Internet DRAFT - draft-sriram-idr-route-leak-detection-mitigation
draft-sriram-idr-route-leak-detection-mitigation
IDR and SIDR K. Sriram
Internet-Draft D. Montgomery
Intended status: Standards Track US NIST
Expires: January 6, 2016 B. Dickson
Twitter, Inc.
July 5, 2015
Methods for Detection and Mitigation of BGP Route Leaks
draft-sriram-idr-route-leak-detection-mitigation-01
Abstract
In [I-D.ietf-grow-route-leak-problem-definition], the authors have
provided a definition of the route leak problem, and also enumerated
several types of route leaks. In this document, we first examine
which of those route-leak types are detected and mitigated by the
existing origin validation (OV) [RFC 6811] and BGPSEC path validation
[I-D.ietf-sidr-bgpsec-protocol]. Where the current OV and BGPSEC
protocols don't offer a solution, this document suggests an
enhancement that would extend the route-leak detection and mitigation
capability of BGPSEC. The solution can be implemented in BGP without
necessarily tying it to BGPSEC. Incorporating the solution in BGPSEC
is one way of implementing it in a secure way. We do not claim to
have provided a solution for all possible types of route leaks, but
the solution covers several, especially considering some significant
route-leak attacks or occurrences that have been observed in recent
years. The document also includes a stopgap method for detection and
mitigation of route leaks for the phase when BGPSEC (path validation)
is not yet deployed but only origin validation is deployed.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 6, 2016.
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Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Related Prior Work . . . . . . . . . . . . . . . . . . . . . 3
3. Mechanisms for Detection and Mitigation of Route Leaks . . . 4
3.1. Route Leak Protection (RLP) Field Encoding by Sending
Router . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Recommended Actions at a Receiving Router for Detection
of Route Leaks . . . . . . . . . . . . . . . . . . . . . 8
3.2.1. Recommended Actions at a Receiving Router when the
Sender is a Customer . . . . . . . . . . . . . . . . 8
3.2.2. Recommended Actions at a Receiving Router when the
Sender is a Peer . . . . . . . . . . . . . . . . . . 9
3.3. Possible Actions at a Receiving Router for Mitigation . . 10
4. Stopgap Solution when Only Origin Validation is Deployed . . 10
5. Design Rationale and Discussion . . . . . . . . . . . . . . . 11
5.1. Is route-leak solution without BGPSEC a serious attack
vector? . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.2. Comparison with other methods, routing security BCP . . . 12
6. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
In [I-D.ietf-grow-route-leak-problem-definition], the authors have
provided a definition of the route leak problem, and also enumerated
several types of route leaks. In this document, we first examine
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which of those route-leak types are detected and mitigated by the
existing Origin Validation (OV) [RFC6811] and BGPSEC path validation
[I-D.ietf-sidr-bgpsec-protocol]. For the rest of this document, we
use the term BGPSEC as synonymous with path validation. The BGPSEC
protocol provides cryptographic protection for some aspects of BGP
update messages. OV and BGPSEC together offer mechanisms to protect
against mis-originations and hijacks of IP prefixes as well as man-
in-the-middle (MITM) AS path modifications. Route leaks (see
[I-D.ietf-grow-route-leak-problem-definition] and references cited at
the back) are another type of vulnerability in the global BGP routing
system against which OV and BGPSEC so far offer only partial
protection.
For the types of route leaks enumerated in
[I-D.ietf-grow-route-leak-problem-definition], where the current OV
and BGPSEC protocols don't offer a solution, this document suggests
an enhancement that would extend the detection and mitigation
capability of BGPSEC. The solution can be implemented in BGP without
necessarily tying it to BGPSEC. Incorporating the solution in BGPSEC
is one way of implementing it in a secure way. We do not claim to
provide a solution for all possible types of route leaks, but the
solution covers several relevant types, especially considering some
significant route-leak occurrences that have been observed frequently
in recent years. The document also includes (in Section 4) a stopgap
method for detection and mitigation of route leaks for the phase when
BGPSEC (path validation) is not yet deployed but only origin
validation is deployed.
