Signaling RSVP-TE tunnels on a shared MPLS forwarding plane
draft-sitaraman-mpls-rsvp-shared-labels-00
The information below is for an old version of the document.
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Harish Sitaraman , Vishnu Pavan Beeram , Tejal Parikh | ||
| Last updated | 2017-03-10 | ||
| Replaced by | draft-ietf-mpls-rsvp-shared-labels, RFC 8577 | ||
| Stream | (None) | ||
| Formats | plain text htmlized pdfized bibtex | ||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-sitaraman-mpls-rsvp-shared-labels-00
MPLS Working Group H. Sitaraman
Internet-Draft V. Beeram
Intended status: Standards Track Juniper Networks
Expires: September 11, 2017 T. Parikh
Verizon
March 10, 2017
Signaling RSVP-TE tunnels on a shared MPLS forwarding plane
draft-sitaraman-mpls-rsvp-shared-labels-00.txt
Abstract
As the scale of MPLS RSVP-TE LSPs has grown, various implementation
recommendations have been proposed to manage control plane state.
However, the forwarding plane footprint of labels at a transit LSR
has remained proportional to the total LSP state in the control
plane. This draft defines a mechanism to prevent the label space
limit on an LSR from being a constraint to control plane scaling on
that node. It introduces the notion of pre-installed per TE link
'pop labels' that are shared by MPLS RSVP-TE LSPs that traverse these
links and thus significantly reducing the forwarding plane state
required. This couples the feature benefits of the RSVP-TE control
plane with the simplicity of the Segment Routing MPLS forwarding
plane. This document also introduces the ability to mix different
types of label operations along the path of the LSP, thereby allowing
the ingress or an external controller to influence how to optimally
place a LSP.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on September 11, 2017.
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Copyright Notice
Copyright (c) 2017 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 . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . 4
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Allocation of pop labels . . . . . . . . . . . . . . . . . . 4
5. RSVP-TE pop and forward tunnel setup . . . . . . . . . . . . 4
6. Mixing pop and swap labels in a RSVP-TE tunnel . . . . . . . 6
7. Distributing label stack imposition . . . . . . . . . . . . . 7
8. Facility backup protection . . . . . . . . . . . . . . . . . 7
8.1. Link Protection . . . . . . . . . . . . . . . . . . . . . 7
8.2. Node Protection . . . . . . . . . . . . . . . . . . . . . 8
9. Quantifying pop labels . . . . . . . . . . . . . . . . . . . 8
10. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 9
10.1. Requirements . . . . . . . . . . . . . . . . . . . . . . 9
10.2. Attributes Flags TLV: Pop Label . . . . . . . . . . . . 9
10.3. RRO Label Subobject Flag: Pop Label . . . . . . . . . . 10
10.4. Attributes TLV: Label Stack Imposition TLV . . . . . . . 10
11. OAM considerations . . . . . . . . . . . . . . . . . . . . . 11
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
13. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 11
14. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
14.1. Attribute Flags: Pop Label . . . . . . . . . . . . . . . 11
14.2. Attribute TLV: Label Stack Imposition TLV . . . . . . . 11
14.3. Record Route Label Sub-object Flags: Pop Label . . . . . 12
15. Security Considerations . . . . . . . . . . . . . . . . . . . 12
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
16.1. Normative References . . . . . . . . . . . . . . . . . . 12
16.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
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1. Introduction
Various RSVP-TE scaling recommendations [RFC2961]
[I-D.ietf-teas-rsvp-te-scaling-rec] have been proposed for
implementations to adopt guidelines that would allow the RSVP-TE
[RFC3209] control plane to scale better. The forwarding plane state
required to handle the equivalent control plane state remains
unchanged and is proportional to the total LSP state in the control
plane. The motivation of this draft is to prevent the platform
specific label space limit on an LSR from being a constraint to
pushing the limits of control plane scaling on that node.
This document proposes the allocation of a 'pop label' by a LSR for
each of its TE links. The label is installed in the MPLS forwarding
plane with a pop label operation and to forward the received packet
over the TE link. This label is sent normally by the LSR in the
Label object in the Resv message as LSPs are setup. The ingress LER
SHOULD construct and push a stack of labels [RFC3031] as received in
the Record Route object(RRO) in the Resv message.
This pop and forward data plane behavior is similar to that used by
Segment Routing (SR) [I-D.ietf-spring-segment-routing] using a MPLS
forwarding plane and a series of adjacency segments. The RSVP-TE pop
and forward tunnels can co-exist with SR LSPs as described in
[I-D.sitaraman-sr-rsvp-coexistence-rec].
