draft-ietf-idr-bgp-open-policy-05.txt   draft-ietf-idr-bgp-open-policy-06.txt 
Network Working Group A. Azimov Network Working Group A. Azimov
Internet-Draft E. Bogomazov Internet-Draft E. Bogomazov
Intended status: Standards Track Qrator Labs Intended status: Standards Track Qrator Labs
Expires: August 19, 2019 R. Bush Expires: January 9, 2020 R. Bush
Internet Initiative Japan Internet Initiative Japan & Arrcus
K. Patel K. Patel
Arrcus, Inc. Arrcus, Inc.
K. Sriram K. Sriram
US NIST US NIST
February 15, 2019 July 8, 2019
Route Leak Prevention using Roles in Update and Open messages Route Leak Prevention using Roles in Update and Open messages
draft-ietf-idr-bgp-open-policy-05 draft-ietf-idr-bgp-open-policy-06
Abstract Abstract
Route Leaks are the propagation of BGP prefixes which violate Route Leaks are the propagation of BGP prefixes which violate
assumptions of BGP topology relationships; e.g. passing a route assumptions of BGP topology relationships; e.g. passing a route
learned from one peer to another peer or to a transit provider, learned from one peer to another peer or to a transit provider,
passing a route learned from one transit provider to another transit passing a route learned from one transit provider to another transit
provider or to a peer. Today, approaches to leak prevention rely on provider or to a peer. Today, approaches to leak prevention rely on
marking routes according to operator configuration options, with no marking routes by operator configuration, with no check that the
check that the configuration corresponds to that of the BGP neighbor, configuration corresponds to that of the BGP neighbor, or enforcement
or enforcement that the two BGP speakers agree on the relationship. that the two BGP speakers agree on the relationship. This document
This document enhances BGP Open to establish agreement of the (peer, enhances BGP OPEN to establish agreement of the (peer, customer,
customer, provider, RS, RS-client, internal) relationship of two provider, Route Server, Route Server client) relationship of two
neighboring BGP speakers to enforce appropriate configuration on both neighboring BGP speakers to enforce appropriate configuration on both
sides. Propagated routes are then marked with an iOTC attribute sides. Propagated routes are then marked with an OTC attribute
according to agreed relationship allowing prevention of route leaks. according to the agreed relationship, allowing both prevention and
detection of route leaks.
Requirements Language 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" are to "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
be interpreted as described in RFC 2119 [RFC2119] only when they "OPTIONAL" in this document are to be interpreted as described in
appear in all upper case. They may also appear in lower or mixed BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
case as English words, without normative meaning. capitals, as shown here.
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
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This Internet-Draft will expire on August 19, 2019. This Internet-Draft will expire on January 9, 2020.
Copyright Notice Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Peering Relationships . . . . . . . . . . . . . . . . . . . . 3 2. Peering Relationships . . . . . . . . . . . . . . . . . . . . 3
3. BGP Role . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. BGP Role . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Role capability . . . . . . . . . . . . . . . . . . . . . . . 4 4. Role capability . . . . . . . . . . . . . . . . . . . . . . . 4
5. Role correctness . . . . . . . . . . . . . . . . . . . . . . 5 5. Role correctness . . . . . . . . . . . . . . . . . . . . . . 5
5.1. Strict mode . . . . . . . . . . . . . . . . . . . . . . . 6 5.1. Strict mode . . . . . . . . . . . . . . . . . . . . . . . 5
6. BGP Internal Only To Customer attribute . . . . . . . . . . . 6 6. BGP Only To Customer attribute . . . . . . . . . . . . . . . 6
7. Attribute or Community . . . . . . . . . . . . . . . . . . . 6 7. Enforcement . . . . . . . . . . . . . . . . . . . . . . . . . 6
8. Compatibility with BGPsec . . . . . . . . . . . . . . . . . . 7 8. Additional Considerations . . . . . . . . . . . . . . . . . . 7
9. Additional Considerations . . . . . . . . . . . . . . . . . . 7 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 10. Security Considerations . . . . . . . . . . . . . . . . . . . 8
11. Security Considerations . . . . . . . . . . . . . . . . . . . 8 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 12.1. Normative References . . . . . . . . . . . . . . . . . . 8
13.1. Normative References . . . . . . . . . . . . . . . . . . 8 12.2. Informative References . . . . . . . . . . . . . . . . . 9
13.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
This document specifies a new BGP Capability Code, [RFC5492] Sec 4, BGP route leaks are BGP route(s) which were learned from transit
which two BGP speakers MAY use to ensure that they MUST agree on provider or peer and then announced to another provider or peer. See
their relationship; i.e. customer and provider or peers. Either or [RFC7908]. These are usually the result of misconfigured or absent
both MAY optionally be configured to require that this option be BGP route filtering or lack of coordination between two BGP speakers.
exchanged for the BGP Open to succeed.