2. Related Prior Work
The basic idea and mechanism embodied in the proposed solution is
based on setting an attribute in BGP route announcement to manage the
transmission/receipt of the announcement based on the type of
neighbor (e.g. customer, provider, etc.). Documented prior work
related to said basic idea and mechanism dates back to at least the
1980's. Some examples of prior work are: (1) Information flow rules
described in [proceedings-sixth-ietf] (see pp. 195-196); (2) Link
Type described in [RFC1105-obsolete] (see pp. 4-5); (3) Hierarchical
Recording described in [draft-kunzinger-idrp-ISO10747-01] (see
Section 6.3.1.12). The problem of route leaks and possible solution
mechanisms based on encoding peering-link type information (e.g. p2c,
c2p, p2p, etc.) in BGPSEC updates and protecting the same under
BGPSEC path signatures have been discussed in IETF SIDR WG at least
since 2011. Dickson developed the initial Internet draft of these
mechanisms in a BGPSEC context; see
[draft-dickson-sidr-route-leak-solns]. The draft expired in 2012.
[draft-dickson-sidr-route-leak-solns] defined neighbor relationships
on a per link basis, but in the current draft the relationship in
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encoded per prefix, as prefixes with different business models are
often sent over the same link. Also
[draft-dickson-sidr-route-leak-solns] proposed a second signature
block for the link type encoding, separate from the path signature
block in BGPSEC. By contrast, in the current draft when BGPSEC-based
solution is considered, cryptographic protection is provided for
Route Leak Protection (RLP) encoding using the same signature block
as that for path signatures (see Section 3.1).
3. Mechanisms for Detection and Mitigation of Route Leaks
Referring to the enumeration of route leaks discussed in
[I-D.ietf-grow-route-leak-problem-definition], Table 1 summarizes the
route-leak detection capability offered by OV and BGPSEC for
different types of route leaks. (Note: Prefix filtering is not
considered here in this table. Please see Section 4.)
A detailed explanation of the contents of Table 1 is as follows. It
is readily observed that route leaks of Types 1, 5, 6, and 7 are not
detected by OV or even by BGPSEC. Type 2 route leak involves
changing a prefix to a subprefix (i.e. more specific); such a
modified update will fail BGPSEC checks. Clearly, Type 3 route leak
involves mis-origination or hijacking, and hence can be detected by
OV. In the case of Type 3 route leak, there would be no existing
ROAs to validate a re-originated prefix or subprefix, but instead a
covering ROA would normally exist with the legitimate AS, and hence
the update will be considered Invalid by OV.
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+---------------------------------+---------------------------------+
| Type of Route Leak | Detection Coverage and Comments |
+---------------------------------+---------------------------------+
| Type 1: U-Turn with Full Prefix | Neither OV nor BGPSEC (in its |
| | current form) detects Type 1. |
| ------------------------------- | ------------------------------- |
| Type 2: U-Turn with More | In OV, the ROA maxLength may |
| Specific Prefix | offer detection of Type 2 in |
| | some cases; BGPSEC (in its |
| | current form) always detects |
| | Type 2. |
| ------------------------------- | ------------------------------- |
| Type 3: Prefix Mis-Origination | OV by itself detects Type 3; |
| with Data Path to Legitimate | BGPSEC does not detect Type 3. |
| Origin | |
| ------------------------------- | ------------------------------- |
| Type 4: Leak of Internal | For internal prefixes never |
| Prefixes and Accidental | meant to be seen (i.e. routed) |
| Deaggregation | on the Internet, OV helps |
| | detect their leak; they might |
| | either have no covering ROA or |
| | have an AS0-ROA to always |
| | filter them. In the case of |
| | accidental deaggregation, OV |
| | may offer some detection due to |
| | ROA maxLength. BGPSEC does not |
| | catch Type 4. |
| ------------------------------- | ------------------------------- |
| Type 5: Lateral ISP-ISP-ISP | Neither OV nor BGPSEC (in its |
| Leak | current form) detects Type 5. |
| ------------------------------- | ------------------------------- |
| Type 6: Leak of Provider | Neither OV nor BGPSEC (in its |
| Prefixes to Peer | current form) detects Type 6. |
| ------------------------------- | ------------------------------- |
| Type 7: Leak of Peer Prefixes | Neither OV nor BGPSEC (in its |
| to Provider | current form) detects Type 7. |
+---------------------------------+---------------------------------+
Table 1: Examination of Route-Leak Detection Capability of Origin
Validation and Current BGPSEC Path Validation
In the case of Type 4 leaks involving internal prefixes that are not
meant to be routed in the Internet, they are likely to be detected by
OV. That is because such prefixes might either have no covering ROA
or have an AS0-ROA to always filter them. In the case of Type 4
leaks that are due to accidental deaggregation, they may be detected
due to violation of ROA maxLength. BGPSEC does not catch Type 4.