RSVP-TE using a pop and forward data plane offers the following
benefits:
1. Shared forwarding plane: The transit label on a TE link is shared
among RSVP-TE tunnels traversing the link and is used independent
of the ingress and egress of the LSPs.
2. Faster LSP setup time: The forwarding plane state is not
programmed during LSP setup and teardown resulting in faster LSP
setup time.
3. Hitless routes: New transit labels are not required on complete
path overlap during make-before-break (MBB) resulting in a faster
MBB event. This avoids the ingress LER and the services that
might be using the tunnel from needing to update its forwarding
plane with new tunnel labels. Periodic MBB events are relatively
common in networks that deploy auto-bandwidth on RSVP-TE LSPs to
monitor bandwidth utilization and periodically adjust LSP
bandwidth.
4. Mix and match labels: Both 'pop' and 'swap' labels can be mixed
across transit hops for a single RSVP-TE tunnel (see Section 6).
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This allows local policy at an ingress or path computation engine
to influence RSVP-TE to mix and match different types of labels
across a LSP path.
No additional extensions are required to IGP-TE in order to support
this pop and forward data plane. Functionalities such as bandwidth
admission control, LSP priorities, preemption, auto-bandwidth and
Fast Reroute continue to work with this forwarding plane.
2. Conventions used in this document
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 RFC 2119 [RFC2119].
3. Terminology
Pop label: An incoming label at a LSR that will be popped and
forwarded over a specific TE link to a neighbor.
Swap label: An incoming label at a LSR that will be swapped to an
outgoing label and forwarded over a specific downstream TE link.
Pop and forward data plane: A forwarding plane where every LSR along
the path uses a pop label.
RSVP-TE pop and forward tunnel: A MPLS RSVP-TE tunnel that uses a pop
and forward data plane.
4. Allocation of pop labels
A LSR SHOULD allocate a unique pop label for each TE link. The
forwarding action for the pop label should it appear on top of the
label stack MUST be to pop the label and forward the packet over the
TE link to the downstream neighbor of the RSVP-TE tunnel. Multiple
labels MAY be allocated for the TE link to accommodate tunnels
requesting no protection, link-protection and node-protection over
the specific TE link.
5. RSVP-TE pop and forward tunnel setup
This section provides an example of how the RSVP-TE signaling
procedure works to setup a tunnel utilizing a pop and forward data
plane. The sample topology below will be used to explain the setup.
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Labels shown at each node are pop labels for that neighbor
+---+100 +---+150 +---+200 +---+250 +---+
| A |-----| B |-----| C |-----| D |-----| E |
+---+ +---+ +---+ +---+ +---+
|110 |450 |550 |650 |850
| | | | |
| |400 |500 |600 |800
| +---+ +---+ +---+ +---+
+-------| F |-----|G |-----|H |-----|I |
+---+300 +---+350 +---+700 +---+
Figure 1: Pop and forward label topology
RSVP-TE tunnel T1: From A to E on path A-B-C-D-E
RSVP-TE tunnel T2: From F to E on path F-B-C-D-E
Both tunnels share the TE links B-C, C-D and D-E.
As RSVP-TE signals the setup (using the pop label attributes flag
defined in Section 10.2) of tunnel T1, when LSR D receives the Resv
message from the egress E, it checks the next-hop TE link (D-E) and
provides the pop label (250) in the Resv message for the tunnel. The
label is sent in the Label object and is also recorded in the Label
sub-object (using the pop label bit defined in Section 10.3) carried
in the RRO. Similarly, C provides the pop label (200) for the next-
hop TE link C-D and B provides the pop label (150) for the next-hop
TE link B-C. For the tunnel T2, the transit LSRs provide the same
pop labels as described for tunnel T1.
Both LER A and F will push the same stack of labels {150(top), 200,
250} for tunnels T1 and T2 respectively. It should be noted that a
transit LSR does not use the pop label provided in the label object
by its downstream LSR in the NHLFE as the outgoing label. The
recorded labels in the RRO are of interest to the ingress LER in
order to construct a stack of labels.
If there were another RSVP-TE tunnel T3 from F to I on path
F-B-C-D-E-I, then this would also share the TE links B-C, C-D and D-E
and additionally traverse link E-I. The label stack used by F would
be {150(top), 200, 250, 850}. Hence, regardless of the ingress and
egress LERs from where the LSPs start and end, they will share LSR
labels at shared hops in the pop and forward data plane.
There MAY be local operator policy at the ingress LER that influences
the maximum depth of the label stack that can be pushed for a RSVP-TE
pop and forward tunnel. Prior to signaling the LSP, if the ingress
LER decides that it would be unable to push the entire label stack
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should every transit hop provide a pop label, then the LER can choose
to either not signal a RSVP-TE pop and forward tunnel or can adopt
techniques mentioned in Section 6 or Section 7.
