Network Working Group P. Psenak
Internet-Draft A. Lindem
Intended status: Standards Track L. Ginsberg
Expires: December 25, 2017 Cisco Systems
W. Henderickx
Nokia
J. Tantsura
Individual
H. Gredler
RtBrick Inc.
June 23, 2017
OSPFv2 Link Traffic Engineering (TE) Attribute Reuse
draft-ppsenak-ospf-te-link-attr-reuse-05.txt
Abstract
Various link attributes have been defined in OSPFv2 in the context of
the MPLS Traffic Engineering (TE) and GMPLS. Many of these link
attributes can be used for purposes other than MPLS Traffic
Engineering or GMPLS. This documents defines how to distribute such
attributes in OSPFv2 for applications other than MPLS Traffic
Engineering or GMPLS purposes.
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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and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 25, 2017.
Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3
2. Link attributes examples . . . . . . . . . . . . . . . . . . 3
3. Advertising Link Attributes . . . . . . . . . . . . . . . . . 4
3.1. TE Opaque LSA . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Extended Link Opaque LSA . . . . . . . . . . . . . . . . 5
3.3. Selected Approach . . . . . . . . . . . . . . . . . . . . 5
4. Reused TE link attributes . . . . . . . . . . . . . . . . . . 6
4.1. Remote interface IP address . . . . . . . . . . . . . . . 6
4.2. Link Local/Remote Identifiers . . . . . . . . . . . . . . 6
4.3. Shared Risk Link Group (SRLG) . . . . . . . . . . . . . . 7
4.4. Extended Metrics . . . . . . . . . . . . . . . . . . . . 7
5. Advertisement of Application Specific Values . . . . . . . . 7
6. Deployment Considerations . . . . . . . . . . . . . . . . . . 10
7. Attribute Advertisements and Enablement . . . . . . . . . . . 10
8. Backward Compatibility . . . . . . . . . . . . . . . . . . . 11
9. Security Considerations . . . . . . . . . . . . . . . . . . . 11
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
12.1. Normative References . . . . . . . . . . . . . . . . . . 12
12.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
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1. Introduction
Various link attributes have been defined in OSPFv2 [RFC2328] in the
context of the MPLS traffic engineering and GMPLS. All these
attributes are distributed by OSPFv2 as sub-TLVs of the Link-TLV
advertised in the OSPFv2 TE Opaque LSA [RFC3630].
Many of these link attributes are useful outside of the traditional
MPLS Traffic Engineering or GMPLS. This brings its own set of
problems, in particular how to distribute these link attributes in
OSPFv2 when MPLS TE or GMPLS are not deployed or are deployed in
parallel with other applications that use these link attributes.
[RFC7855] discusses use cases/requirements for SR. Included among
these use cases is SRTE. If both RSVP-TE and SRTE are deployed in a
network, link attribute advertisements can be used by one or both of
these applications. As there is no requirement for the link
attributes advertised on a given link used by SRTE to be identical to
the link attributes advertised on that same link used by RSVP-TE,
there is a clear requirement to indicate independently which link
attribute advertisements are to be used by each application.
As the number of applications which may wish to utilize link
attributes may grow in the future, an additional requirement is that
the extensions defined allow the association of additional
applications to link attributes without altering the format of the
advertisements or introducing new backwards compatibility issues.
Finally, there may still be many cases where a single attribute value
can be shared among multiple applications, so the solution should
minimize advertising duplicate link/attribute when possible.
1.1. Requirements notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Link attributes examples
This section lists some of the link attributes originally defined for
MPLS Traffic Engineering that can be used for other purposes in
OSPFv2. The list doesn't necessarily contain all the required
attributes.
1. Remote Interface IP address [RFC3630] - OSPFv2 currently cannot
distinguish between parallel links between two OSPFv2 routers.
As a result, the two-way connectivity check performed during SPF
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may succeed when the two routers disagree on which of the links
to use for data traffic.
2. Link Local/Remote Identifiers - [RFC4203] - Used for the two-way
connectivity check for parallel unnumbered links. Also used for
identifying adjacencies for unnumbered links in Segment Routing
traffic engineering.
3. Shared Risk Link Group (SRLG) [RFC4203] - In IPFRR, the SRLG is
used to compute diverse backup paths [RFC5714].
4. Unidirectional Link Delay/Loss Metrics [RFC7471] - Could be used
for the shortest path first (SPF) computation using alternate
metrics within an OSPF area.
3. Advertising Link Attributes
This section outlines possible approaches for advertising link
attributes originally defined for MPLS Traffic Engineering purposes
or GMPLS when they are used for other applications.
