wdiff draft-vandevelde-idr-flowspec-path-redirect-02.txt draft-vandevelde-idr-flowspec-path-redirect-03.txt

IDR Working Group G. Van de Velde, Ed.
Internet-Draft W. Henderickx
Intended status: Standards Track Alcatel-Lucent Nokia
Expires: September 18, 2016 January 9, 2017 K. Patel
A. Sreekantiah
Cisco Systems
March 17,
Z. Li
S. Zhuang
N. Wu
Huawei Technologies
July 8, 2016

Flowspec Indirection-id Redirect
draft-vandevelde-idr-flowspec-path-redirect-02
draft-vandevelde-idr-flowspec-path-redirect-03

Abstract

Flow-spec

Flowspec is an extension to BGP that allows for the dissemination of
traffic flow specification rules. This has many possible
applications but the primary one for many network operators is the
distribution of traffic filtering actions for DDoS mitigation. The
flow-spec standard RFC5575 [2] defines a redirect-to-VRF action for
policy-based forwarding but this mechanism is not always sufficient,
particular
particularly if the redirected traffic needs to be steered into an
engineered path or into a service plane.

This document defines a new redirect-to-INDIRECTION_ID (32-bit or
128-bit) flow-spec extended community known as redirect-to-
indirection-id (32-bit) flowspec action to provide advanced
redirection
capabilities. capabilities on flowspec clients. When activated, the
flowspec Indirection-id extended community is used by a flowspec client to
identify find the
correct next-hop redirect information entry within a router locallized
Indirection-id localised indirection-id mapping
table. This

The functionality present in this draft allows a flowspec network controller
to signal
redirection towards a next-hop IP address, a shortest path tunnel, a
traffic engineered tunnel or a next-next-hop engineered tunnel
interface. decouple flowspec functionality from the creation and maintainance
of the network's service plane itself including the setup of tunnels
and other service constructs that could be managed by other network
devices.

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 [1].

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 September 18, 2016. January 9, 2017.

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
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 3
2. INDIRECTION_ID indirection-id and INDIRECTION_ID Table indirection-id table . . . . . . . . . . . 3
3. Use Case Scenarios . . . . . . . . . . . . . . . . . . . . . 4
3.1. Redirection shortest Path tunnel . . . . . . . . . . . . 4
3.2. Redirection to path-engineered tunnels . . . . . . . . . 4
3.3. Redirection to Next-next-hop tunnels . . . . . . . . . . 5
4. Redirect to INDIRECTION-ID Communities indirection-id Community . . . . . . . . . . . . 6
5. Redirect using locallized INDIRECTION_ID Router Mapping localised indirection-id mapping table . . . 7 . 8
6. Validation Procedures . . . . . . . . . . . . . . . . . . . . 8
7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 9
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 9
10.1. Normative References . . . . . . . . . . . . . . . . . . 9 10
10.2. Informative References . . . . . . . . . . . . . . . . . 9 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 10

1. Introduction

Flow-spec

Flowspec RFC5575 [2] is an extension to BGP that allows for the
dissemination of traffic flow specification rules. This has many
possible applications but applications, however the primary one for many network
operators is the distribution of traffic filtering actions for DDoS
mitigation.

Every flow-spec flowspec policy route is effectively a rule, consisting of a
matching part (encoded in the NLRI field) and an action part (encoded
in one or more BGP extended community). communities). The flow-spec standard
RFC5575 [2] defines widely-used filter actions such as discard and
rate limit; it also defines a redirect-to-VRF action for policy-based
forwarding. Using the redirect-to-VRF action for redirecting to steer traffic
towards an alternate destination is useful for DDoS mitigation but
using this technology can be cumbersome when there is need to redirect steer
the traffic onto an engineered traffic path.

This draft proposes a new redirect-to-Indirection-id flow-spec redirect-to-indirection-id flowspec action
facilitating an anchor point for policy-based forwarding onto an
engineered path or into a service plane. The router flowspec client
consuming and utilizing the new flowspec rule makes indirection-id extended-
community finds the redirection information within a local localised
indirection-id mapping between table. The localised mapping table is a table
construct providing at one side the
flowspec signalled redirect Indirection-id table key and locally available
redirection information referenced by at the Indirection-id. This
locally available redirection information is derived from out-of-band
programming or signalling. other side
next-hop information. The table key consists out the combination of
indirection-id type and indirection-id 32-bit value.

The redirect-to-Indirection-id redirect-to-indirection-id flowspec action is encoded in a newly
defined BGP extended Indirection_ID community.

The construction In addition, the type of redirection
can be configured as an extended community indirection-id type field.