However, route leaks of Type 4 are least problematic due to the
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following reasons. In the case of accidental deaggregation, the
offending AS is itself the legitimate destination of the leaked more-
specific prefixes. Hence, in most cases of this type, the data
traffic is neither misrouted not denied service. Also, leaked
announcements of Type 4 are short-lived and typically withdrawn
quickly following the announcements. Further, the MaxPrefix limit
may kick-in in some receiving routers and that helps limit the
propagation of sometimes large number of leaked routes of Type 4.
Realistically, BGPSEC may take a much longer time being deployed than
OV. Hence solution proposals for route leaks should consider both
scenarios: (A) OV only (without BGPSEC) and (B) OV plus BGPSEC.
Assuming an initial scenario A, and based on the above discussion and
Table 1, it is evident that in our proposed solution method, we need
to focus primarily on route leaks of Types 1, 2, 5, 6, and 7. In
Section 3.1 and Section 3.2, we describe a simple addition to BGP
that facilitates detection of route leaks of Types 1, 2, 5, 6, and 7.
The simple addition involves a Route Leak Protection (RLP) field,
which is carried in an optional transitive path attribute in BGP.
When BGPSEC is deployed, the RLP field will be accommodated in the
existing Flags field (see [I-D.ietf-sidr-bgpsec-protocol]) which is
cryptographically protected under path signatures.
3.1. Route Leak Protection (RLP) Field Encoding by Sending Router
The key principle is that, in the event of a route leak, a receiving
router in a provider AS (e.g. referring to Figure 1, ISP2 (AS2)
router) should be able to detect from the prefix-update that its
customer AS (e.g. AS3 in Figure 1) SHOULD NOT have forwarded the
update (towards the provider AS). This means that at least one of
the ASes in the AS path of the update has indicated that it sent the
update to its customer or peer AS, but forbade any subsequent 'Up'
forwarding (i.e. from a customer AS to its provider AS). For this
purpose, a Route Leak Protection (RLP) field to be set by a sending
router is proposed to be used for each AS hop.
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/\ /\
\ route-leak(P)/
\ propagated /
\ /
+------------+ peer +------------+
______| ISP1 (AS1) |----------->| ISP2 (AS2)|---------->
/ ------------+ prefix(P) +------------+ route-leak(P)
| prefix | \ update /\ \ propagated
\ (P) / \ / \
------- prefix(P) \ / \
update \ / \
\ /route-leak(P) \/
\/ /
+---------------+
| customer(AS3) |
+---------------+
Figure 1: Illustration of the basic notion of a route leak.
For the purpose of route leak detection and mitigation proposed in
this document, the RLP field value SHOULD be set to one of two values
as follows:
o 00: This is the default value (i.e. "nothing specified"),
o 01: This is the 'Do not Propagate Up' indication; sender
indicating that the prefix-update SHOULD NOT be forwarded 'Up'
towards a provider AS.