3.1. TE Opaque LSA
One approach for advertising link attributes is to continue to use TE
Opaque LSA ([RFC3630]). There are several problems with this
approach:
1. Whenever the link is advertised in a TE Opaque LSA, the link
becomes a part of the TE topology, which may not match IP routed
topology. By making the link part of the TE topology, remote
nodes may mistakenly believe that the link is available for MPLS
TE or GMPLS, when, in fact, MPLS is not enabled on the link.
2. The TE Opaque LSA carries link attributes that are not used or
required by MPLS TE or GMPLS. There is no mechanism in a TE
Opaque LSA to indicate which of the link attributes are passed to
MPLS TE application and which are used by other applications
including OSPFv2 itself.
3. Link attributes used for non-TE purposes are partitioned across
multiple LSAs - the TE Opaque LSA and the Extended Link Opaque
LSA. This partitioning will require implementations to lookup
multiple LSAs to extract link attributes for a single link,
bringing needless complexity to OSPFv2 implementations.
The advantage of this approach is that there is no additional
standardization requirement to advertise the TE/GMPL attributes for
other applications. Additionally, link attributes are only
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advertised once when both OSPF TE and other applications are deployed
on the same link. This is not expected to be a common deployment
scenario.
3.2. Extended Link Opaque LSA
An alternative approach for advertising link attributes is to use
Extended Link Opaque LSAs as defined in [RFC7684]. This LSA was
defined as a generic container for distribution of the extended link
attributes. There are several advantages in using Extended Link LSA:
1. Advertisement of the link attributes does not make the link part
of the TE topology. It avoids any conflicts and is fully
compatible with the [RFC3630].
2. The TE Opaque LSA remains truly opaque to OSPFv2 as originally
defined in [RFC3630]. Its content is not inspected by OSPFv2 and
OSPFv2 acts as a pure transport.
3. There is clear distinction between link attributes used by TE and
link attributes used by other OSPFv2 applications.
4. All link attributes that are used by OSPFv2 applications are
advertised in a single LSA, the Extended Link Opaque LSA.
The disadvantage of this approach is that in rare cases, the same
link attribute is advertised in both the TE Opaque and Extended Link
Attribute LSAs. Additionally, there will be additional
standardization effort. However, this could also be viewed as an
advantage as the non-TE use cases for the TE link attributes are
documented and validated by the OSPF working group.
3.3. Selected Approach
It is RECOMMENDED to use the Extended Link Opaque LSA ([RFC7684] to
advertise any link attributes used for non-TE purposes in OSPFv2,
including those that have been originally defined for TE purposes.
TE link attributes used for TE purposes continue to use TE Opaque LSA
([RFC3630]).
It is also RECOMMENDED to keep the format of the link attribute TLVs
that have been defined for TE purposes unchanged even when they are
used for non-TE purposes.
Finally, it is RECOMMENDED to allocate unique code points for link
attribute TLVs that have been defined for TE purposes for the OSPFv2
Extended Link TLV Sub-TLV Registry as defined in [RFC7684]. For each
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reused TLV, the code point will be defined in an IETF document along
with the expected usecase(s).
4. Reused TE link attributes
This section defines the use case and code points for the OSPFv2
Extended Link TLV Sub-TLV Registry for some of the link attributes
that have been originally defined for TE or GMPLS purposes.
4.1. Remote interface IP address
The OSPFv2 description of an IP numbered point-to-point adjacency
does not include the remote IP address. As described in Section 2,
this makes the two-way connectivity check ambiguous in the presence
of the parallel point-to-point links between two OSPFv2 routers.
The Remote IP address of the link can also be used for Segment
Routing traffic engineering to identify the link in a set of parallel
links between two OSPFv2 routers
[I-D.ietf-ospf-segment-routing-extensions]. Similarly, the remote IP
address is useful in identifying individual parallel OSPF links
advertised in BGP Link-State as described in
[I-D.ietf-idr-ls-distribution].
To advertise the Remote interface IP address in the OSPFv2 Extended
Link TLV, the same format of the sub-TLV as defined in section 2.5.4.
of [RFC3630] is used and TLV type TBD1 is used.
4.2. Link Local/Remote Identifiers
The OSPFv2 description of an IP unnumbered point-to-point adjacency
does not include the remote link identifier. As described in
Section 2, this makes the two-way connectivity check ambiguous in the
presence of the parallel point-to-point IP unnumbered links between
two OSPFv2 routers.
The local and remote link identifiers can also be used for Segment
Routing traffic engineering to identify the link in a set of parallel
IP unnumbered links between two OSPFv2 routers
[I-D.ietf-ospf-segment-routing-extensions]. Similarly, these
identifiers are useful in identifying individual parallel OSPF links
advertised in BGP Link-State as described in
[I-D.ietf-idr-ls-distribution].
