< draft-ietf-grow-bmp-adj-rib-out-05.txt.orig		draft-ietf-grow-bmp-adj-rib-out-05.txt >
	skipping to change at page 2, line 31 ¶		skipping to change at page 2, line 31 ¶
	6.1. Route Monitoring and Route Mirroring . . . . . . . . . . 5		6.1. Route Monitoring and Route Mirroring . . . . . . . . . . 5
	6.2. Statistics Report . . . . . . . . . . . . . . . . . . . . 5		6.2. Statistics Report . . . . . . . . . . . . . . . . . . . . 5
	6.3. Peer Down and Up Notifications . . . . . . . . . . . . . 6		6.3. Peer Down and Up Notifications . . . . . . . . . . . . . 6
	6.3.1. Peer Up Information . . . . . . . . . . . . . . . . . 6		6.3.1. Peer Up Information . . . . . . . . . . . . . . . . . 6
	7. Other Considerations . . . . . . . . . . . . . . . . . . . . 6		7. Other Considerations . . . . . . . . . . . . . . . . . . . . 6
	7.1. Peer and Update Groups . . . . . . . . . . . . . . . . . 6		7.1. Peer and Update Groups . . . . . . . . . . . . . . . . . 6
	8. Security Considerations . . . . . . . . . . . . . . . . . . . 7		8. Security Considerations . . . . . . . . . . . . . . . . . . . 7
	9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7		9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
	9.1. BMP Peer Flags . . . . . . . . . . . . . . . . . . . . . 7		9.1. BMP Peer Flags . . . . . . . . . . . . . . . . . . . . . 7
	9.2. BMP Statistics Types . . . . . . . . . . . . . . . . . . 7		9.2. BMP Statistics Types . . . . . . . . . . . . . . . . . . 7
	9.3. Peer UP Information TLV . . . . . . . . . . . . . . . . . 8		9.3. Peer Up Information TLV . . . . . . . . . . . . . . . . . 8
	10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8		10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
	10.1. Normative References . . . . . . . . . . . . . . . . . . 8		10.1. Normative References . . . . . . . . . . . . . . . . . . 8
	10.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 8		10.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 9		Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 9
	Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 9		Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 9
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
	1. Introduction		1. Introduction
	BGP Monitoring Protocol (BMP) defines monitoring of the received		BGP Monitoring Protocol (BMP) defines monitoring of the received
	(e.g. Adj-RIB-In) Routing Information Bases (RIBs) per peer. The		(e.g., Adj-RIB-In) Routing Information Bases (RIBs) per peer. The
	Adj-RIB-In pre-policy conveys to a BMP receiver all RIB data before		Adj-RIB-In pre-policy conveys to a BMP receiver all RIB data before
	any policy has been applied. The Adj-RIB-In post-policy conveys to a		any policy has been applied. The Adj-RIB-In post-policy conveys to a
	BMP receiver all RIB data after policy filters and/or modifications		BMP receiver all RIB data after policy filters and/or modifications
	have been applied. An example of pre-policy verses post-policy is		have been applied. An example of pre-policy verses post-policy is
	when an inbound policy applies attribute modification or filters.		when an inbound policy applies attribute modification or filters.
	Pre-policy would contain information prior to the inbound policy		Pre-policy would contain information prior to the inbound policy
	changes or filters of data. Post policy would convey the changed		changes or filters of data. Post policy would convey the changed
	data or would not contain the filtered data.		data or would not contain the filtered data.
	Monitoring the received updates that the router received before any		Monitoring the received updates that the router received before any
	policy has been applied is the primary level of monitoring for most		policy has been applied is the primary level of monitoring for most
	use-cases. Inbound policy validation and auditing is the primary		use-cases. Inbound policy validation and auditing is the primary
	use-case for enabling post-policy monitoring.		use-case for enabling post-policy monitoring.
