4271] that		* The originator of the flow specification matches the
	the flow specification NLRI originated in the same autonomous system		originator of the best-match unicast route for the destination
	as the local BGP speaker. Similarly, lack of AS_SET and AS_SEQUENCE		prefix embedded in the flow specification.
	segments within an AS_PATH and AS4_PATH attribute that is not empty
	indicates that the flow specification NLRI originated in the same		* The AS_PATH attribute of the flow specification does not
	autonomous system as the local BGP speaker but that the autonomous		contain AS_SET and AS_SEQUENCE segments.
	system includes a BGP confederation [RFC5065]. With this proposed
	modification to the RFC 5575 validation procedure, it is now possible		An AS_PATH without AS_SET and AS_SEQUENCE segments indicates that the
	for an IBGP peer that is not within the data forwarding path to		flow specification was originated inside the local AS [RFC4271] or
	originate flow specification NLRIs. This applies with and without the		inside the local confederation (in the case that the local AS belongs
	presence of a BGP confederation within the autonomous system.		to a confederation of ASes) [RFC5065]. With this modification to the
			RFC 5575 validation procedure, it is now possible for an IBGP peer
			that is not within the data forwarding path to originate flow
			specification NLRIs. This applies whether the AS belongs or not to a
			confederation of ASes. Checking the (newly introduced) second
			condition above MAY be disabled by configuration on a BGP speaker.
			However, it SHOULD be enabled by default. Disabling the condition
			may be a good practice when the administrator knows with certainty
			that there are not flow specification NLRI originated inside the
			local AS (or local confederation). Optionally, an implementation
			could be configured to allow only flow specification NLRIs containing
			only a subset of ASes. This could be useful, for example, with
			networks that consist of multiple ASes that operate under the same
			administrative domain.
	Further, RFC 5575 states that "BGP (flow specification)		Further, RFC 5575 states that "BGP (flow specification)
	implementations MUST also enforce that AS_PATH attribute of a route		implementations MUST also enforce that AS_PATH attribute of a route
	received via the External Border Gateway Protocol (eBGP) contains the		received via the External Border Gateway Protocol (EBGP) contains the
	neighboring AS in the left-most position of the AS_PATH attribute".		neighboring AS in the left-most position of the AS_PATH attribute".
	This rule is not valid for all topologies. For example, it prevents		This rule is not valid for all topologies. For example, it prevents
	exchange of BGP flow specification NLRIs at Internet exchanges with		the exchange of BGP flow specification NLRIs at Internet exchanges
	BGP route servers. Therefore, this document also redefines the RFC		with BGP route servers. Therefore, this document also redefines the
	5575 AS_PATH and AS4_PATH validation procedure referenced above as		RFC 5575 AS_PATH validation procedure referenced above as follows.
	follows.
	BGP flow specification implementations MUST enforce that the last AS		BGP flow specification implementations MUST enforce that the last AS
	added within the AS_PATH and AS4_PATH attribute of a EBGP learned		added within the AS_PATH attribute of a EBGP learned flow
	flow specification NLRI MUST match the last AS added within the		specification NLRI MUST match the last AS added within the AS_PATH
	AS_PATH and AS4_PATH attribute of the best-match unicast route for		attribute of the best-match unicast route for the destination prefix
	the destination prefix embedded in the flow specification. This		embedded in the flow specification. This proposed modification
	proposed modification enables the exchange of BGP flow specification		enables the exchange of BGP flow specification NLRIs at Internet
	NLRIs at Internet exchanges with BGP route servers while at the same		exchanges with BGP route servers while at the same time, for security
	time, for security reasons, prevents an EBGP peer from advertising an		reasons, prevents an EBGP peer from advertising an inter-domain flow
	inter-domain flow specification for a destination prefix that it does		specification for a destination prefix that it does not provide
	not provide reachability information for. Note, comparing only the		reachability information for. Note, comparing only the last ASes is
	last ASNs is sufficient for EBGP learned flow specification NLRIs.		sufficient for EBGP learned flow specification NLRIs. Requiring a
			full AS_PATH match would limit origination of inter-domain flow
			specifications to the origin (or first) AS of the best-match unicast
			route for the destination prefix embedded in the flow specification
			only. As such, a full AS_PATH validity check may prevent transit
			ASes from originating inter-domain flow specifications which is not
			desirable.
