Network Working Group C. Filsfils, Ed.
Internet-Draft S. Previdi, Ed.
Intended status: Standards Track A. Bashandy
Expires: January 4, 2015 Cisco Systems, Inc.
B. Decraene
S. Litkowski
Orange
M. Horneffer
Deutsche Telekom
I. Milojevic
Telekom Srbija
R. Shakir
British Telecom
S. Ytti
TDC Oy
W. Henderickx
Alcatel-Lucent
J. Tantsura
Ericsson
E. Crabbe
Google, Inc.
July 3, 2014
Segment Routing Architecture
draft-filsfils-spring-segment-routing-04
Abstract
Segment Routing (SR) leverages the source routing paradigm. A node
steers a packet through an ordered list of instructions, called
segments. A segment can represent any instruction, topological or
service-based. A segment can have a local semantic to an SR node or
global within an SR domain. SR allows to enforce a flow through any
topological path and service chain while maintaining per-flow state
only at the ingress node to the SR domain.
Segment Routing can be directly applied to the MPLS architecture with
no change on the forwarding plane. A segment is encoded as an MPLS
label. An ordered list of segments is encoded as a stack of labels.
The segment to process is on the top of the stack. Upon completion
of a segment, the related label is popped from the stack.
Segment Routing can be applied to the IPv6 architecture, with a new
type of routing extension header. A segment is encoded as an IPv6
address. An ordered list of segments is encoded as an ordered list
of IPv6 addresses in the routing extension header. The segment to
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process is indicated by a pointer in the routing extension header.
Upon completion of a segment, the pointer is incremented.
Requirements Language
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].
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
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 January 4, 2015.
Copyright Notice
Copyright (c) 2014 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
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Companion Documents . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Link-State IGP Segments . . . . . . . . . . . . . . . . . . . 7
3.1. IGP Segment, IGP SID . . . . . . . . . . . . . . . . . . 7
3.2. IGP-Prefix Segment, Prefix-SID . . . . . . . . . . . . . 7
3.3. IGP-Node Segment, Node-SID . . . . . . . . . . . . . . . 8
3.4. IGP-Anycast Segment, Anycast SID . . . . . . . . . . . . 9
3.5. IGP-Adjacency Segment, Adj-SID . . . . . . . . . . . . . 9
3.5.1. Parallel Adjacencies . . . . . . . . . . . . . . . . 10
3.5.2. LAN Adjacency Segments . . . . . . . . . . . . . . . 11
3.6. Binding Segment . . . . . . . . . . . . . . . . . . . . . 11
3.6.1. Mapping Server . . . . . . . . . . . . . . . . . . . 11
3.6.2. Tunnel Headend . . . . . . . . . . . . . . . . . . . 11
3.6.3. Mirroring Context . . . . . . . . . . . . . . . . . . 12
3.7. Inter-Area Considerations . . . . . . . . . . . . . . . . 12
4. BGP Peering Segments . . . . . . . . . . . . . . . . . . . . 13
5. Multicast . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Manageability Considerations . . . . . . . . . . . . . . . . 14
8. Security Considerations . . . . . . . . . . . . . . . . . . . 14
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
10.1. Normative References . . . . . . . . . . . . . . . . . . 14
10.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
With Segment Routing (SR), a node steers a packet through an ordered
list of instructions, called segments. A segment can represent any
instruction, topological or service-based. A segment can have a
local semantic to an SR node or global within an SR domain. SR
allows to enforce a flow through any path and service chain while
maintaining per-flow state only at the ingress node of the SR domain.
Segment Routing can be directly applied to the MPLS architecture (RFC
3031) with no change on the forwarding plane. A segment is encoded
as an MPLS label. An ordered list of segments is encoded as a stack
of labels. The active segment is on the top of the stack. A
completed segment is popped off the stack. The addition of a segment
is performed with a push.
In the Segment Routing MPLS instantiation, a segment could be of
several types:
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o an IGP segment,
o a BGP Peering segments,
o an LDP LSP segment,
o an RSVP-TE LSP segment,
o a BGP LSP segment.