This draft defines the Indirection-id redirect table indirection-id extended-community and the
technology used
wellknown indirection-id types. The specific solution to create an engineered path construct
the localised indirection-id mapping table are out-of-scope of this
document.

2. INDIRECTION_ID indirection-id and INDIRECTION_ID Table indirection-id table

An INDIRECTION_ID indirection-id is an abstract number (32-bit or 128-bit value) used as
identifier for a localised redirection indirection decision. e.g. When The indirection-id
will allow a
BGP flowspec controller intends client to redirect traffic into a flow using te redirect-
to-INDIRECTION_ID action then it has the ability to redirect the flow
to service plane
or onto an engineered traffic path. e.g. When a destination abstracted as the INDIRECTION_ID. The device
receiving the BGP flowspec rule will use
controller signals a flowspec client the INDIRECTION_ID to
identify indirection-id extended
community, then the next-hop and flowspec client uses the relevant tunnel encapsulations that
need indirection-id to be pushed by make a localised
recursive lookup using to retrieve next-hop information
located within the INDIRECTION_ID found in a
localised indirection mapping table.

The INDIRECTION_ID Table indirection-id table is a router localised table. The
indirection-id table
content is constructed out of INDIRECTION_IDs and corresponding
redirect information which may be of rescursive or non-recursive
nature. When the redirect information table keys mapped to
flowspec client localised redirection information. The table key is non-recursive, then
created by the
represented information MUST be sufficient to identify combination of the local
egress interface indirection-id type and the corresponding required encapsulations.
However, if the information is recursive, then
indirection-id 32-bit value. Each entry in the represented
information MUST be indirection-table key
maps to sufficient information (parameters regarding encapsulation,
interface, QoS, etc...) to identify the local egress interface
and corresponding encapsulations using additional recursions. successfully redirect traffic.

3. Use Case Scenarios

This section describes use-case scenarios when deploying redirect-to-
INDIRECTION_ID.
indirection-id.

3.1. Redirection shortest Path tunnel

A first use-case is allowing a BGP Flowspec controller to send a
single flowspec policy message (redirect-to-INDIRECTION_ID#1) route (i.e. flowspec_route#1) to many BGP
flowspec consuming routers. clients. This message is instructing flowspec route signals the Flowspec
recipient routers clients
to redirect traffic onto a tunnel to towards a single IP destination
address.

For this first use-case scenario, each the flowspec recipient router has a
tunnel configured following client receives from
the shortest path towards a tunnel IP
destination address. Each tunnel can have its own unique
encapsulation associated. Each tunnel is associated with an
INDIRECTION_ID, and for this example it is on all recipient routers
INDIRECTION_ID#1. Both manual and orchestrated tunnel provisioning
is supported, however for large scale deployment automation is
advisable.

When using this setup, a BGP flowspec controller can send a single
BGP Flowspec NLRI with redirect-to-INDIRECTION_ID#1. This BGP
Flowspec NLRI is received by all recipient routers. Each of flowspec route (i.e. flowspec_route#1)
including the
recipient routers performs a locallised recursive lookup for
INDIRECTION_ID#1 in redirect-to-indirection-id extended community. The
redirect-to-indirection-id extended community contains the INDIRECTION_ID Table and identifies key
(indirection-id type + indirection-id 32-bit value) to select the
corresponding locallised next-hop information from the flowpsec client localised
indirection-id table. The resulting next-hop information for this
use-case is a remote tunnel redirect information. This
locallised end-point IP address with accordingly
sufficient tunnel encapsulation information is now used to forward the packet
accordingly.

For redirect traffic
matching to shortest path tunnel it is required that the Flowspec policy towards a tunnel, each potentially using
its own unique tunnel encapsulation.
MUST be operational and allow packets to be exchanged between tunnel
head- and tail-end.

3.2. Redirection to path-engineered tunnels

A second use-case is allowing a BGP Flowspec controller send

For a single
flowspec policy message (redirect-to-INDIRECTION_ID#2) to many BGP
flowspec consuming routers. This message second use-case, it is instructing expected that the Flowspec
recipient routers to flowspec client
redirect traffic matches the flowspec rule, onto a path engineered
tunnel.

For this use-case scenario, each flowspec recipient router has a The path engineered tunnel configured. on the flowspec client SHOULD be
created by out-of-band mechanisms. Each tunnel can have its own unique
encapsulation and engineered path associated. Each engineered tunnel is
associated with an INDIRECTION_ID, and
deployed for this example it is on all
recipient routers INDIRECTION_ID#2. Both manual flowspec redirection, has a unque key as an identifier.
consequently, the key (=indirection-id type and orchestrated indirection-id 32-bit
value) uniquely identifies a single path engineered tunnel provisioning is supported, however for large scale deployment
automation on the
flowspec client. The localised indirection-id mapping table is advisable.