There are two different scenarios when a sending AS SHOULD set the
'01' indication in a prefix-update: (1) when sending the prefix-
update to a customer AS, and (2) to let a peer AS know not to forward
the prefix-update 'Up' towards a provide AS. In essence, in both
scenarios, the intent of '01' indication is that any receiving AS
along the subsequent AS path SHOULD NOT forward the prefix-update
'Up' towards its (receiving AS's) provider AS.
One may argue for additional RLP indications: for example, '10' to
specify 'Propagate to Customers Only', and possibly '11' to signal
'Do Not Propagate' (i.e. NO_EXPORT). But in the interest of keeping
the methodology simple, the choice of two RLP field values as defined
above (00 - default, and 01 - 'Do not Propagate Up') is all that is
needed. This two-state specification in the RLP field can be shown
to work for detection and mitigation of route leaks of Types 1, 2, 5,
6, and 7, which are the focus here (see Section 3.2 and Section 3.3).
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The proposed RLP encoding SHOULD be carried in BGP-4 [RFC4271]
updates in an optional transitive path attribute. In BGPSEC enabled
routers, the RLP encoding SHOULD be accommodated in the existing
Flags field in BGPSEC updates. The Flags field is part of the
Secure_Path Segment in BPGSEC updates
[I-D.ietf-sidr-bgpsec-protocol]. It is one octet long, and one Flags
field is available for each AS hop, and currently only the first bit
is used in BGPSEC. So there are 7 bits that are currently unused in
the Flags field. Two (or more if needed) of these bits can be
designated for the RLP field. Since the BGPSEC protocol
specification requires a sending AS to include the Flags field in the
data that are signed over, the RLP field for each hop (assuming it
would be part of the Flags field) will be protected under the sending
AS's signature.
3.2. Recommended Actions at a Receiving Router for Detection of Route
Leaks
The recommended receiver actions differ slightly depending on whether
the update is received from a customer or a peer. When detecting
route leaks of Type 1, 2, and 7, the receiving router is dealing with
a customer as the sender. When detecting route leaks of Type 5 and
6, the receiving router is dealing with a peer as the sender.
3.2.1. Recommended Actions at a Receiving Router when the Sender is a
Customer
We provide here an example set of receiver actions that work to
detect and mitigate route leaks of Types 1, 2, and 7. This example
algorithm serves as a proof of concept. However, other receiver
algorithms or procedures can be designed (based on the same sender
specification as in Section 3.1) and may perform with greater
efficacy, and are by no means excluded.
A recommended receiver algorithm for detecting a route leak is as
follows:
A receiving router SHOULD mark an update as a Route-Leak if ALL of
the following conditions hold true:
1. The update is received from a customer AS.
2. It is Valid in accordance with the Origin Validation (OV) and
BGPSEC protocols. (Note: BGPSEC validation is not applicable if
update is not signed).
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3. The update has the RLP field set to '01' (i.e. 'Do not Propagate
Up') indication for one or more hops (excluding the most recent)
in the AS path.
The reason for stating "excluding the most recent" in the above
algorithm is as follows. The provider AS already knows that the most
recent hop in the update is from its customer AS to itself, and it
does not need to rely on the RLP field value set by the customer for
detection of route leaks.
A receiving router expects the RLP field value for any hop in the AS
path to be either 00 or 01. However, if a different value (say, 10
or 11) is found in the RLP field, then an error condition will get
flagged, and any further action is TBD.
3.2.2. Recommended Actions at a Receiving Router when the Sender is a
Peer
The sender and receiver actions described in Section 3.1 and
Section 3.2.1 clearly help detect and mitigate route leaks of Types
1, 2, and 7. With a slightly modified interpretation of the RLP
encoding on the receiver side, they can be extended to detect lateral
ISP-ISP-ISP route leaks (Type 5) as well as leaks of provider
prefixes to peer (Type 6). (Note: RLP encoding procedure by sending
routers remains the same as described in Section 3.1.)