The first two (IGP and BGP Peering segments) types of segments
defined in this document. The use of the last three types of
segments is illustrated in
[I-D.filsfils-spring-segment-routing-mpls].
Segment Routing can be applied to the IPv6 architecture (RFC2460),
with a new type of routing extension header. A segment is encoded as
an IPv6 address. An ordered list of segments is encoded as an
ordered list of IPv6 addresses in the routing extension header. The
active segment is indicated by a pointer in the routing extension
header. Upon completion of a segment, the pointer is incremented. A
segment can be inserted in the list and the pointer is updated
accordingly.
Numerous use-cases illustrate the benefits of source routing either
for FRR, OAM or Traffic Engineering reasons.
This document defines a set of instructions (called segments) that
are required to fulfill the described use-cases. These segments can
either be used in isolation (one single segment defines the source
route of the packet) or in combination (these segments are part of an
ordered list of segments that define the source route of the packet).
1.1. Companion Documents
This document defines the SR architecture, its routing model, the
IGP-based segments, the BGP-based segments and the service segments.
Use cases are described in
[I-D.filsfils-spring-segment-routing-use-cases],
[I-D.ietf-spring-ipv6-use-cases],
[I-D.ietf-spring-resiliency-use-cases], [I-D.geib-spring-oam-usecase]
and [I-D.kumar-spring-sr-oam-requirement].
Segment Routing for MPLS dataplane is documented in
[I-D.filsfils-spring-segment-routing-mpls].
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Segment Routing for IPv6 dataplane is documented in
[I-D.previdi-6man-segment-routing-header].
IGP protocol extensions for Segment Routing are described in
[I-D.ietf-isis-segment-routing-extensions] and
[I-D.ietf-ospf-segment-routing-extensions]
The FRR solution for SR is documented in
[I-D.francois-segment-routing-ti-lfa].
The PCEP protocol extensions for Segment Routing are defined in
[I-D.sivabalan-pce-segment-routing].
The interaction between SR/MPLS with other MPLS Signaling planes is
documented in [I-D.filsfils-spring-segment-routing-ldp-interop].
2. Terminology
Segment: a segment identifies an instruction
SID: a Segment Identifier
Segment List: ordered list of SID's encoding the topological and
service source route of the packet. It is a stack of labels in the
MPLS architecture. It is an ordered list of IPv6 addresses in the
IPv6 architecture.
Active segment: the segment that MUST be used by the receiving router
to process the packet. It is identified by a pointer in the IPv6
architecture. It is the top label in the MPLS architecture.
PUSH: the insertion of a segment at the head of the Segment list.
NEXT: the active segment is completed, the next segment becomes
active.
CONTINUE: the active segment is not completed and hence remains
active. The CONTINUE instruction is implemented as the SWAP
instruction in the MPLS dataplane.
SR Global Block (SRGB): local property of an SR node. In the MPLS
architecture, SRGB is the set of local labels reserved for global
segments. In the IPv6 architecture, it is the set of locally
relevant IPv6 addresses.
Global Segment: the related instruction is supported by all the SR-
capable nodes in the domain. In the MPLS architecture, a Global
Segment has a globally-unique index. The related local label at a
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given node N is found by adding the globally-unique index to the SRGB
of node N. In the IPv6 architecture, a global segment is a globally-
unique IPv6 address.
Local Segment: the related instruction is supported only by the node
originating it. In the MPLS architecture, this is a local label
outside the SRGB. In the IPv6 architecture, this is a link-local
address.
IGP Segment: the generic name for a segment attached to a piece of
information advertised by a link-state IGP, e.g. an IGP prefix or an
IGP adjacency.
IGP-prefix Segment, Prefix-SID: an IGP-Prefix Segment is an IGP
segment attached to an IGP prefix. An IGP-Prefix Segment is always
global within the SR/IGP domain and identifies an instruction to
forward the packet over the ECMP-aware shortest-path computed by the
IGP to the related prefix. The Prefix-SID is the SID of the IGP-
Prefix Segment.
IGP-Anycast: an IGP-Anycast Segment is an IGP-prefix segment which
does not identify a specific router, but a set of routers. The terms
"Anycast Segment" or "Anycast-SID" are often used as an abbreviation.