To advertise the link Local/Remote identifiers in the OSPFv2 Extended
Link TLV, the same format of the sub-TLV as defined in section 1.1.
of [RFC4203] is used and TLV type TBD2 is used.
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4.3. Shared Risk Link Group (SRLG)
The SRLG of a link can be used in IPFRR to compute a backup path that
does not share any SRLG group with the protected link.
To advertise the SRLG of the link in the OSPFv2 Extended Link TLV,
the same format of the sub-TLV as defined in section 1.3. of
[RFC4203] is used and TLV type TBD3 is used.
4.4. Extended Metrics
[RFC3630] defines several link bandwidth types. [RFC7471] defines
extended link metrics that are based on link bandwidth, delay and
loss characteristics. All these can be used to compute best paths
within an OSPF area to satisfy requirements for bandwidth, delay
(nominal or worst case) or loss.
To advertise extended link metrics in the OSPFv2 Extended Link TLV,
the same format of the sub-TLVs as defined in [RFC7471] is used with
following TLV types:
TBD4 - Unidirectional Link Delay
TBD5 - Min/Max Unidirectional Link Delay
TBD6 - Unidirectional Delay Variation
TBD7 - Unidirectional Link Loss
TBD8 - Unidirectional Residual Bandwidth
TBD9 - Unidirectional Available Bandwidth
TBD10 - Unidirectional Utilized Bandwidth
5. Advertisement of Application Specific Values
Multiple applications can utilize link attributes that are flooded by
OSPFv2. Some examples of applications using the link attributes are
Segment Routing Traffic Engineering and LFA [RFC5286].
In some cases the link attribute only has a single value that is
applicable to all applications. An example is a Remote interface IP
address [Section 4.1] or Link Local/Remote Identifiers [Section 4.2].
In some cases the link attribute MAY have different values for
different applications. An example could be SRLG [Section 4.3],
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where values used by LFA could be different then the values used by
Segment Routing Traffic Engineering.
To allow advertisement of the application specific values of the link
attribute, a new Extended Link Attribute sub-TLV of the Extended Link
TLV [RFC7471] is defined. The Extended Link Attribute sub-TLV is an
optional sub-TLV and can appear multiple times in the Extended Link
TLV. It has following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SABML | UDABML | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Standard Application Bit-Mask |
+- -+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| User Defined Application Bit-Mask |
+- -+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Attribute sub-sub-TLVs |
+- -+
| ... |
where:
Type: TBD11, suggested value 14
Length: variable
SABML: Standard Application Bit-Mask Length. If the Standard
Application Bit-Mask is not present, the Standard Application Bit-
Mask Length MUST be set to 0.
UDABML: User Defined Application Bit-Mask Length. If the User
Defined Application Bit-Mask is not present, the User Defined
Application Bit-Mask Length MUST be set to 0.
Standard Application Bit-Mask: Optional set of bits, where each
bit represents a single standard application. The following bits
are defined by this document:
Bit-0: RSVP Traffic Engineering
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Bit-1: Segment Routing Traffic Engineering
Bit-2: Loop Free Alternate (LFA). Includes all LFA types.
User Defined Application Bit-Mask: Optional set of bits, where
each bit represents a single user defined application.
Standard Application Bits are defined/sent starting with Bit 0.
Additional bit definitions that may be defined in the future SHOULD
be assigned in ascending bit order so as to minimize the number of
octets that will need to be transmitted.
User Defined Application bits have no relationship to Standard
Application bits and are NOT managed by IANA or any other standards
body. It is recommended that bits are used starting with Bit 0 so as
to minimize the number of octets required to advertise all of them.
Undefined bits in both Bit-Masks MUST be transmitted as 0 and MUST be
ignored on receipt. Bits that are NOT transmitted MUST be treated as
if they are set to 0 on receipt.
If the link attribute advertisement is limited to be used by a
specific set of applications, corresponding Bit-Masks MUST be present
and application specific bit(s) MUST be set for all applications that
use the link attributes advertised in the Extended Link Attribute
sub-TLV.
Application Bit-Masks apply to all link attributes that support
application specific values and are advertised in the Extended Link
Attribute sub-TLV.
The advantage of not making the Application Bit-Masks part of the
attribute advertisement itself is that we can keep the format of the
link attributes that have been defined previously and reuse the same
format when advertising them in the Extended Link Attribute sub-TLV.