A recommended receiver algorithm for an ISP to detect a route leak of
either Type 5 or Type 6 is as follows:
A receiving BGPSEC router SHOULD mark an update as a Route-Leak if
ALL of the following conditions hold true:
1. The update is received from a lateral ISP peer.
2. It is Valid in accordance with the Origin Validation (OV) and
BGPSEC protocols. (Note: BGPSEC validation is not applicable if
update is not signed).
3. The update has the RLP field set to '01' indication for one or
more hops (excluding the most recent) in the AS path.
In the above algorithm, the receiving AS interprets the '01'
indication slightly strongly (i.e. stronger than in Section 3.2.1) to
mean "the update SHOULD NOT have been propagated laterally to a peer
ISP like me either". The rationale here is based on the fact that
settlement-free ISP peers accept only customer prefix-routes from
each other. The receiving AS applies the logic that if a preceding
AS (excluding the most recent) set '01' indication, it means that the
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update was sent to a peer or a customer by the (preceding) AS, and
the update should not be traversing a lateral peer-to-peer link
subsequently.
3.3. Possible Actions at a Receiving Router for Mitigation
After applying the above detection algorithm, a receiving router may
use any policy-based algorithm of its own choosing to mitigate any
detected route leaks. An example receiver algorithm for mitigating a
route leak is as follows:
o If an update from a customer AS is marked as a Route-Leak, then
the receiving router SHOULD prefer a Valid signed update from a
peer or an upstream provider over the customer's update.
A basic principle here is that the presence of '01' value in the RLP
field corresponding to one or more AS hops in the AS path of an
update coming from a customer AS informs a receiving router in a
provider AS that a route leak is likely occurring. The provider AS
then overrides the "prefer customer route" policy, and instead
prefers a route learned from a peer or another upstream provider over
the customer's route.
4. Stopgap Solution when Only Origin Validation is Deployed
During a phase when BGPSEC path validation has not yet been deployed
but only origin validation has been deployed, it would be good have a
stopgap solution for route leaks. The stopgap solution can be in the
form of construction of a prefix filter list from ROAs. A suggested
procedure for constructing such a list comprises of the following
steps:
o ISP makes a list of all the ASes (Cust_AS_List) that are in its
customer cone (ISP's own AS is also included in the list). (Some
of the ASes in Cust_AS_List may be multi-homed to another ISP and
that is OK.)
o ISP downloads from the RPKI repositories a complete list
(Cust_ROA_List) of valid ROAs that contain any of the ASes in
Cust_AS_List.
o ISP creates a list of all the prefixes (Cust_Prfx_List) that are
contained in any of the ROAs in Cust_ROA_List.
o Cust_Prfx_List is the allowed list of prefixes that is permitted
by the ISP's AS, and will be forwarded by the ISP to upstream
ISPs, customers, and peers.
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o Any prefix not in Cust_Prfx_List but announced by any of the ISP's
customers is marked as a potential route leak. Then the ISP's
router SHOULD prefer a Valid (i.e. valid according to origin
validation) and 'not marked' update from a peer or an upstream
provider over the customer's marked update for that prefix.
Special considerations with regard to the above procedure may be
needed for DDoS mitigation service providers. They typically
originate or announce a DDoS victim's prefix to their own ISP on a
short notice during a DDoS emergency. Some provisions would need to
be made for such cases, and they can be determined with the help of
inputs from DDoS mitigation service providers.
For developing a list of all the ASes (Cust_AS_List) that are in the
customer cone of an ISP, the AS path based Outbound Route Filter
(ORF) technique [draft-ietf-idr-aspath-orf] can be helpful (see
discussion in Section 5.2).
5. Design Rationale and Discussion
In this section, we will try to provide design justifications for the
methodology specified in Section 3, and also answer some anticipated
questions.