IGP-Adjacency: an IGP-Adjacency Segment is an IGP segment attached to
an unidirectional adjacency or a set of unidirectional adjacencies.
By default, an IGP-Adjacency Segment is local (unless explicitly
advertised otherwise) to the node that advertises it.
IGP-Node: an IGP-Node Segment is an IGP-Prefix Segment which
identifies a specific router (e.g. a loopback). The terms "Node
Segment" or Node-SID" are often used as an abbreviation.
SR Tunnel: a list of segments to be pushed on the packets directed on
the tunnel. The list of segments can be specified explicitly or
implicitly via a set of abstract constraints (latency, affinity,
SRLG, ...). In the latter case, a constrained-based path computation
is used to determine the list of segments associated with the tunnel.
The computation can be local or delegated to a PCE server. An SR
tunnel can be configured by the operator, provisioned via netconf or
provisioned via PCEP. An SR tunnel can be used for traffic-
engineering, OAM or FRR reasons.
Segment List Depth: the number of segments of an SR tunnel. The
entity instantiating an SR Tunnel at a node N should be able to
discover the depth insertion capability of the node N. The PCEP
discovery capability is described in
[I-D.sivabalan-pce-segment-routing].
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3. Link-State IGP Segments
Within a link-state IGP domain, an SR-capable IGP node advertises
segments for its attached prefixes and adjacencies. These segments
are called IGP segments or IGP SIDs. They play a key role in Segment
Routing and use-cases
([I-D.filsfils-spring-segment-routing-use-cases]) as they enable the
expression of any topological path throughout the IGP domain. Such a
topological path is either expressed as a single IGP segment or a
list of multiple IGP segments.
3.1. IGP Segment, IGP SID
The terms "IGP Segment" and "IGP SID" are the generic names for a
segment attached to a piece of information advertised by a link-state
IGP, e.g. an IGP prefix or an IGP adjacency.
3.2. IGP-Prefix Segment, Prefix-SID
An IGP-Prefix Segment is an IGP segment attached to an IGP prefix.
An IGP-Prefix Segment is always global within the SR/IGP domain and
identifies the ECMP-aware shortest-path computed by the IGP to the
related prefix. The Prefix-SID is the SID of the IGP-Prefix Segment.
A packet injected anywhere within the SR/IGP domain with an active
Prefix-SID will be forwarded along the shortest-path to that prefix.
The IGP signaling extension for IGP-Prefix segment includes the
P-Flag. A Node N advertising a Prefix-SID SID-R for its attached
prefix R resets the P-Flag to allow its connected neighbors to
perform the NEXT operation while processing SID-R. This behavior is
equivalent to Penultimate Hop Popping in MPLS. When set, the
neighbors of N must perform the CONTINUE operation while processing
SID-R.
While SR allows to attach a local segment to an IGP prefix (using the
L-Flag), we specifically assume that when the terms "IGP-Prefix
Segment" and "Prefix-SID" are used, the segment is global (the SID is
allocated from the SRGB). This is consistent with
[I-D.filsfils-spring-segment-routing-use-cases] as all the described
use-cases require global segments attached to IGP prefixes.
A single Prefix-SID is allocated to an IGP Prefix in a topology.
In the context of multiple topologies, multiple Prefix-SID's MAY be
allocated to the same IGP Prefix (e.g.: using the "algorithm" field
in the IGP advertisement as described in
[I-D.ietf-isis-segment-routing-extensions] and
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[I-D.ietf-ospf-segment-routing-extensions]). However, each prefix-
SID MUST be associated with only one topology. In other words: a
prefix, within a topology, MUST have only a single Prefix-SID.
A Prefix-SID is allocated from the SRGB according to a process
similar to IP address allocation. Typically the Prefix-SID is
allocated by policy by the operator (or NMS) and the SID very rarely
changes.
The allocation process MUST NOT allocate the same Prefix-SID to
different IP prefixes.
If a node learns a Prefix-SID having a value that falls outside the
locally configured SRGB range, then the node MUST NOT use the Prefix-
SID and SHOULD issue an error log warning for misconfiguration.