6. Mixing pop and swap labels in a RSVP-TE tunnel
Labels can be mixed across transit hops in a single MPLS RSVP-TE LSP.
Certain LSRs can use pop labels and others can use swap labels. The
ingress can construct a label stack appropriately based on what type
of label is recorded from every transit LSR.
Labels shown at each node are pop labels for that TE link. (#) are
swap labels.
(#) (#)
+---+100 +---+150 +---+200 +---+250 +---+
| A |-----| B |-----| C |-----| D |-----| E |
+---+ +---+ +---+ +---+ +---+
|110 |450 |550 |650 |850
| | | | |
| |400 |500 |600 |800
| +---+ +---+ +---+ +---+
+-------| F |-----|G |-----|H |-----|I |
+---+300 +---+350 +---+700 +---+
Figure 2: Mix pop and swap label topology
If the transit LSR is allocating a swap label to be sent upstream in
the Resv, then the label operation in the NHLFE MUST be a swap to any
label received from the downstream LSR. If the transit LSR is using
a pop label to be sent upstream in the Resv, then the label operation
in the NHLFE MUST be a pop and forward regardless of any label
received from the downstream LSR.
The ingress LER MUST check the type of label received from each
transit hop as recorded in the RRO in the Resv message and generate
the appropriate label stack to use for the RSVP-TE tunnel.
The following logic could be used by the ingress LER while
constructing the label stack:
Each RRO label sub-object SHOULD be processed starting with the label
sub-object from the first downstream hop. Any label provided by the
first downstream hop MUST always be pushed on the label stack
regardless of the label type. If the label type is a pop label, then
any label from the next downstream hop MUST also be pushed on the
constructed label stack. If the label type is a swap label, then any
label from the next downstream hop MUST NOT be pushed on the
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constructed label stack. For example, the LSP from A to I using path
A-B-C-D-E-I will use a label stack of {150(top), 200}.
Signaling extensions for the ingress LER to request a certain type of
label from a particular hop is defined in Section 10.2. A Hop-Count
value of 1 (Label Stack Imposition Attribute) SHOULD be used for the
specific hops to allocate a swap label.
7. Distributing label stack imposition
One or more transit LSRs can assist the ingress LER by imposing part
of the label stack required for the path. From Figure 1, ingress LER
A can use the assistance of transit LSRs to push labels downstream of
that LSR. For example, LER A can push label 150 and LSR C can push
{200(top), 250} for the LSP taking path A-B-C-D-E.
The ingress LER can request one or more specific transit hops to
handle pushing labels for N of its downstream hops. To achieve this
request properly, the ingress can learn the label stack depth push
limit of the transit LSRs. The mechanism by which the ingress or
controller (hosting the path computation element) learns this
information is outside the scope of this document. The particular
transit hops SHOULD allocate a swap label that will result in that
label being replaced and a set of labels pushed to accommodate N
downstream hops.
Signaling extensions for the ingress LER to request one or more
transit LSRs to handle label stack imposition for N downstream hops
or for the transit hop to indicate to the ingress that it can handle
label stack imposition for N downstream hops is defined in
Section 10.2. The Hop-Count field (Label Stack Imposition Attribute)
can be used to indicate the value of N.
8. Facility backup protection
The following section describe how link and node protection works
with facility backup protection [RFC4090] for the RSVP-TE pop and
forward tunnels.
8.1. Link Protection
To provide link protection at a PLR with a pop and forward data
plane, the LSR SHOULD allocate a separate pop label for the TE link
that will be used for RSVP-TE tunnels that request link-protection
from the ingress. No signaling extensions are required to support
link protection for RSVP-TE tunnels over the pop and forward data
plane.
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(*) are pop labels to offer link protection for that TE link
101(*) 151(*) 201(*) 251(*)
+---+100 +---+150 +---+200 +---+250 +---+
| A |-----| B |-----| C |-----| D |-----| E |
+---+ +---+ +---+ +---+ +---+
|110 |450 |550 |650 |850
| | | | |
| |400 |500 |600 |800
| +---+ +---+ +---+ +---+
+-------| F |-----|G |-----|H |-----|I |
+---+300 +---+350 +---+700 +---+
Figure 3: Link protection topology
At each LSR, link protected pop labels can be allocated for each TE
link and a link protecting facility backup LSP can be created to
protect the TE link. This label can be sent by the LSR for LSPs
requesting link-protection over the specific TE link. Since the
facility backup terminates at the next-hop (merge point), the
incoming label on the packet will be what the merge point expects.