If the link attribute is advertised and there is no Application Bit-
Mask present in the Extended Link Attribute Sub-TLV, the link
attribute advertisement MAY be used by any application. If, however,
another advertisement of the same link attribute includes any
Application Bit-Mask in the Extended Link Attribute sub-TLV,
applications that are listed in the Application Bit-Masks of such
Extended Link Attribute sub-TLV SHOULD use the attribute
advertisement which has the application specific bit set in the
Application Bit-Masks.
If the same application is listed in the Application Bit-Masks of
more then one Extended Link Attribute sub-TLV, the application SHOULD
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use the first advertisement and ignore any subsequent advertisements
of the same attribute. This situation SHOULD be logged as an error.
This document defines the set of link attributes for which the
Application Bit-Masks may be advertised. If any of the Application
Bit-Masks is included in the Extended Link Attribute sub-TLV that
advertises any link attribute(s) NOT listed below, the Application
Bit-Masks MUST NOT be used for such link attribute(s). It MUST be
used for those attribute(s) that support application specific values.
Documents which define new link attributes MUST state whether the new
attributes support application specific values. The link attributes
to which the Application Bit-Masks may apply are:
- Shared Risk Link Group
- Unidirectional Link Delay
- Min/Max Unidirectional Link Delay
- Unidirectional Delay Variation
- Unidirectional Link Loss
- Unidirectional Residual Bandwidth
- Unidirectional Available Bandwidth
- Unidirectional Utilized Bandwidth
6. Deployment Considerations
If link attributes are advertised associated with zero length
application bit masks for both standard applications and user defined
applications, then that set of link attributes MAY be used by any
application. If support for a new application is introduced on any
node in a network in the presence of such advertisements, these
advertisements MAY be used by the new application. If this is not
what is intended, then existing advertisements MUST be readvertised
with an explicit set of applications specified before a new
application is introduced.
7. Attribute Advertisements and Enablement
This document defines extensions to support the advertisement of
application specific link attributes. The presence or absence of
link attribute advertisements for a given application on a link does
NOT indicate the state of enablement of that application on that
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link. Enablement of an application on a link is controlled by other
means.
For some applications, the concept of enablement is implicit. For
example, SRTE implicitly is enabled on all links which are part of
the Segment Routing enabled topology. Advertisement of link
attributes supports constraints which may be applied when specifying
an explicit path through that topology.
For other applications enablement is controlled by local
configuration. For example, use of a link as an LFA can be
controlled by local enablement/disablement and/or the use of
administrative tags.
It is an application specific policy as to whether a given link can
be used by that application even in the absence of any application
specific link attributes.
8. Backward Compatibility
Link attributes may be concurrently advertised in both the TE Opaque
LSA [RFC3630] and the Extended Link Opaque LSA [RFC7684].
In fact, there is at least one OSPF implementation that utilizes the
link attributes advertised in TE Opaque LSAs [RFC3630] for Non-RSVP
TE applications. For example, this implementation of LFA and remote
LFA utilizes links attributes such as Shared Risk Link Groups (SRLG)
[RFC4203] and Admin Group [[RFC3630]advertised in TE Opaque LSAs.
These applications are described in [RFC5286], [RFC7490],
[I-D.ietf-rtgwg-lfa-manageability] and
[I-D.psarkar-rtgwg-rlfa-node-protection].
When an OSPF routing domain includes routers using link attributes
from TE Opaque LSAs for Non-RSVP TE applications such as LFA, OSPF
routers in that domain should continue to advertise such TE Opaque
LSAs. If there are also OSPF routers using the link attributes
described herein for any application, OSPF routers in the routing
domain will also need to advertise these attributes in OSPF Extended
Link Attributes LSAs [RFC7684]. In such a deployment, the advertised
attributes SHOULD be the same and Non-RSVP application access to link
attributes is a matter of local policy.
9. Security Considerations
Implementations must assure that malformed TLV and Sub-TLV
permutations do not result in errors that cause hard OSPFv2 failures.
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10. IANA Considerations
OSPFv2 Extended Link TLV Sub-TLVs registry [RFC7684] defines sub-TLVs
at any level of nesting for OSPFv2 Extended Link TLVs. This
specification updates OSPFv2 Extended Link TLV sub-TLVs registry with
the following TLV types:
TBD1 (4 Recommended) - Remote interface IP address
TBD2 (5 Recommended) - Link Local/Remote Identifiers
TBD3 (6 Recommended) - Shared Risk Link Group
TBD4 (7 Recommended) - Unidirectional Link Delay
TBD5 (8 Recommended) - Min/Max Unidirectional Link Delay
TBD6 (9 Recommended) - Unidirectional Delay Variation
TBD7 (10 Recommended) - Unidirectional Link Loss
TBD8 (11 Recommended) - Unidirectional Residual Bandwidth
TBD9 (12 Recommended) - Unidirectional Available Bandwidth
TBD10 (13 Recommended) - Unidirectional Utilized Bandwidth
TBD11 (14 Recommended) - Extended Link Attribute
This specification defines a new Link-Attribute-Applicability
Application Bits registry and defines following bits:
Bit-0 - Segment Routing Traffic Engineering
Bit-1 - LFA
11. Acknowledgments
Thanks to Chris Bowers for his review and comments.