The required IGP protocol extensions are defined in
[I-D.ietf-isis-segment-routing-extensions]and
[I-D.ietf-ospf-segment-routing-extensions].
A node N attaching a Prefix-SID SID-R to its attached prefix R MUST
maintain the following FIB entry:
Incoming Active Segment: SID-R
Ingress Operation: NEXT
Egress interface: NULL
A remote node M MUST maintain the following FIB entry for any learned
Prefix-SID SID-R attached to IP prefix R:
Incoming Active Segment: SID-R
Ingress Operation:
If the next-hop of R is the originator of R
and instructed to remove the active segment: NEXT
Else: CONTINUE
Egress interface: the interface towards the next-hop along
the shortest-path to prefix R.
3.3. IGP-Node Segment, Node-SID
An IGP-Node Segment is a an IGP-Prefix Segment which identifies a
specific router (e.g. a loopback). The N flag is set. The terms
"Node Segment" or "Node-SID" are often used as an abbreviation.
A "Node Segment" or "Node-SID" is fundamental to SR. From anywhere
in the network, it enforces the ECMP-aware shortest- path forwarding
of the packet towards the related node as explained in
[I-D.filsfils-spring-segment-routing-use-cases].
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An IGP-Node-SID MUST NOT be associated with a prefix that is owned or
advertised by more than one router within the same routing domain.
3.4. IGP-Anycast Segment, Anycast SID
An IGP-Anycast Segment is an IGP-prefix segment which does not
identify a specific router, but a set of routers. The terms "Anycast
Segment" or "Anycast-SID" are often used as an abbreviation.
An "Anycast Segment" or "Anycast SID" enforces the ECMP-aware
shortest-path forwarding towards the closest node of the anycast set.
This is useful to express macro-engineering policies or protection
mechanisms as described in
[I-D.filsfils-spring-segment-routing-use-cases].
The Anycast SID MUST be advertised with the N-flag unset.
3.5. IGP-Adjacency Segment, Adj-SID
An IGP-Adjacency Segment is an IGP segment attached to a
unidirectional adjacency or a set of unidirectional adjacencies. By
default, an IGP-Adjacency Segment is local to the node which
advertises it. However, an Adjacency Segment can be global if
advertised by the IGP as such. The SID of the IGP-Adjacency Segment
is called the Adj-SID.
The adjacency is formed by the local node (i.e., the node advertising
the adjacency in the IGP) and the remote node (i.e., the other end of
the adjacency). The local node MUST be an IGP node. The remote node
MAY be an adjacent IGP neighbor) or a non-adjacent neighbor (e.g.: a
Forwarding Adjacency, [RFC4206]).
A packet injected anywhere within the SR domain with a segment list
{SN, SNL}, where SN is the Node-SID of node N and SNL is an Adj-SID
attached by node N to its adjacency over link L, will be forwarded
along the shortest-path to N and then be switched by N, without any
IP shortest-path consideration, towards link L. If the Adj-SID
identifies a set of adjacencies, then the node N load- balances the
traffic among the various members of the set.
Similarly, when using a global Adj-SID, a packet injected anywhere
within the SR domain with a segment list {SNL}, where SNL is a global
Adj-SID attached by node N to its adjacency over link L, will be
forwarded along the shortest-path to N and then be switched by N,
without any IP shortest-path consideration, towards link L. If the
Adj-SID identifies a set of adjacencies, then the node N load-
balances the traffic among the various members of the set. The use
of global Adj-SID allows to reduce the size of the segment list when
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expressing a path at the cost of additional state (i.e.: the global
Adj-SID will be inserted by all routers within the area in their
forwarding table).
An "IGP Adjacency Segment" or "Adj-SID" enforces the switching of the
packet from a node towards a defined interface or set of interfaces.
This is key to theoretically prove that any path can be expressed as
a list of segments as explained in
[I-D.filsfils-spring-segment-routing-use-cases].
The encodings of the Adj-SID include the B-flag. When set, the Adj-
SID benefits from a local protection.
The encodings of the Adj-SID include the L-flag. When set, the Adj-
SID has local significance. By default the L-flag is set.