	In order for a BMP receiver to receive any BGP data, the BMP sender		In order for a BMP receiver to receive any BGP data, the BMP sender
	(e.g. router) needs to have an established BGP peering session and		(e.g., router) needs to have an established BGP peering session and
	actively be receiving updates for an Adj-RIB-In.		actively be receiving updates for an Adj-RIB-In.
	Being able to only monitor the Adj-RIB-In puts a restriction on what		Being able to only monitor the Adj-RIB-In puts a restriction on what
	data is available to BMP receivers via BMP senders (e.g. routers).		data is available to BMP receivers via BMP senders (e.g., routers).
	This is an issue when the receiving end of the BGP peer is not		This is an issue when the receiving end of the BGP peer is not
	enabled for BMP or when it is not accessible for administrative		enabled for BMP or when it is not accessible for administrative
	reasons. For example, a service provider advertises prefixes to a		reasons. For example, a service provider advertises prefixes to a
	customer, but the service provider cannot see what it advertises via		customer, but the service provider cannot see what it advertises via
	BMP. Asking the customer to enable BMP and monitoring of the Adj-		BMP. Asking the customer to enable BMP and monitoring of the Adj-
	RIB- In is not feasible.		RIB-In is not feasible.
	This document updates the BGP Monitoring Protocol (BMP) RFC 7854		This document updates the BGP Monitoring Protocol (BMP) RFC 7854
	[RFC7854] peer header by adding a new flag to distinguish Adj-RIB-In		[RFC7854] peer header by adding a new flag to distinguish Adj-RIB-In
	verses Adj-RIB-Out.		verses Adj-RIB-Out.
	Adding Adj-RIB-Out provides the ability for a BMP sender to send to a		Adding Adj-RIB-Out provides the ability for a BMP sender to send to a
	BMP receiver what it advertises to BGP peers, which can be used for		BMP receiver what it advertises to BGP peers, which can be used for
	outbound policy validation and to monitor RIBs that were advertised.		outbound policy validation and to monitor routes that were advertised.
	2. Terminology		2. Terminology
	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", "NOT RECOMMENDED", "MAY", and
	document are to be interpreted as described in RFC 2119 [RFC2119].		"OPTIONAL" in this document are to be interpreted as described in BCP
			14 [RFC2119] [RFC8174] when, and only when, they appear in all
			capitals, as shown here.
	3. Definitions		3. Definitions
	o Adj-RIB-Out: As defined in [RFC4271], "The Adj-RIBs-Out contains		o Adj-RIB-Out: As defined in [RFC4271], "The Adj-RIBs-Out contains
	the routes for advertisement to specific peers by means of the		the routes for advertisement to specific peers by means of the
	local speaker's UPDATE messages."		local speaker's UPDATE messages."
	o Pre-Policy Adj-RIB-Out: The result before applying the outbound		o Pre-Policy Adj-RIB-Out: The result before applying the outbound
	policy to an Adj-RIB-Out. This normally would match what is in the		policy to an Adj-RIB-Out. This normally would match what is in the
	local RIB.		local RIB.
	skipping to change at page 4, line 21 ¶		skipping to change at page 4, line 21 ¶
	+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+
	|V|L|A|O| Resv |		|V|L|A|O| Resv |
	+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+
	o The O flag indicates Adj-RIB-In if set to 0 and Adj-RIB-Out if set		o The O flag indicates Adj-RIB-In if set to 0 and Adj-RIB-Out if set
	to 1.		to 1.
	The existing flags are defined in section 4.2 [RFC7854] and the		The existing flags are defined in section 4.2 [RFC7854] and the
	remaining bits are reserved for future use. They SHOULD be		remaining bits are reserved for future use. They SHOULD be
	transmitted as 0 and their values MUST be ignored on receipt. The		transmitted as 0 and their values MUST be ignored on receipt. The
	following fields in Per-Peer Header are redefined:		following fields in the Per-Peer Header are redefined:
	o Peer Address: The remote IP address associated with the TCP		o Peer Address: The remote IP address associated with the TCP
	session over which the encapsulated PDU is sent.		session over which the encapsulated PDU is sent.
	o Peer AS: The Autonomous System number of the peer from which the		o Peer AS: The Autonomous System number of the peer from which the
	encapsulated PDU was sent.		encapsulated PDU was sent.
	o Peer BGP ID: The BGP Identifier of the peer from which the		o Peer BGP ID: The BGP Identifier of the peer from which the
	encapsulated PDU was sent.		encapsulated PDU was sent.