As an example, LSR B can install a facility backup LSP for the link
protected pop label 151. When the TE link B-C is up, LSR B will pop
151 and send the packet to C. If the TE link B-C is down, the LSR
can pop 151 and send the packet via the facility backup to C.
8.2. Node Protection
The solutions for the PLR to provide node-protection for the pop and
forward RSVP-TE tunnel will be explained in the next version of the
document.
9. Quantifying pop labels
This section attempts to quantify the number of labels required in
the forwarding plane to provide sharing of labels across RSVP-TE pop
and forward tunnels. A MPLS RSVP-TE tunnel offers either no
protection, link protection or node protection and only one of these
labels is required per tunnel during signaling. The scale of the
number of pop labels required per LSR can be deduced as follows:
o For a LSR having X neighbors reachable across Y interfaces, the
number of unprotected pop labels = X
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o For a PLR having X neighbors reachable across Y interfaces, number
of link protected pop labels = X
o For a PLR having X neighbors, each having Nx neighbors (i.e. next-
nexthop for PLR), number of node protected pop labels =
SUM_OF_ALL(Nx)
Total number of pop labels = Unprotected pop labels + link protected
pop labels + node protected pop labels = 2X + SUM(Nm)
10. Protocol Extensions
10.1. Requirements
The functionality discussed in this document imposes the following
requirements on the signaling protocol.
o The Ingress of the LSP SHOULD have the ability to mandate/request
the use and recording of pop labels at all hops along the path of
the LSP.
o When the use of pop labels is mandated/requested for the entire
path,
the node recording the pop label SHOULD have the ability to
indicate if the recorded label is a pop label.
the ingress SHOULD have the ability to override this path
specific behavior by
explicitly mandating specific hops to not use pop labels (or)
mandating specific hops to share the onus of imposing the
label stack (and also specifying the desired number of hops
that need to be accounted for at that node)
the node which was mandated to share the onus of imposing the
label stack SHOULD have the ability to indicate the actual number
of hops that it can account for.
10.2. Attributes Flags TLV: Pop Label
Bit Number (TBD1): Pop Label
The presence of this in the LSP_ATTRIBUTES/LSP_REQUIRED_ATTRIBUTES
object of a Path message indicates that the ingress has requested/
mandated the use and recording of pop labels at all hops along the
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path of this LSP. When a node that does not cater to the request/
mandate receives a Path message carrying the LSP_REQUIRED_ATTRIBUTES
object with this flag set, it MUST send a PathErr message with an
error code of 'routing problem' and an error value of 'pop label
usage failure'.
10.3. RRO Label Subobject Flag: Pop Label
Bit Number (TBD2): Pop Label
The presence of this flag indicates that the recorded label is a pop
label. This flag SHOULD be used by a node only if the use and
recording of pop labels is requested/mandated for this LSP.
10.4. Attributes TLV: Label Stack Imposition TLV
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved | Hop-Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Attribute TLV Type: TBD3
The presence of this in the HOP_ATTRIBUTES subobject [RFC7570] of an
ERO object in the Path message mandates the hop identified by the
preceding IPv4 or IPv6 or Unnumbered Interface ID subobject to share
the onus of imposing the label stack. This attribute MUST be used
only if the use and recording of pop labels is requested/mandated for
this LSP (only if Pop Label flag is present in the LSP_ATTRIBUTES/
LSP_REQUIRED_ATTRIBUTES object). If the node is not able to comply
with this mandate, it MUST send a PathErr message with an error code
of 'routing problem' and an error value of 'label stack imposition
failure'.
The Hop-Count field specifies the desired number of hops that this
node needs to account for. A Hop-Count value of 0 is considered
invalid and a value of 1 implies that this hop perform a normal swap
or pop (if this hop is PHP) operation towards the next downstream
hop.
The presence of this in the HOP_ATTRIBUTES subobject of an RRO object
in the RESV message indicates that the hop identified by the
preceding IPv4 or IPv6 or Unnumbered Interface ID subobject is
sharing the onus of imposing the label stack. The Hop-Count field
specifies the actual number of hops that this node can account for.
This should not be included in the RESV message unless this TLV is
also present in the corresponding Path message for this hop.
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11. OAM considerations
Any extensions necessary for MPLS LSP traceroute for the RSVP-TE pop
and forward tunnel will be explained in the next version of the
document.
12. Acknowledgements
The authors would like to thank Adrian Farrel, Kireeti Kompella,
Markus Jork and Ross Callon for their input from discussions.