A node SHOULD allocate one Adj-SIDs for each of its adjacencies.
A node MAY allocate multiple Adj-SIDs to the same adjacency. An
example is where the adjacency is established over a bundle
interface. Each bundle member MAY have its own Adj-SID.
A node MAY allocate the same Adj-SID to multiple adjacencies.
Adjacency suppression MUST NOT be performed by the IGP.
A node MUST install a FIB entry for any Adj-SID of value V attached
to data-link L:
Incoming Active Segment: V
Operation: NEXT
Egress Interface: L
The Adj-SID implies, from the router advertising it, the forwarding
of the packet through the adjacency identified by the Adj-SID,
regardless its IGP/SPF cost. In other words, the use of Adjacency
Segments overrides the routing decision made by SPF algorithm.
3.5.1. Parallel Adjacencies
Adj-SIDs can be used in order to represent a set of parallel
interfaces between two adjacent routers.
A node MUST install a FIB entry for any locally originated Adjacency
Segment (Adj-SID) of value W attached to a set of link B with:
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Incoming Active Segment: W
Ingress Operation: NEXT
Egress interface: loadbalance between any data-link within set B
3.5.2. LAN Adjacency Segments
In LAN subnetworks, link-state protocols define the concept of
Designated Router (DR, in OSPF) or Designated Intermediate System
(DIS, in IS-IS) that conduct flooding in broadcast subnetworks and
that describe the LAN topology in a special routing update (OSPF
Type2 LSA or IS-IS Pseudonode LSP).
The difficulty with LANs is that each router only advertises its
connectivity to the DR/DIS and not to each other individual nodes in
the LAN. Therefore, additional protocol mechanisms (IS-IS and OSPF)
are necessary in order for each router in the LAN to advertise an
Adj-SID associated to each neighbor in the LAN. These extensions are
defined in [I-D.ietf-isis-segment-routing-extensions] and
[I-D.ietf-ospf-segment-routing-extensions].
3.6. Binding Segment
3.6.1. Mapping Server
A Remote-Binding SID S advertised by the mapping server M for remote
prefix R attached to non-SR-capable node N signals the same
information as if N had advertised S as a Prefix-SID. Further
details are described in the SR/LDP interworking procedures
([I-D.filsfils-spring-segment-routing-ldp-interop].
The segment allocation and SRDB Maintenance rules are the same as
those defined for Prefix-SID.
3.6.2. Tunnel Headend
The segment allocation and SRDB Maintenance rules are the same as
those defined for Adj-SID. A tunnel attached to a head-end H acts as
an adjacency attached to H.
Note: an alternative would consist in representing tunnels as
forwarding-adjacencies ( [RFC4206]). The Remote-Binding SID is
preferred as it allows to advertise the presence of a tunnel without
influencing the LSDB and the SPF computation.
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3.6.3. Mirroring Context
TBD.
3.7. Inter-Area Considerations
In the following example diagram we assume an IGP deployed using
areas and where SR has been deployed.
! !
! !
B------C-----F----G-----K
/ | | |
S---A/ | | |
\ | | |
\D------I----------J-----L----Z (192.0.2.1/32, Node-SID: 150)
! !
Area-1 ! Backbone ! Area 2
! area !
Figure 1: Inter-Area Topology Example
In area 2, node Z allocates Node-SID 150 to his local prefix
192.0.2.1/32. ABRs G and J will propagate the prefix into the
backbone area by creating a new instance of the prefix according to
normal inter-area/level IGP propagation rules.
Nodes C and I will apply the same behavior when leaking prefixes from
the backbone area down to area 1. Therefore, node S will see prefix
192.0.2.1/32 with Prefix-SID 150 and advertised by nodes C and I.
It therefore results that a Prefix-SID remains attached to its
related IGP Prefix through the inter-area process.
When node S sends traffic to 192.0.2.1/32, it pushes Node-SID(150) as
active segment and forward it to A.
When packet arrives at ABR I (or C), the ABR forwards the packet
according to the active segment (Node-SID(150)). Forwarding
continues across area borders, using the same Node-SID(150), until
the packet reaches its destination.