Also this document specifies a way to mark routes according to BGP
Roles established in OPEN message and a way to create double-boundary
filters for prevention of route leaks using the new BGP Path
Attribute.
For the purpose of this document, BGP route leaks are when a BGP The mechanism proposed in
route was learned from transit provider or peer and is announced to [I-D.ietf-idr-route-leak-detection-mitigation] uses large-communities
another provider or peer. See[RFC7908]. These are usually the to attempt detection of route leaks. While signaling using
result of misconfigured or absent BGP route filtering or lack of communities is easy to implement, ut relies on operator maintained
coordination between two BGP speakers. policy configuration which is too easily, and too often,
misconfigured. Another problem may occur if the community signal is
stripped, accidentally or maliciously.
[I-D.ietf-idr-route-leak-detection-mitigation] The mechanism proposed This document provides configuration automation using 'BGP roles',
in that draft provides the opportunity to detect route leaks made by which are negotiated using a new BGP Capability Code in OPEN message,
third parties but provides no mechanism to strongly prevent route [RFC5492] Sec 4. Either or both BGP speakers MAY be configured to
leak creation. require that this capability be agreed for the BGP OPEN to succeed.
Also, route tagging which relies on operator maintained policy A new BGP Path Attribute is specified that SHOULD be automatically
configuration is too easily, and too often, misconfigured. configured using BGP roles. This attribute prevents networks from
creating leaks, and detects leaks created by third-parties.
2. Peering Relationships 2. Peering Relationships
Despite uses of words such as "Customer," "Peer." etc. described Despite uses of words such as "Customer," "Peer." etc.; these are not
above are not business relationships, who pays whom, etc. These are business relationships, who pays whom, etc. These are common terms
common terms to represent restrictions on BGP route propagation, to represent restrictions on BGP route propagation, sometimes known
sometimes known as the Gao-Rexford model. as the Gao-Rexford model [cite].
A Provider: MAY send to a customer all available prefixes. A Provider: MAY send to a customer all available prefixes.
A Customer: MAY send to a provider their own prefixes and prefixes A Customer: MAY send to a provider their own prefixes and prefixes
learned from any of their customers. A customer MUST NOT send to learned from any of their customers. A customer MUST NOT send to
a provider prefixes learned from peers, other providers, or RS. a provider prefixes learned from its peers, from other providers,
or from Route Servers.
A Route Server (RS) MAY send to a RS client all available prefixes. A Route Server (RS) MAY send to a RS Client all available prefixes.
A Route Server Client (RS-client) MAY send to an RS its own prefixes A Route Server Client (RS-client) MAY send to an RS its own prefixes
and prefixes learned from its customers. A RS-client MUST NOT and prefixes learned from its customers. A RS-client MUST NOT
send to an RS prefixes learned from peers, providers, or other RS. send to an RS prefixes learned from peers, from its providers, or
from other RS(s).
A Peer: MAY send to a peer its own prefixes and prefixes learned A Peer: MAY send to a peer its own prefixes and prefixes learned
from its customers. A peer MUST NOT send to a peer prefixes from its customers. A peer MUST NOT send to a peer prefixes
learned from other peers, providers, or RS. learned from other peers, from its providers, or from RS(s).
An Internal: MAY send all available prefixes through internal link.
Of course, any BGP speaker may apply policy to reduce what is Of course, any BGP speaker may apply policy to reduce what is
announced, and a recipient may apply policy to reduce the set of announced, and a recipient may apply policy to reduce the set of
routes they accept. But violation of rules marked MUST NOT may routes they accept. Violation of the above rules may result in route
result in route leaks. While these peering relations cover 99% of leaks so MUST not be allowed. Automatic enforment of these rules
possible scenarios, their configuration isn't part of the BGP itself, should significantly reduce configuration mistakes. While these
thus requiring configuration of communities and corresponding egress enforcing the above rules will address most BGP peering scenarios,
prefix filters. The automation of this process may significantly their configuration isn't part of BGP itself; therefore requiring
decrease number of configuration mistakes. configuration of ingress and egress prefix filters is still strongly
advised.