	5. Adj-RIB-Out		5. Adj-RIB-Out
	5.1. Post-Policy		5.1. Post-Policy
	The primary use-case in monitoring Adj-RIB-Out is to monitor the		The primary use-case in monitoring Adj-RIB-Out is to monitor the
	updates transmitted to the BGP peer after outbound policy has been		updates transmitted to a BGP peer after outbound policy has been
	applied. These updates reflect the result after modifications and		applied. These updates reflect the result after modifications and
	filters have been applied (e.g. Adj-RIB-Out Post-Policy). Some		filters have been applied (e.g., Adj-RIB-Out Post-Policy). Some
	attributes are set when the BGP message is transmitted, such as next-		attributes are set when the BGP message is transmitted, such as next-
	hop. Adj-RIB-Out Post-Policy MUST convey what is actually		hop. Adj-RIB-Out Post-Policy MUST convey what is actually
	transmitted to the peer, next-hop and any attribute set during		transmitted to the peer, next-hop and any attributes set during
	transmission should also be set and transmitted to the BMP receiver.		transmission should also be set and transmitted to the BMP receiver.
	The L flag MUST be set to 1 to indicate post-policy.		The L flag MUST be set to 1 to indicate post-policy.
	5.2. Pre-Policy		5.2. Pre-Policy
	Similarly to Adj-RIB-In policy validation, pre-policy Adj-RIB-Out can		Similarly to Adj-RIB-In policy validation, pre-policy Adj-RIB-Out can
	be used to validate and audit outbound policies. For example, a		be used to validate and audit outbound policies. For example, a
	comparison between pre-policy and post-policy can be used to validate		comparison between pre-policy and post-policy can be used to validate
	the outbound policy.		the outbound policy.
	Depending on BGP peering session type (IBGP, IBGP route reflector		Depending on BGP peering session type (IBGP, IBGP route reflector
	client, EBGP, BGP confederations, Route Server Client) the candidate		client, EBGP, BGP confederation, Route Server Client) the candidate
	routes that make up the Pre-Policy Adj-RIB-Out do not contain all		routes that make up the Pre-Policy Adj-RIB-Out do not contain all
	local-rib routes. Pre-Policy Adj-RIB-Out conveys only routes that		local-rib routes. Pre-Policy Adj-RIB-Out conveys only routes that
	are available based on the peering type. Post-Policy represents the		are available based on the peering type. Post-Policy represents the
	filtered/changed routes from the available routes.		filtered/changed routes from the available routes.
	Some attributes are set only during transmission of the BGP message,		Some attributes are set only during transmission of the BGP message,
	ie. Post-Policy. It is common that next-hop may be null, loopback,		i.e., Post-Policy. It is common that next-hop may be null, loopback,
	or similar during this phase. All mandatory attributes, such as		or similar during this phase. All mandatory attributes, such as
	next-hop, MUST be either ZERO or have an empty length if they are		next-hop, MUST be either ZERO or have an empty length if they are
	unknown at the Pre-Policy phase. The BMP receiver will treat zero or		unknown at the Pre-Policy phase completion. The BMP receiver will
	empty mandatory attributes as self originated.		treat zero or empty mandatory attributes as self-originated.
	The L flag MUST be set to 0 to indicate pre-policy.		The L flag MUST be set to 0 to indicate pre-policy.