When an ABR propagates a prefix from one area to another it MUST set
the R-Flag.
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4. BGP Peering Segments
In the context of BGP Egress Peer Engineering (EPE), as described in
[draft-filsfils-spring-segment-routing-central-epe], an EPE enabled
Egress PE node MAY advertise segments corresponding to its attached
peers. These segments are called BGP peering segments or BGP Peering
SIDs. They enable the expression of source-routed inter-domain
paths.
An ingress border router of an AS may compose a list of segments to
steer a flow along a selected path within the AS, towards a selected
egress border router C of the AS and through a specific peer. At
minimum, a BGP Peering Engineering policy applied at an ingress PE
involves two segments: the Node SID of the chosen egress PE and then
the BGP Peering Segment for the chosen egress PE peer or peering
interface.
Hereafter, we will define three types of BGP peering segments/SID's:
PeerNodeSID, PeerAdjSID and PeerSetSID.
o PeerNode SID. A BGP PeerNode segment/SID is a local segment. At
the BGP node advertising it, its semantics is:
* SR header operation: NEXT.
* Next-Hop: the connected peering node to which the segment is
related.
o PeerAdj SID: A BGP PeerAdj segment/SID is a local segment. At the
BGP node advertising it, its semantics is:
* SR header operation: NEXT.
* Next-Hop: the peer connected through the interface to which the
segment is related.
o PeerSet SID. A BGP PeerSet segment/SID is a local segment. At
the BGP node advertising it, its semantics is:
* SR header operation: NEXT.
* Next-Hop: loadbalance across any connected interface to any
peer in the related group.
A peer set could be all the connected peers from the same AS or a
subset of these. A group could also span across AS. The group
definition is a policy set by the operator.
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The BGP extensions necessary in order to signal these BGP peering
segments will be defined in a separate document.
5. Multicast
Segment Routing is defined for unicast. The application of the
source-route concept to Multicast is not in the scope of this
document.
6. IANA Considerations
TBD
7. Manageability Considerations
TBD
8. Security Considerations
TBD
9. Acknowledgements
We would like to thank Dave Ward, Dan Frost, Stewart Bryant, Pierre
Francois, Thomas Telkamp, Les Ginsberg, Ruediger Geib and Hannes
Gredler for their contribution to the content of this document.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4206] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP)
Hierarchy with Generalized Multi-Protocol Label Switching
(GMPLS) Traffic Engineering (TE)", RFC 4206, October 2005.
10.2. Informative References
[I-D.filsfils-spring-segment-routing-ldp-interop]
Filsfils, C., Previdi, S., Bashandy, A., Decraene, B.,
Litkowski, S., Horneffer, M., Milojevic, I., Shakir, R.,
Ytti, S., Henderickx, W., Tantsura, J., and E. Crabbe,
"Segment Routing interoperability with LDP", draft-
filsfils-spring-segment-routing-ldp-interop-01 (work in
progress), April 2014.
Filsfils, et al. Expires January 4, 2015 [Page 14]
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[I-D.filsfils-spring-segment-routing-mpls]
Filsfils, C., Previdi, S., Bashandy, A., Decraene, B.,
Litkowski, S., Horneffer, M., Milojevic, I., Shakir, R.,
Ytti, S., Henderickx, W., Tantsura, J., and E. Crabbe,
"Segment Routing with MPLS data plane", draft-filsfils-
spring-segment-routing-mpls-02 (work in progress), June
2014.
[I-D.filsfils-spring-segment-routing-use-cases]
Filsfils, C., Francois, P., Previdi, S., Decraene, B.,
Litkowski, S., Horneffer, M., Milojevic, I., Shakir, R.,
Ytti, S., Henderickx, W., Tantsura, J., Kini, S., and E.
Crabbe, "Segment Routing Use Cases", draft-filsfils-
spring-segment-routing-use-cases-00 (work in progress),
March 2014.
[I-D.francois-segment-routing-ti-lfa]
Francois, P., Filsfils, C., Bashandy, A., and B. Decraene,
"Topology Independent Fast Reroute using Segment Routing",
draft-francois-segment-routing-ti-lfa-00 (work in
progress), November 2013.