5.1. Is route-leak solution without BGPSEC a serious attack vector?
It has been asked if a route-leak solution without BGPSEC, i.e. when
RLP bits are not protected, can turn into a serious new attack
vector. That answer seems to be: not really! Even the NLRI and
AS_PATH in BGP updates are attack vectors, and RPKI/OV/BGPSEC seek to
fix that. Consider the following. Say, if 99% of route leaks are
accidental and 1% are malicious, and if route-leak solution without
BGPSEC eliminates the 99%, then perhaps it is worth it (step in the
right direction). When BGPSEC comes into deployment, the route leak
protection (RLP) bits can be mapped into BGPSEC (using the Flags
field) and then necessary security will be in place as well (within
each BGPSEC island as and when they emerge).
Further, let us consider the worst-case damage that can be caused by
maliciously manipulating the RLP bits in an implementation without
BGPSEC. An AS that wants to intentionally leak a route would alter
the RLP encodings for the preceding hops from '01' (i.e. 'Do not
Propagate Up') to '00' (default) wherever applicable. It is true
that in that case a receiving router would not be able to detect the
leak for the specific prefix-route by the RLP mechanism described
here. However, the receiving router may still detect and mitigate it
in some cases by applying other means such as prefix filters
[RFC7454] and AS path filters [draft-ietf-idr-aspath-orf]. If some
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malicious leaks go undetected (for RLP without BGPSEC) that is
possibly a small price to pay for the ability to detect the bulk of
route leaks that are accidental.
5.2. Comparison with other methods, routing security BCP
It is reasonable to ask if techniques considered in BCPs such
as[RFC7454] (BGP Operations and Security) and [NIST-800-54] may be
adequate to address route leaks. The prefix filtering
recommendations in the BCPs may be complementary but not adequate.
The difficulty is in ISPs' ability to construct prefix filters that
represent their customer cones (CC) accurately, especially when there
are many levels in the hierarchy within the CC. In the RLP-encoding
based solution described here, AS operators signal for each prefix-
route propagated, if it SHOULD NOT be subsequently propagated to a
provider/peer.
AS path based Outbound Route Filter (ORF) described in
[draft-ietf-idr-aspath-orf] is also an interesting complementary
technique. It can be used as an automated collaborative messaging
system (implemented in BGP) for ISPs to try to develop a complete
view of the ASes and AS paths in their CCs. Once an ISP has that
view, then AS path filters can be possibly used to detect route
leaks. One limitation of this technique is that it cannot duly take
into account the fact that prefixes with different business models
are often sent over the same link between ASes. Also, the success of
it depends on ASes at all levels of the hierarchy in a CC participate
and provide accurate information (in the ORF messages) about the AS
paths they expect to have in their BGP updates to their provider
ISP(s).
6. Summary
It should be emphasized once again that the proposed route-leak
detection method using the RLP encoding is not intended to cover all
forms of route leaks. However, we feel that the solution covers
several important types of route leaks, especially considering some
significant route-leak attacks or occurrences that have been
frequently observed in recent years. The solution can be implemented
in BGP without necessarily tying it to BGPSEC. The proposed solution
without BGPSEC can detect and mitigate accidental route leaks, and
the same with BGPSEC can detect and mitigate malicious route leaks as
well. Carrying the proposed RLP encoding in an optional transitive
path attribute in BGP is proposed, but in order to prevent abuse, the
RLP encoding would require cryptographic protection. Incorporating
the RLP encoding in the BGPSEC Flags field is one way of implementing
it securely using an already existing protection mechanism provided
in BGPSEC path signatures.
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7. Security Considerations
The proposed Route Leak Protection (RLP) field requires cryptographic
protection in order to prevent malicious route leaks. Since it is
proposed that the RLP field be included in the Flags field in the
Secure_Path Segment in BPGSEC updates, the cryptographic security
mechanisms in BGPSEC are expected to also apply to the RLP field.
The reader is therefore directed to the security considerations
provided in [I-D.ietf-sidr-bgpsec-protocol].
8. IANA Considerations
No updates to the registries are suggested by this document.