	6. BMP Messages		6. BMP Messages
	Many BMP messages have a per-peer header but some are not applicable		Many BMP messages have a per-peer header but some are not applicable
	to Adj-RIB-In or Adj-RIB-Out monitoring. Unless otherwise defined,		to Adj-RIB-In or Adj-RIB-Out monitoring. Unless otherwise defined,
	the O flag should be set to 0 in the per-peer header in BMP messages.		the O flag should be set to 0 in the per-peer header in BMP messages.
	6.1. Route Monitoring and Route Mirroring		6.1. Route Monitoring and Route Mirroring
	The O flag MUST be set accordingly to indicate if the route monitor		The O flag MUST be set accordingly to indicate if the route monitor
	or route mirroring message conveys Adj-RIB-In or Adj-RIB-Out.		or route mirroring message conveys Adj-RIB-In or Adj-RIB-Out.
	6.2. Statistics Report		6.2. Statistics Report
	Statistics report message has Stat Type field to indicate the		The Statistics report message has a Stat Type field to indicate the
	statistic carried in the Stat Data field. Statistics report messages		statistic carried in the Stat Data field. Statistics report messages
	are not specific to Adj-RIB-In or Adj-RIB-Out and MUST have the O		are not specific to Adj-RIB-In or Adj-RIB-Out and MUST have the O
	flag set to zero. The O flag SHOULD be ignored by the BMP receiver.		flag set to zero. The O flag SHOULD be ignored by the BMP receiver.
	The following new statistic types are added:		The following new statistic types are added:
	o Stat Type = 14: (64-bit Gauge) Number of routes in Adj-RIBs-Out		o Stat Type = 14: (64-bit Gauge) Number of routes in Adj-RIBs-Out
	Pre-Policy.		Pre-Policy.
	o Stat Type = 15: (64-bit Gauge) Number of routes in Adj-RIBs-Out		o Stat Type = 15: (64-bit Gauge) Number of routes in Adj-RIBs-Out
	skipping to change at page 6, line 12 ¶		skipping to change at page 6, line 12 ¶
	Identifier (AFI), 1-byte Subsequent Address Family Identifier		Identifier (AFI), 1-byte Subsequent Address Family Identifier
	(SAFI), followed by a 64-bit Gauge.		(SAFI), followed by a 64-bit Gauge.
	o Stat Type = 17: Number of routes in per-AFI/SAFI Adj-RIB-Out Post-		o Stat Type = 17: Number of routes in per-AFI/SAFI Adj-RIB-Out Post-
	Policy. The value is structured as: 2-byte Address Family		Policy. The value is structured as: 2-byte Address Family
	Identifier (AFI), 1-byte Subsequent Address Family Identifier		Identifier (AFI), 1-byte Subsequent Address Family Identifier
	(SAFI), followed by a 64-bit Gauge.		(SAFI), followed by a 64-bit Gauge.
	6.3. Peer Down and Up Notifications		6.3. Peer Down and Up Notifications
	PEER UP and DOWN notifications convey BGP peering session state to		Peer Up and Down notifications convey BGP peering session state to
	BMP receivers. The state is independent of whether or not route		BMP receivers. The state is independent of whether or not route
	monitoring or route mirroring messages will be sent for Adj-RIB-In,		monitoring or route mirroring messages will be sent for Adj-RIB-In,
	Adj-RIB-Out, or both. BMP receiver implementations SHOULD ignore the		Adj-RIB-Out, or both. BMP receiver implementations SHOULD ignore the
	O flag in PEER UP and DOWN notifications. BMP receiver		O flag in Peer Up and Down notifications. BMP receiver
	implementations MUST use the per-peer header O flag in route		implementations MUST use the per-peer header O flag in route
	monitoring and mirroring messages in order to identify if the message		monitoring and mirroring messages to identify if the message
	is for Adj-RIB-In or Adj-RIB-Out.		is for Adj-RIB-In or Adj-RIB-Out.