3. BGP Role 3. BGP Role
BGP Role is new configuration option that SHOULD be configured on BGP Role is new configuration option that SHOULD be configured on
each BGP session. It reflects the real-world agreement between two each BGP session. It reflects the real-world agreement between two
BGP speakers about their peering relationship. BGP speakers about their relationship.
Allowed Role values for eBGP sessions are: Allowed Role values for eBGP sessions are:
o Provider - sender is a transit provider to neighbor; o Provider - sender is a transit provider to neighbor;
o Customer - sender is customer of neighbor; o Customer - sender is transit customer of neighbor;
o RS - sender is route server at internet exchange point (IX) o RS - sender is a Route Server, usually at internet exchange point
(IX)
o RS-client - sender is client of RS at internet exchange point (IX) o RS-Client - sender is client of RS
o Peer - sender and neighbor are peers; o Peer - sender and neighbor are peers;
o Internal - sender and neighbor are part of the same organization.
For iBGP sessions, only the Internal role MAY be configured.
Since BGP Role reflects the relationship between two BGP speakers, it Since BGP Role reflects the relationship between two BGP speakers, it
could also be used for more than route leak mitigation. could also be used for more than route leak mitigation.
4. Role capability 4. Role capability
The TLV (type, length, value) of the BGP Role capability are: The TLV (type, length, value) of the BGP Role capability are:
o Type - <TBD1>; o Type - <TBD1>;
o Length - 1 (octet); o Length - 1 (octet);
o Value - integer corresponding to speaker' BGP Role. o Value - integer corresponding to speaker' BGP Role.
+-------+---------------------+ +-------+---------------------+
| Value | Role name | | Value | Role name |
+-------+---------------------+ +-------+---------------------+
| 0 | Sender is Internal | | 0 | Sender is Provider |
| 1 | Sender is Provider | | 1 | Sender is RS |
| 2 | Sender is RS | | 2 | Sender is RS-Client |
| 3 | Sender is RS-Client | | 3 | Sender is Customer |
| 4 | Sender is Customer | | 4 | Sender is Peer |
| 5 | Sender is Peer |
+-------+---------------------+ +-------+---------------------+
Table 1: Predefined BGP Role Values Table 1: Predefined BGP Role Values
5. Role correctness 5. Role correctness
Section 3 described how BGP Role is a reflection of the relationship Section 3 described how BGP Role encodes the relationship between two
between two BGP speakers. But the mere presence of BGP Role doesn't BGP speakers. But the mere presence of BGP Role doesn't
automatically guarantee role agreement between two BGP peers. automatically guarantee role agreement between two BGP peers.
To enforce correctness, the BGP Role check is used with a set of To enforce correctness, the BGP Role check is used with a set of
constrains on how speakers' BGP Roles MUST correspond. Of course, constrains on how speakers' BGP Roles MUST correspond. Of course,
each speaker MUST announce and accept the BGP Role capability in the each speaker MUST announce and accept the BGP Role capability in the
BGP OPEN message exchange. BGP OPEN message exchange.
If a speaker receives a BGP Role capability, it MUST check the value If a speaker receives a BGP Role capability, it MUST check the value
of the received capability with its own BGP Role (if it is set). The of the received capability with its own BGP Role (if it is set). The
allowed pairings are (first a sender's Role, second the receiver's allowed pairings are (first a sender's Role, second the receiver's
Role): Role):
+-------------+---------------+ +-------------+---------------+
| Sender Role | Receiver Role | | Sender Role | Receiver Role |
+-------------+---------------+ +-------------+---------------+
| Internal | Internal |
| Provider | Customer | | Provider | Customer |
| Customer | Provider | | Customer | Provider |
| RS | RS-Client | | RS | RS-Client |
| RS-Client | RS | | RS-Client | RS |
| Peer | Peer | | Peer | Peer |
+-------------+---------------+ +-------------+---------------+
Table 2: Allowed Role Capabilities Table 2: Allowed Role Capabilities
In case of any other pairs of roles, a speaker MUST send a Role If the Role pair is not in the above table, a speaker MUST send a
Mismatch Notification (code 2, sub-code <TBD2>). Role Mismatch Notification (code 2, sub-code <TBD2>).