	Requiring a full AS_PATH and AS4_PATH match would limit origination		This document also clarifies proper handling when the BGP flow
	of inter-domain flow specifications to the origin (or first) AS of		specification does not embed a destination prefix component. The
	the best-match unicast route for the destination prefix embedded in		default behavior SHOULD be not to perform any validation procedure.
	the flow specification only. As such, a full AS_PATH and AS4_PATH		Further, support for two-octet AS number space is out of the scope of
	validity check may prevent transit ASNs from originating inter-domain		this document.
	flow specifications which is not desirable.
	5. Security Considerations		In this context, AS_PATH attribute is defined as the reconstructed AS
			Path information (by combining AS_PATH and AS4_PATH attributes, if
			the BGP speaker is a NEW speaker and receives the route from an OLD
			speaker), according to section 4.2.3 of RFC 6793.
			RFC 5575 references "the best-match unicast route for the destination
			prefix embedded in the flow specification". For clarity, this route
			is defined hereby as the best path of the unicast network that covers
			destination prefix embedded in the flow specification with the longer
			prefix-length. In other words, we consider only the best-match
			network and we do not consider unicast non-best paths (even if it is
			received from the same peer than the flowspec route).
			Note that, per RFC 5575, originator may refer to the BGP
			ORIGINATOR_ID attribute or the transport address of the peer from
			which we received the update. If the later, a network must be
			designed so it has a congruent topology. Otherwise, using two
			peering sessions between the same pair of BGP speakers, one for
			unicast and one for flowspec, will cause the flowspec validation
			procedure to fail. Consider, for example, the case where a BGP route
			reflector receives the NLRIs from a route reflector client, thus not
			receiving the ORIGINATOR_ID attribute. If the speaker belongs to a
			confederation [RFC5065] and we are receiving a flowspec route from
			different peers than its best match unicast route, the flowspec
			validation procedure will fail as well. Consider also a
			misconfiguration where flowspec address-family is not configured for
			a particular peering between different member-AS (but it is
			configured for unicast). Even if we receive the flowspec route via a
			redundant peer, we may receive the unicast route and the flowspec
			from different peers, and thus flowspec validation will fail. With
			the (newly introduced) second condition above applied, uncongruent
			topologies are supported.
			5. IANA Considerations
			This memo includes no request to IANA.
			6. Security Considerations
	No new security issues are introduced by relaxing the validation		No new security issues are introduced by relaxing the validation
	procedure for IBGP learned flow specifications. With this proposal,		procedure for IBGP learned flow specifications. With this proposal,
	the security characteristics of BGP flow specifications remain		the security characteristics of BGP flow specifications remain
	equivalent to the existing security properties of BGP unicast		equivalent to the existing security properties of BGP unicast
	routing. Traffic flow specifications learned from IBGP peers are		routing. Traffic flow specifications learned from IBGP peers are
	trusted, hence, its not required to validate that the originator of		trusted, hence, it is not required to validate that the originator of
	an intra-domain traffic flow specification matches the originator of		an intra-domain traffic flow specification matches the originator of
	the best-match unicast route for the flow destination prefix.		the best-match unicast route for the flow destination prefix.
	Conversely, this proposal continues to enforce the validation		Conversely, this proposal continues to enforce the validation
	procedure for EBGP learned traffic flow specifications. In this way,		procedure for EBGP learned traffic flow specifications. In this way,
	the security properties of RFC 5575 are maintained such that an EBGP		the security properties of RFC 5575 are maintained such that an EBGP
	peer cannot cause a denial-of-service attack by advertising an		peer cannot cause a denial-of-service attack by advertising an inter-
	inter-domain flow specification for a destination prefix that it does		domain flow specification for a destination prefix that it does not
	not provide reachability information for.		provide reachability information for.