	6.3.1. Peer Up Information		6.3.1. Peer Up Information
	The following peer UP information TLV types are added:		The following Peer Up message Information TLV type is added:
	o Type = 4: Admin Label. The Information field contains a free-form		o Type = 4: Admin Label. The Information field contains a free-form
	UTF-8 string whose length is given by the Information Length		UTF-8 string whose length is given by the Information Length
	field. The value is administratively assigned. There is no		field. The value is administratively assigned. There is no
	requirement to terminate the string with null or any other		requirement to terminate the string with null or any other
	character.		character.
	Multiple admin labels can be included in the Peer UP. When		Multiple admin labels can be included in the Peer Up notification. When
	multiple admin labels are included the BMP receiver MUST preserve		multiple admin labels are included the BMP receiver MUST preserve
	the order.		their order.
	The TLV is optional.		The TLV is optional.
	7. Other Considerations		7. Other Considerations
	7.1. Peer and Update Groups		7.1. Peer and Update Groups
	Peer and update groups are used to group updates shared by many		Peer and update groups are used to group updates shared by many
	peers. This is a level of efficiency in the implementation, not a		peers. This is a level of efficiency in implementations, not a
	true representation of what is conveyed to a peer in either Pre-		true representation of what is conveyed to a peer in either Pre-
	Policy or Post-Policy.		Policy or Post-Policy.
	One of the use-cases to monitor Adj-RIB-Out Post-Policy is to		One of the use-cases to monitor Adj-RIB-Out Post-Policy is to
	validate and continually ensure the egress updates match what is		validate and continually ensure the egress updates match what is
	expected. For example, wholesale peers should never have routes with		expected. For example, wholesale peers should never have routes with
	community X:Y sent to them. In this use-case, there may be hundreds		community X:Y sent to them. In this use-case, there may be hundreds
	of wholesale peers but a single peer could have represented the		of wholesale peers but a single peer could have represented the
	group.		group.
	From a BMP perspective, this should be simple to include a group name		From a BMP perspective, this should be simple to include a group name
	in the PEER UP, but it is more complex than that. BGP		in the Peer Up, but it is more complex than that. BGP
	implementations have evolved to provide comprehensive and structured		implementations have evolved to provide comprehensive and structured
	policy grouping, such as session, afi/safi, and template based group		policy grouping, such as session, AFI/SAFI, and template-based group
	policy inheritances.		policy inheritances.
	This level of structure and inheritance of polices does not provide a		This level of structure and inheritance of polices does not provide a
	simple peer group name or ID, such as wholesale peer.		simple peer group name or ID, such as wholesale peer.
	Instead of requiring a group name to be used, a new administrative		Instead of requiring a group name to be used, a new administrative
	label informational TLV (Section 6.3.1) is added to the Peer UP		label informational TLV (Section 6.3.1) is added to the Peer Up
	message. These labels have administrative scope relevance. For		message. These labels have administrative scope relevance. For
	example, labels "type=wholesale" and "region=west" could be used to		example, labels "type=wholesale" and "region=west" could be used to
	monitor expected policies.		monitor expected policies.
	Configuration and assignment of labels to peers is BGP implementation		Configuration and assignment of labels to peers is BGP implementation
	specific.		specific.
	8. Security Considerations		8. Security Considerations
	It is not believed that this document adds any additional security		It is not believed that this document adds any additional security
	considerations.		considerations.
	9. IANA Considerations		9. IANA Considerations
	This document requests that IANA assign the following new parameters		This document requests that IANA assign the following new parameters
	to the BMP parameters name space [1].		to the BMP parameters name space [1].
	9.1. BMP Peer Flags		9.1. BMP Peer Flags
	This document defines the following new per-peer header flags		This document defines the following per-peer header flags
	(Section 4):		(Section 4):
	o Flag 3 as O flag: The O flag indicates Adj-RIB-In if set to 0 and		o Flag 3 as O flag: The O flag indicates Adj-RIB-In if set to 0 and
	Adj-RIB-Out if set to 1.		Adj-RIB-Out if set to 1.