[I-D.geib-spring-oam-usecase]
Geib, R. and C. Filsfils, "Use case for a scalable and
topology aware MPLS data plane monitoring system", draft-
geib-spring-oam-usecase-01 (work in progress), February
2014.
[I-D.ietf-isis-segment-routing-extensions]
Previdi, S., Filsfils, C., Bashandy, A., Gredler, H.,
Litkowski, S., Decraene, B., and J. Tantsura, "IS-IS
Extensions for Segment Routing", draft-ietf-isis-segment-
routing-extensions-02 (work in progress), June 2014.
[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-00 (work in progress), June 2014.
[I-D.ietf-spring-ipv6-use-cases]
Brzozowski, J., Leddy, J., Leung, I., Previdi, S.,
Townsley, W., Martin, C., Filsfils, C., and R. Maglione,
"IPv6 SPRING Use Cases", draft-ietf-spring-ipv6-use-
cases-00 (work in progress), May 2014.
Filsfils, et al. Expires January 4, 2015 [Page 15]
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[I-D.ietf-spring-resiliency-use-cases]
Francois, P., Filsfils, C., Decraene, B., and R. Shakir,
"Use-cases for Resiliency in SPRING", draft-ietf-spring-
resiliency-use-cases-00 (work in progress), May 2014.
[I-D.kumar-spring-sr-oam-requirement]
Kumar, N., Pignataro, C., Akiya, N., Geib, R., and G.
Mirsky, "OAM Requirements for Segment Routing Network",
draft-kumar-spring-sr-oam-requirement-00 (work in
progress), February 2014.
[]
Previdi, S., Filsfils, C., Field, B., and I. Leung, "IPv6
Segment Routing Header (SRH)", draft-previdi-6man-segment-
routing-header-01 (work in progress), June 2014.
[I-D.sivabalan-pce-segment-routing]
Sivabalan, S., Medved, J., Filsfils, C., Crabbe, E., and
R. Raszuk, "PCEP Extensions for Segment Routing", draft-
sivabalan-pce-segment-routing-02 (work in progress),
October 2013.
[draft-filsfils-spring-segment-routing-central-epe]
Filsfils, C. and S. Previdi, "Segment Routing Centralized
Egress Peer Engineering", May 2013.
Authors' Addresses
Clarence Filsfils (editor)
Cisco Systems, Inc.
Brussels
BE
Email: cfilsfil@cisco.com
Stefano Previdi (editor)
Cisco Systems, Inc.
Via Del Serafico, 200
Rome 00142
Italy
Email: sprevidi@cisco.com
Filsfils, et al. Expires January 4, 2015 [Page 16]
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Ahmed Bashandy
Cisco Systems, Inc.
170, West Tasman Drive
San Jose, CA 95134
US
Email: bashandy@cisco.com
Bruno Decraene
Orange
FR
Email: bruno.decraene@orange.com
Stephane Litkowski
Orange
FR
Email: stephane.litkowski@orange.com
Martin Horneffer
Deutsche Telekom
Hammer Str. 216-226
Muenster 48153
DE
Email: Martin.Horneffer@telekom.de
Igor Milojevic
Telekom Srbija
Takovska 2
Belgrade
RS
Email: igormilojevic@telekom.rs
Rob Shakir
British Telecom
London
UK
Email: rob.shakir@bt.com
Filsfils, et al. Expires January 4, 2015 [Page 17]
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Saku Ytti
TDC Oy
Mechelininkatu 1a
TDC 00094
FI
Email: saku@ytti.fi
Wim Henderickx
Alcatel-Lucent
Copernicuslaan 50
Antwerp 2018
BE
Email: wim.henderickx@alcatel-lucent.com
Jeff Tantsura
Ericsson
300 Holger Way
San Jose, CA 95134
US
Email: Jeff.Tantsura@ericsson.com
Edward Crabbe
Google, Inc.
1600 Amphitheatre Parkway
Mountain View, CA 94043
US
Email: edc@google.com
Filsfils, et al. Expires January 4, 2015 [Page 18]