12. References
12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
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[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630,
DOI 10.17487/RFC3630, September 2003,
<http://www.rfc-editor.org/info/rfc3630>.
[RFC5714] Shand, M. and S. Bryant, "IP Fast Reroute Framework",
RFC 5714, DOI 10.17487/RFC5714, January 2010,
<http://www.rfc-editor.org/info/rfc5714>.
[RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,
Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute
Advertisement", RFC 7684, DOI 10.17487/RFC7684, November
2015, <http://www.rfc-editor.org/info/rfc7684>.
12.2. Informative References
[I-D.ietf-idr-ls-distribution]
Gredler, H., Medved, J., Previdi, S., Farrel, A., and S.
Ray, "North-Bound Distribution of Link-State and TE
Information using BGP", draft-ietf-idr-ls-distribution-13
(work in progress), October 2015.
[I-D.ietf-ospf-segment-routing-extensions]
Psenak, P., Previdi, S., Filsfils, C., Gredler, H.,
Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", draft-ietf-ospf-segment-
routing-extensions-16 (work in progress), May 2017.
[I-D.ietf-rtgwg-lfa-manageability]
Litkowski, S., Decraene, B., Filsfils, C., Raza, K., and
M. Horneffer, "Operational management of Loop Free
Alternates", draft-ietf-rtgwg-lfa-manageability-11 (work
in progress), June 2015.
[I-D.psarkar-rtgwg-rlfa-node-protection]
psarkar@juniper.net, p., Gredler, H., Hegde, S., Bowers,
C., Litkowski, S., and H. Raghuveer, "Remote-LFA Node
Protection and Manageability", draft-psarkar-rtgwg-rlfa-
node-protection-05 (work in progress), June 2014.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<http://www.rfc-editor.org/info/rfc2328>.
[RFC4203] Kompella, K., Ed. and Y. Rekhter, Ed., "OSPF Extensions in
Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005,
<http://www.rfc-editor.org/info/rfc4203>.
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[RFC5286] Atlas, A., Ed. and A. Zinin, Ed., "Basic Specification for
IP Fast Reroute: Loop-Free Alternates", RFC 5286,
DOI 10.17487/RFC5286, September 2008,
<http://www.rfc-editor.org/info/rfc5286>.
[RFC7471] Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
Previdi, "OSPF Traffic Engineering (TE) Metric
Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
<http://www.rfc-editor.org/info/rfc7471>.
[RFC7490] Bryant, S., Filsfils, C., Previdi, S., Shand, M., and N.
So, "Remote Loop-Free Alternate (LFA) Fast Reroute (FRR)",
RFC 7490, DOI 10.17487/RFC7490, April 2015,
<http://www.rfc-editor.org/info/rfc7490>.
[RFC7855] Previdi, S., Ed., Filsfils, C., Ed., Decraene, B.,
Litkowski, S., Horneffer, M., and R. Shakir, "Source
Packet Routing in Networking (SPRING) Problem Statement
and Requirements", RFC 7855, DOI 10.17487/RFC7855, May
2016, <http://www.rfc-editor.org/info/rfc7855>.
Authors' Addresses
Peter Psenak
Cisco Systems
Apollo Business Center
Mlynske nivy 43
Bratislava, 821 09
Slovakia
Email: ppsenak@cisco.com
Acee Lindem
Cisco Systems
301 Midenhall Way
Cary, NC 27513
USA
Email: acee@cisco.com
Psenak, et al. Expires December 25, 2017 [Page 14]
Internet-Draft OSPFv2 Link TE Attributes Reuse June 2017
Les Ginsberg
Cisco Systems
821 Alder Drive
MILPITAS, CA 95035
USA
Email: ginsberg@cisco.com
Wim Henderickx
Nokia
Copernicuslaan 50
Antwerp, 2018 94089
Belgium
Email: wim.henderickx@nokia.com
Jeff Tantsura
Individual
USA
Email: jefftant.ietf@gmail.com
Hannes Gredler
RtBrick Inc.
Email: hannes@rtbrick.com
Psenak, et al. Expires December 25, 2017 [Page 15]