13. Contributors
The following individuals contributed to this document:
Raveendra Torvi
Juniper Networks
Email: rtorvi@juniper.net
Chandra Ramachandran
Juniper Networks
Email: csekar@juniper.net
14. IANA Considerations
14.1. Attribute Flags: Pop Label
IANA manages the 'Attribute Flags' registry as part of the 'Resource
Reservation Protocol-Traffic Engineering (RSVP-TE) Parameters'
registry located at http://www.iana.org/assignments/rsvp-te-
parameters. This document introduces a new Attribute Flag.
Bit Name Attribute Attribute RRO ERO Reference
No. FlagsPath FlagsResv
TBD1 Pop Label Yes No No No This document
(Section 5)
14.2. Attribute TLV: Label Stack Imposition TLV
IANA manages the "Attribute TLV Space" registry as part of the
'Resource Reservation Protocol-Traffic Engineering (RSVP-TE)
Parameters' registry located at http://www.iana.org/assignments/rsvp-
te-parameters. This document introduces a new Attribute TLV.
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Type Name Allowed on Allowed on Allowed on Reference
LSP LSP REQUIRED LSP Hop
ATTRIBUTES ATTRIBUTES Attributes
TBD3 Label No No Yes This document
Stack (Section 7)
Imposition
TLV
14.3. Record Route Label Sub-object Flags: Pop Label
IANA manages the 'Record Route Object Sub-object Flags' registry as
part of the 'Resource Reservation Protocol-Traffic Engineering (RSVP-
TE) Parameters' registry located at http://www.iana.org/assignments/
rsvp-te-parameters. This registry currently does not include Label
Sub-object Flags. This document proposes the addition of a new sub-
registry for Label Sub-object Flags as shown below.
Flag Name Reference
0x1 Global Label RFC 3209
TBD2 Pop Label This document (Section 5)
15. Security Considerations
This document does not introduce new security issues. The security
considerations pertaining to the original RSVP protocol [RFC2205] and
RSVP-TE [RFC3209] and those that are described in [RFC5920] remain
relevant.
16. References
16.1. 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>.
[RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
September 1997, <http://www.rfc-editor.org/info/rfc2205>.
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[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<http://www.rfc-editor.org/info/rfc3031>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<http://www.rfc-editor.org/info/rfc3209>.
[RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
DOI 10.17487/RFC4090, May 2005,
<http://www.rfc-editor.org/info/rfc4090>.
[RFC7570] Margaria, C., Ed., Martinelli, G., Balls, S., and B.
Wright, "Label Switched Path (LSP) Attribute in the
Explicit Route Object (ERO)", RFC 7570,
DOI 10.17487/RFC7570, July 2015,
<http://www.rfc-editor.org/info/rfc7570>.
16.2. Informative References
[I-D.ietf-spring-segment-routing]
Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
and R. Shakir, "Segment Routing Architecture", draft-ietf-
spring-segment-routing-11 (work in progress), February
2017.
[I-D.ietf-teas-rsvp-te-scaling-rec]
Beeram, V., Minei, I., Shakir, R., Pacella, D., and T.
Saad, "Implementation Recommendations to Improve the
Scalability of RSVP-TE Deployments", draft-ietf-teas-rsvp-
te-scaling-rec-03 (work in progress), October 2016.
[I-D.sitaraman-sr-rsvp-coexistence-rec]
Sitaraman, H., Beeram, V., Minei, I., and S. Sivabalan,
"Recommendations for RSVP-TE and Segment Routing LSP co-
existence", draft-sitaraman-sr-rsvp-coexistence-rec-02
(work in progress), February 2017.
[RFC2961] Berger, L., Gan, D., Swallow, G., Pan, P., Tommasi, F.,
and S. Molendini, "RSVP Refresh Overhead Reduction
Extensions", RFC 2961, DOI 10.17487/RFC2961, April 2001,
<http://www.rfc-editor.org/info/rfc2961>.
Sitaraman, et al. Expires September 11, 2017 [Page 13]
Internet-Draft RSVP-TE pop and forward tunnel March 2017
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010,
<http://www.rfc-editor.org/info/rfc5920>.
Authors' Addresses
Harish Sitaraman
Juniper Networks
1133 Innovation Way
Sunnyvale, CA 94089
US
Email: hsitaraman@juniper.net
Vishnu Pavan Beeram
Juniper Networks
10 Technology Park Drive
Westford, MA 01886
US
Email: vbeeram@juniper.net
Tejal Parikh
Verizon
400 International Parkway
Richardson, TX 75081
US
Email: tejal.parikh@verizon.com
Sitaraman, et al. Expires September 11, 2017 [Page 14]