9. Acknowledgements
The authors wish to thank Danny McPherson and Eric Osterweil for
discussions related to this work. Also, thanks are due to Jared
Mauch, Jeff Haas, Warren Kumari, Amogh Dhamdhere, Jakob Heitz, Geoff
Huston, Randy Bush, Ruediger Volk, Andrei Robachevsky, Sue Hares,
Keyur Patel, Wes George, Chris Morrow, and Sandy Murphy for comments,
suggestions, and critique. The authors are also thankful to Padma
Krishnaswamy, Oliver Borchert, and Okhee Kim for their comments and
review.
10. References
10.1. Normative References
[RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
Protocol 4 (BGP-4)", RFC 4271, January 2006.
10.2. Informative References
[Cowie2010]
Cowie, J., "China's 18 Minute Mystery", Dyn Research/
Renesys Blog, November 2010,
<http://research.dyn.com/2010/11/
chinas-18-minute-mystery/>.
[Cowie2013]
Cowie, J., "The New Threat: Targeted Internet Traffic
Misdirection", Dyn Research/Renesys Blog, November 2013,
<http://research.dyn.com/2013/11/
mitm-internet-hijacking/>.
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Internet-Draft Route Leak Detection and Mitigation July 2015
[draft-dickson-sidr-route-leak-solns]
Dickson, B., "Route Leaks -- Proposed Solutions", IETF
Internet Draft (expired), March 2012,
<https://tools.ietf.org/html/draft-dickson-sidr-route-
leak-solns-01>.
[draft-ietf-idr-aspath-orf]
Patel, K. and S. Hares, "AS path Based Outbound Route
Filter for BGP-4", IETF Internet Draft (expired), August
2007, <https://tools.ietf.org/html/draft-ietf-idr-aspath-
orf-09>.
[draft-kunzinger-idrp-ISO10747-01]
Kunzinger, C., "Inter-Domain Routing Protocol (IDRP)",
IETF Internet Draft (expired), November 1994,
<https://tools.ietf.org/pdf/draft-kunzinger-idrp-
ISO10747-01.pdf>.
[Gao] Gao, L. and J. Rexford, "Stable Internet routing without
global coordination", IEEE/ACM Transactions on Networking,
December 2001, <http://www.cs.princeton.edu/~jrex/papers/
sigmetrics00.long.pdf>.
[Gill] Gill, P., Schapira, M., and S. Goldberg, "A Survey of
Interdomain Routing Policies", ACM SIGCOMM Computer
Communication Review, January 2014,
<https://www.cs.bu.edu/~goldbe/papers/survey.pdf>.
[Giotsas] Giotsas, V. and S. Zhou, "Valley-free violation in
Internet routing - Analysis based on BGP Community data",
IEEE ICC 2012, June 2012,
<http://www0.cs.ucl.ac.uk/staff/V.Giotsas/files/
giotsas.icc.2012.pdf>.
[Hiran] Hiran, R., Carlsson, N., and P. Gill, "Characterizing
Large-scale Routing Anomalies: A Case Study of the China
Telecom Incident", PAM 2013, March 2013,
<http://www3.cs.stonybrook.edu/~phillipa/papers/
CTelecom.html>.
[Huston2012]
Huston, G., "Leaking Routes", March 2012,
<http://labs.apnic.net/blabs/?p=139/>.
[Huston2014]
Huston, G., "What's so special about 512?", September
2014, <http://labs.apnic.net/blabs/?p=520/>.
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[I-D.ietf-grow-route-leak-problem-definition]
Sriram, K., Montgomery, D., McPherson, D., E.
Osterweil, and B. Dickson "Problem Definition and Classification of BGP
Route Leaks", draft-ietf-grow-route-leak-problem-
definition-02 (work in progress), July 2015.
[I-D.ietf-sidr-bgpsec-protocol]
Lepinski, M., "BGPsec Protocol Specification", draft-ietf-
sidr-bgpsec-protocol-12 (work in progress), June 2015.
[Kapela-Pilosov]
Pilosov, A. and T. Kapela, "Stealing the Internet: An
Internet-Scale Man in the Middle Attack", DEFCON-16 Las
Vegas, NV, USA, August 2008,
<https://www.defcon.org/images/defcon-16/dc16-
presentations/defcon-16-pilosov-kapela.pdf/>.