5.1. Strict mode 5.1. Strict mode
A new BGP configuration option "strict mode" is defined with values A new BGP configuration option "strict mode" is defined with values
of true or false. If set to true, then the speaker MUST refuse to of true or false. If set to true, then the speaker MUST refuse to
establish a BGP session with a neighbor which does not announce the establish a BGP session with a neighbor which does not announce the
BGP Role capability in their OPEN message. If a speaker rejects a BGP Role capability in the OPEN message. If a speaker rejects a
connection, it MUST send a Connection Rejected Notification [RFC4486] connection, it MUST send a Connection Rejected Notification [RFC4486]
(Notification with error code 6, subcode 5). By default, strict mode (Notification with error code 6, subcode 5). By default, strict mode
SHOULD be set to false for backward compatibility with BGP speakers SHOULD be set to false for backward compatibility with BGP speakers
that do not yet support this mechanism. that do not yet support this mechanism.
6. BGP Internal Only To Customer attribute 6. BGP Only To Customer attribute
The Internal Only To Customer (iOTC) attribute is a new optional, The Only To Customer (OTC) BGP Attribute is a new optional,
non-transitive BGP Path attribute with the Type Code <TBD3>. This transitive BGP Path attribute with the Type Code <TBD3>.
attribute has zero length as it is used only as a flag.
There are four rules of iOTC attribute usage: This four byte attribute MUST apply the following policy:
1. The iOTC attribute MUST be added to all incoming routes if the 1. If a route with OTC attribute is received from Customer or RS-
receiver's Role is Customer, Peer, or RS-client; client - it's a route leak and MUST be rejected.
2. Routes with the iOTC attribute set MUST NOT be announced by a 2. If a route with OTC attribute is received from Peer and its value
sender whose Role is Customer, Peer, or RS-client; isn't equal to the neighbor's ASN - it's a route leak and MUST be
rejected.
3. A sender MUST NOT include iOTC in UPDATE messages advertised to 3. If a route is received from a Provider, Peer or RS and the OTC
eBGP neighbor if its Role isn't Internal. attribute has not been set it MUST be added with value equal to
AS number of the neighbor (sender).
4. If iOTC is contained in an UPDATE message from eBGP speaker and The egress policy MUST be:
receiver's Role isn't Internal then this attribute MUST be
removed.
These rules provide mechanism to strongly prevent route leak creation 1. A route with the OTC attribute set MUST NOT be sent to providers,
by an AS. peers, or RS(s).
7. Attribute or Community 2. If route is sent to customer or peer and the OTC attribute is not
set it MUST be added with value equal to AS number of the sender.
Having the relationship hard set by agreement between the two peers Once the OTC attribute has been set, it MUST be preserved unchanged.
in BGP OPEN is critical; the routers enforce the relationship
irrespective of operator policy configuration errors.
Similarly, it is critical that the application of that relationship 7. Enforcement
on prefix propagation using iOTC is enforced by the router(s), and
minimally exposed to user mis-configuration. There is a question
whether the iOTC marking should be an attribute or a well-known
community.
There is a long and sordid history of mis-configurations inserting Having the relationship unequivocally agreed between the two peers in
incorrect communities, deleting communities, ignoring well-known BGP OPEN is critical; the BGP implementations enforce the
community markings etc. In this mechanism's case, an operator could, relationship irrespective of operator policy configuration errors.
for example, accidentally strip the well-known community on receipt.
Similarly, the application of that relationship on prefix propagation
using OTC MUST BE enforced by the BGP implementations, and not
exposed to user mis-configuration.
As opposed to communities, BGP attributes may not be generally As opposed to communities, BGP attributes may not be generally
modified or filtered by the operator. The router(s) enforce them. modified or filtered by the operator. The router(s) enforce them.
This is the desired property for the iOTC marking. Hence, this This is the desired property for the OTC marking. Hence, this
document specifies iOTC as an attribute. document specifies OTC as an attribute.
8. Compatibility with BGPsec
As the iOTC attribute is non-transitive, it is not seen by or signed
by BGPsec [RFC8205].