	9.2. BMP Statistics Types		9.2. BMP Statistics Types
	This document defines four new statistic types for statistics		This document defines four statistic types for statistics
	reporting (Section 6.2):		reporting (Section 6.2):
	o Stat Type = 14: (64-bit Gauge) Number of routes in Adj-RIBs-Out		o Stat Type = 14: (64-bit Gauge) Number of routes in Adj-RIBs-Out
	Pre-Policy.		Pre-Policy.
	o Stat Type = 15: (64-bit Gauge) Number of routes in Adj-RIBs-Out		o Stat Type = 15: (64-bit Gauge) Number of routes in Adj-RIBs-Out
	Post-Policy.		Post-Policy.
	o Stat Type = 16: Number of routes in per-AFI/SAFI Adj-RIB-Out Pre-		o Stat Type = 16: Number of routes in per-AFI/SAFI Adj-RIB-Out Pre-
	Policy. The value is structured as: 2-byte Address Family		Policy. The value is structured as: 2-byte Address Family
	Identifier (AFI), 1-byte Subsequent Address Family Identifier		Identifier (AFI), 1-byte Subsequent Address Family Identifier
	(SAFI), followed by a 64-bit Gauge.		(SAFI), followed by a 64-bit Gauge.
	o Stat Type = 17: Number of routes in per-AFI/SAFI Adj-RIB-Out Post-		o Stat Type = 17: Number of routes in per-AFI/SAFI Adj-RIB-Out Post-
	Policy. The value is structured as: 2-byte Address Family		Policy. The value is structured as: 2-byte Address Family
	Identifier (AFI), 1-byte Subsequent Address Family Identifier		Identifier (AFI), 1-byte Subsequent Address Family Identifier
	(SAFI), followed by a 64-bit Gauge.		(SAFI), followed by a 64-bit Gauge.
	9.3. Peer UP Information TLV		9.3. Peer Up Information TLV
	This document defines the following new BMP PEER UP informational		This document defines the following BMP Peer Up Information
	message TLV types (Section 6.3.1):		TLV type (Section 6.3.1):
	o Type = 4: Admin Label. The Information field contains a free-form		o Type = 4: Admin Label. The Information field contains a free-form
	UTF-8 string whose length is given by the Information Length		UTF-8 string whose length is given by the Information Length
	field. The value is administratively given by the Information		field. The value is administratively given by the Information
	Length field. The value is administratively assigned. There is		Length field. The value is administratively assigned. There is
	no requirement to terminate the string with null or any other		no requirement to terminate the string with null or any other
	character.		character.
	10. References		10. References
	skipping to change at page 8, line 46 ¶		skipping to change at page 8, line 46 ¶
	[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A		[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
	Border Gateway Protocol 4 (BGP-4)", RFC 4271,		Border Gateway Protocol 4 (BGP-4)", RFC 4271,
	DOI 10.17487/RFC4271, January 2006,		DOI 10.17487/RFC4271, January 2006,
	<https://www.rfc-editor.org/info/rfc4271>.		<https://www.rfc-editor.org/info/rfc4271>.
	[RFC7854] Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP		[RFC7854] Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP
	Monitoring Protocol (BMP)", RFC 7854,		Monitoring Protocol (BMP)", RFC 7854,
	DOI 10.17487/RFC7854, June 2016,		DOI 10.17487/RFC7854, June 2016,
	<https://www.rfc-editor.org/info/rfc7854>.		<https://www.rfc-editor.org/info/rfc7854>.
			[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
			2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
			May 2017, <https://www.rfc-editor.org/info/rfc8174>.
	10.2. URIs		10.2. URIs
	[1] https://www.iana.org/assignments/bmp-parameters/bmp-		[1] https://www.iana.org/assignments/bmp-parameters/bmp-
	parameters.xhtml		parameters.xhtml
	Acknowledgements		Acknowledgements
	The authors would like to thank John Scudder for his valuable input.		The authors would like to thank John Scudder for his valuable input.
	Contributors		Contributors
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