[Khare] Khare, V., Ju, Q., and B. Zhang, "Concurrent Prefix
Hijacks: Occurrence and Impacts", IMC 2012, Boston, MA,
November 2012, <http://www.cs.arizona.edu/~bzhang/
paper/12-imc-hijack.pdf/>.
[Labovitz]
Labovitz, C., "Additional Discussion of the April China
BGP Hijack Incident", Arbor Networks IT Security Blog,
November 2010,
<http://www.arbornetworks.com/asert/2010/11/additional-
discussion-of-the-april-china-bgp-hijack-incident/>.
[LRL] Khare, V., Ju, Q., and B. Zhang, "Large Route Leaks",
Project web page, 2012,
<http://nrl.cs.arizona.edu/projects/
lsrl-events-from-2003-to-2009/>.
[Luckie] Luckie, M., Huffaker, B., Dhamdhere, A., Giotsas, V., and
kc. claffy, "AS Relationships, Customer Cones, and
Validation", IMC 2013, October 2013,
<http://www.caida.org/~amogh/papers/asrank-IMC13.pdf>.
[Madory] Madory, D., "Why Far-Flung Parts of the Internet Broke
Today", Dyn Research/Renesys Blog, September 2014,
<http://research.dyn.com/2014/09/
why-the-internet-broke-today/>.
[Mauch] Mauch, J., "BGP Routing Leak Detection System", Project
web page, 2014,
<http://puck.nether.net/bgp/leakinfo.cgi/>.
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[Mauch-nanog]
Mauch, J., "Detecting Routing Leaks by Counting", NANOG-41
Albuquerque, NM, USA, October 2007,
<https://www.nanog.org/meetings/nanog41/presentations/
mauch-lightning.pdf/>.
[NIST-800-54]
Kuhn, D., Sriram, K., and D. Montgomery, "Border Gateway
Protocol Security", NIST Special Publication 800-54, July
2007, <http://csrc.nist.gov/publications/nistpubs/800-54/
SP800-54.pdf>.
[Paseka] Paseka, T., "Why Google Went Offline Today and a Bit about
How the Internet Works", CloudFare Blog, November 2012,
<http://blog.cloudflare.com/
why-google-went-offline-today-and-a-bit-about/>.
[proceedings-sixth-ietf]
Gross, P., "Proceedings of the April 22-24, 1987 Internet
Engineering Task Force", April 1987,
<https://www.ietf.org/proceedings/06.pdf>.
[RFC1105-obsolete]
Lougheed, K. and Y. Rekhter, "A Border Gateway Protocol
(BGP)", IETF RFC (obsolete), June 1989,
<https://tools.ietf.org/html/rfc1105>.
[RFC6811] Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R.
Austein, "BGP Prefix Origin Validation", RFC 6811, January
2013.
[RFC7454] Durand, J., Pepelnjak, I., and G. Doering, "BGP Operations
and Security", BCP 194, RFC 7454, February 2015.
[Toonk] Toonk, A., "What Caused Today's Internet Hiccup", August
2014, <http://www.bgpmon.net/
what-caused-todays-internet-hiccup/>.
[Wijchers]
Wijchers, B. and B. Overeinder, "Quantitative Analysis of
BGP Route Leaks", RIPE-69, November 2014,
<https://ripe69.ripe.net/presentations/157-RIPE-69-
Routing-WG.pdf>.
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[Zmijewski]
Zmijewski, E., "Indonesia Hijacks the World", Dyn
Research/Renesys Blog, April 2014,
<http://research.dyn.com/2014/04/
indonesia-hijacks-world/>.
Authors' Addresses
Kotikalapudi Sriram
US NIST
Email: ksriram@nist.gov
Doug Montgomery
US NIST
Email: dougm@nist.gov
Brian Dickson
Twitter, Inc.
Email: bdickson@twitter.com
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