9. Additional Considerations 8. Additional Considerations
As the BGP Role reflects the peering relationship between neighbors, As the BGP Role reflects the peering relationship between neighbors,
it can also have other uses. As an example, BGP Role might affect it might have other uses. For example, BGP Role might affect route
route priority, or be used to distinguish borders of a network if a priority, or be used to distinguish borders of a network if a network
network consists of multiple ASs. consists of multiple ASs. Though such uses may be worthwhile, they
are not the goal of this document. Note that such uses would require
Though such uses may be worthwhile, they are not the goal of this local policy control.
document. Note that such uses would require local policy control.
As BGP role configuration results in automatic creation of inbound/ As BGP role configuration results in automatic creation of inbound/
outbound filters, existence of roles should be treated as existence outbound filters, existence of roles should be treated as existence
of Import and Export policy. [RFC8212] of Import and Export policy. [RFC8212]
This document doesn't provide any security measures to check There are peering relationships which are 'complex'; e.g. when both
correctness of iOTC usage if role isn't configured. parties are intentionally sending prefixes received from each other
to their peers and/or upstreams. If multiple BGP peerings can
segregate the 'complex' parts of the relationship, the complex
peering roles can be segregated into different BGP sessions, and
normal BGP Roles MUST be used on the non-complex sessions. No Roles
SHOULD be configured on 'complex' BGP sessions, and OTC MUST be set
by configuration on a per-prefix basis. There can be no measures to
check correctness of OTC use if Role is not configured.
10. IANA Considerations 9. IANA Considerations
This document defines a new Capability Codes option [to be removed This document defines a new Capability Codes option [to be removed
upon publication: http://www.iana.org/assignments/capability-codes/ upon publication: http://www.iana.org/assignments/capability-codes/
capability-codes.xhtml] [RFC5492], named "BGP Role", assigned value capability-codes.xhtml] [RFC5492], named "BGP Role", assigned value
<TBD1> . The length of this capability is 1. <TBD1> . The length of this capability is 1.
The BGP Role capability includes a Value field, for which IANA is The BGP Role capability includes a Value field, for which IANA is
requested to create and maintain a new sub-registry called "BGP Role requested to create and maintain a new sub-registry called "BGP Role
Value". Assignments consist of Value and corresponding Role name. Value". Assignments consist of Value and corresponding Role name.
Initially this registry is to be populated with the data in Table 1. Initially this registry is to be populated with the data in Table 1.
Future assignments may be made by a standard action Future assignments may be made by a standard action
procedure[RFC5226]. procedure[RFC5226].
This document defines new subcode, "Role Mismatch", assigned value This document defines new subcode, "Role Mismatch", assigned value
<TBD2> in the OPEN Message Error subcodes registry [to be removed <TBD2> in the OPEN Message Error subcodes registry [to be removed
upon publication: http://www.iana.org/assignments/bgp-parameters/bgp- upon publication: http://www.iana.org/assignments/bgp-parameters/bgp-
parameters.xhtml#bgp-parameters-6] [RFC4271]. parameters.xhtml#bgp-parameters-6] [RFC4271].
This document defines a new optional, non-transitive BGP Path This document defines a new optional, transitive BGP Path Attributes
Attributes option, named "Internal Only To Customer", assigned value option, named "Only To Customer", assigned value <TBD3> [To be
<TBD3> [To be removed upon publication: removed upon publication: http://www.iana.org/assignments/bgp-
http://www.iana.org/assignments/bgp-parameters/bgp- parameters/bgp-parameters.xhtml#bgp-parameters-2] [RFC4271]. The
parameters.xhtml#bgp-parameters-2] [RFC4271]. The length of this length of this attribute is 0.
attribute is 0.
11. Security Considerations 10. Security Considerations
This document proposes a mechanism for prevention of route leaks that This document proposes a mechanism for prevention of route leaks that
are the result of BGP policy mis-configuration. are the result of BGP policy mis-configuration.
Deliberate sending of a known conflicting BGP Role could be used to Deliberate sending of a known conflicting BGP Role could be used to
sabotage a BGP connection. This is easily detectable. sabotage a BGP connection. This is easily detectable.