	6. IANA Considerations
	This document has no actions for IANA.		7. Acknowledgements
	7. Normative References		The authors would like to thank Han Nguyen for his direction on this
			work as well as Waqas Alam, Keyur Patel, Robert Raszuk, Eric Rosen
			and Shyam Sethuram for their review comments.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		8. Normative References
	Requirement Levels", BCP 14, RFC 2119, March 1997.
	[RFC4271] Rekhter, Y., Li, T., and Hares, S., "A Border Gateway		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Protocol 4 (BGP-4)", RFC 4271, March 2006.		Requirement Levels", BCP 14, RFC 2119,
			DOI 10.17487/RFC2119, March 1997,
			<http://www.rfc-editor.org/info/rfc2119>.
	[RFC4456] Bates, T., Chen, E., and Chandra, R., "BGP Route		[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
	Reflection: An Alternative to Full Mesh Internal BGP (IBGP)", RFC		Border Gateway Protocol 4 (BGP-4)", RFC 4271,
	4456, April 2006.		DOI 10.17487/RFC4271, January 2006,
			<http://www.rfc-editor.org/info/rfc4271>.
	[RFC5065] Traina, P., McPherson, D., and Scudder, J., "Autonomous		[RFC4456] Bates, T., Chen, E., and R. Chandra, "BGP Route
	System Confederations for BGP", August 2007.		Reflection: An Alternative to Full Mesh Internal BGP
			(IBGP)", RFC 4456, DOI 10.17487/RFC4456, April 2006,
			<http://www.rfc-editor.org/info/rfc4456>.
	[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,		[RFC5065] Traina, P., McPherson, D., and J. Scudder, "Autonomous
	and McPherson, D., "Dissemination of Flow Specification Rules", RFC		System Confederations for BGP", RFC 5065,
	5575, August 2009.		DOI 10.17487/RFC5065, August 2007,
			<http://www.rfc-editor.org/info/rfc5065>.
	8. Acknowledgements		[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
			and D. McPherson, "Dissemination of Flow Specification
			Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
			<http://www.rfc-editor.org/info/rfc5575>.
	The authors would like to thank Han Nguyen for his direction on this		[RFC6793] Vohra, Q. and E. Chen, "BGP Support for Four-Octet
	work as well as Waqas Alam, Keyur Patel, Robert Raszuk, Eric Rosen		Autonomous System (AS) Number Space", RFC 6793,
	and Shyam Sethuram for their review comments.		DOI 10.17487/RFC6793, December 2012,
			<http://www.rfc-editor.org/info/rfc6793>.
	9. Authors' Addresses		Authors' Addresses
	James Uttaro		James Uttaro
	AT&T		AT&T
	200 S. Laurel Avenue		200 S. Laurel Ave
	Middletown, NJ 07748		Middletown, NJ 07748
	USA		USA
	Email: ju1738@att.com		Email: ju1738@att.com
	Juan Alcaide		Juan Alcaide
	Cisco		Cisco
	7100 Kit Creek Road		7100 Kit Creek Road
	Research Triangle Park, NC 27709		Research Triangle Park, NC 27709
	USA		USA
	Email: jalcaide@cisco.com		Email: jalcaide@cisco.com
	Clarence Filsfils		Clarence Filsfils
	Cisco		Cisco
	Brussels 1000
	BE
	Email: cf@cisco.com		Email: cf@cisco.com
	David Smith		David Smith
	Cisco		Cisco
	111 Wood Avenue South		111 Wood Ave South
	Iselin, NJ 08830		Iselin, NJ 08830
	USA		USA
	Email: djsmith@cisco.com		Email: djsmith@cisco.com
	Pradosh Mohapatra		Pradosh Mohapatra
	Sproute Networks		Sproute Networks
	Email: mpradosh@yahoo.com		Email: mpradosh@yahoo.com
End of changes. 63 change blocks.
	187 lines changed or deleted		236 lines changed or added
This html diff was produced by rfcdiff 1.45. The latest version is available from http://tools.ietf.org/tools/rfcdiff/