BGP Role is disclosed only to an immediate BGP neighbor, so it will A misconfiguration in OTC setup may affect prefix propagation. But
not itself reveal any sensitive information to third parties. the automation that is provided by BGP roles should make such
misconfiguration unlikely.
12. Acknowledgments 11. Acknowledgments
The authors wish to thank Douglas Montgomery, Brian Dickson, Andrei The authors wish to thank Douglas Montgomery, Brian Dickson, Andrei
Robachevsky and Daniel Ginsburg for their contributions to a variant Robachevsky, and Daniel Ginsburg for their contributions to a variant
of this work. of this work.
13. References 12. References
13.1. Normative References 12.1. Normative References
[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>.
[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>.
[RFC4486] Chen, E. and V. Gillet, "Subcodes for BGP Cease [RFC4486] Chen, E. and V. Gillet, "Subcodes for BGP Cease
Notification Message", RFC 4486, DOI 10.17487/RFC4486, Notification Message", RFC 4486, DOI 10.17487/RFC4486,
April 2006, <https://www.rfc-editor.org/info/rfc4486>. April 2006, <https://www.rfc-editor.org/info/rfc4486>.
[RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement [RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement
with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February
2009, <https://www.rfc-editor.org/info/rfc5492>. 2009, <https://www.rfc-editor.org/info/rfc5492>.
13.2. Informative References [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>.
12.2. Informative References
[I-D.ietf-idr-route-leak-detection-mitigation] [I-D.ietf-idr-route-leak-detection-mitigation]
Sriram, K. and A. Azimov, "Methods for Detection and Sriram, K. and A. Azimov, "Methods for Detection and
Mitigation of BGP Route Leaks", draft-ietf-idr-route-leak- Mitigation of BGP Route Leaks", draft-ietf-idr-route-leak-
detection-mitigation-10 (work in progress), October 2018. detection-mitigation-10 (work in progress), October 2018.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 5226, IANA Considerations Section in RFCs", RFC 5226,
DOI 10.17487/RFC5226, May 2008, DOI 10.17487/RFC5226, May 2008,
<https://www.rfc-editor.org/info/rfc5226>. <https://www.rfc-editor.org/info/rfc5226>.
[RFC7908] Sriram, K., Montgomery, D., McPherson, D., Osterweil, E., [RFC7908] Sriram, K., Montgomery, D., McPherson, D., Osterweil, E.,
and B. Dickson, "Problem Definition and Classification of and B. Dickson, "Problem Definition and Classification of
BGP Route Leaks", RFC 7908, DOI 10.17487/RFC7908, June BGP Route Leaks", RFC 7908, DOI 10.17487/RFC7908, June
2016, <https://www.rfc-editor.org/info/rfc7908>. 2016, <https://www.rfc-editor.org/info/rfc7908>.
[RFC8205] Lepinski, M., Ed. and K. Sriram, Ed., "BGPsec Protocol
Specification", RFC 8205, DOI 10.17487/RFC8205, September
2017, <https://www.rfc-editor.org/info/rfc8205>.
[RFC8212] Mauch, J., Snijders, J., and G. Hankins, "Default External [RFC8212] Mauch, J., Snijders, J., and G. Hankins, "Default External
BGP (EBGP) Route Propagation Behavior without Policies", BGP (EBGP) Route Propagation Behavior without Policies",
RFC 8212, DOI 10.17487/RFC8212, July 2017, RFC 8212, DOI 10.17487/RFC8212, July 2017,
<https://www.rfc-editor.org/info/rfc8212>. <https://www.rfc-editor.org/info/rfc8212>.
Authors' Addresses Authors' Addresses
Alexander Azimov Alexander Azimov
Qrator Labs Qrator Labs
Email: a.e.azimov@gmail.com Email: a.e.azimov@gmail.com
Eugene Bogomazov Eugene Bogomazov
Qrator Labs Qrator Labs
Email: eb@qrator.net Email: eb@qrator.net
Randy Bush Randy Bush
Internet Initiative Japan Internet Initiative Japan & Arrcus
Email: randy@psg.com Email: randy@psg.com
Keyur Patel Keyur Patel
Arrcus, Inc. Arrcus, Inc.
Email: keyur@arrcus.com Email: keyur@arrcus.com
Kotikalapudi Sriram Kotikalapudi Sriram
US NIST US NIST
Email: ksriram@nist.gov Email: ksriram@nist.gov
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