A first example using the
collection of all keys corresponding all path engineered tunnels on
the flowspec client.

For this setup, is when a BGP second use-case scenario, the flowspec controller sends a single BGP Flowspec NLRI with redirect-to-INDIRECTION_ID#2.
This BGP Flowspec NLRI is received by all recipient routers. Each of
flowspec route (i.e. flowspec_route#2) to the recipient routers performs a locallised recursive lookup for
INDIRECTION_ID#2 in flowspec clients. The
flowspec clients, respectively receive the flowspec route. The
redirect-to-indirection-id extended community contains the INDIRECTION_ID Table and identifies key
(indirection type + indirection-id 32-bit value) to select the
corresponding locallised next-hop information from the flowpsec client localised
indirection-id table. The resulting next-hop information for this
use-case is path engineered tunnel redirect information. This
locallised information and has sufficient
tunnel encapsulation information is now used to redirect traffic
matching forward the Flowspec policy towards a path engineered tunnel. packet according the
expectations of the flowspec controller.

A second concrete example of this use-case can be found in segment routed
networks where path engineered tunnels can be setup by means of a
controller signaling explicit paths to peering routers. In such a
case, the
INDIRECTION_ID indirection-id references to a Segment Routing Binding SID. SID,
while the indirection-id type references the Bindging SID semantic.
The Binding SID is a segment identifier value (as per segment routing
definitions in [I-D.draft-ietf-spring-segment-routing] [6]) used to
associate with a an explicit path and can be setup by a controller
using BGP as specified in [I-D.sreekantiah-idr-segment-routing-te]
[5] or using PCE as detailed in draft-ietf-pce-segment-routing [7].
When a BGP speaker receives a flow-spec route with a 'redirect to
Binding SID' extended community, it installs a traffic filtering rule
that matches the packets described by the NLRI field and redirects
them to the explicit path associated with the Binding SID. The
explicit path is specified as a set/stack of segment identifiers as
detailed in the previous documents. The stack of segment identifiers
is now imposed on packets matching the flow-spec rule to perform
redirection as per the explicit path setup prior. The encoding of
the Binding SID value is specified in section 4, with the indirection
indirection-id field now encoding the associated value for the
binding SID.

3.3. Redirection to Next-next-hop tunnels

A Third use-case is allowing when a BGP Flowspec controller send sends a single
flowspec policy message (redirect-to-INDIRECTION_ID#3) route to many BGP flowpsec clients to signal redirection
towards next-next-hop tunnels. In this use-case The flowspec consuming routers. This message rule is
instructing the Flowspec
recipient routers client to redirect traffic onto a shortest or engineered
path to using a tunnel end-point and onwards to the next-hop-interface on
this end-point. This type sequence
of tunnel is used for example for Segment
Routing Central Egress Path Engineering [4].

For this use-case scenario, each flowspec recipient router constructs
redirect information using two tunnel components. indirection-id extended communities. The first
component sequence of indirection-
ids is managed using Tunnel IDs (TID). i.e. a shortest or engineered path towards a network egress
router. The second component is the interface used on this network
egress router to which the redirected traffic needs to classic example would
be steered
upon. The combination of these two components allows steering DDoS mitigation towards the next-hop of the egress router, allowing for example the Segment Routing Central Egress Path
Engineering using BGP Flowspec [4].

The redirection towards a next-next-hop tunnel can be done by using
either a single INDIRECTION_ID representing the combined path to the
egress router and steering the To steer DDoS traffic to the egress interface, or by
using individual INDIRECTION_IDs each representing a tunnel component
(One INDIRECTION_ID value to identify the path towards the egress
router and another INDIRECTION_ID value to identify the egress
interface on this egress router towards the next-next-hop). When
using individual INDIRECTION_IDs it is required to use INDIRECTION_ID
community Tunnel IDs (TID) each identifying a component of the
complete redirect path attached to the NLRI.

i.e. when using next-next-hop tunnels, peer
engineering paths, a BGP flowspec controller can
send first indirection-id will steer traffic onto a single BGP Flowspec NLRI with redirect-to-INDIRECTION_ID#3.
This BGP Flowspec NLRI
tunnel to an egress router, while a second indirection-id is received by all recipient routers. Each of used
steer the recipient routers performs traffic at this egress router onto a locallised recursive lookup particular interface
or towards a peer. The flowspec client will for
INDIRECTION_ID#3 in the INDIRECTION_ID Table and identifies the
corresponding locallised tunnel redirect information (=path this use-case
dynamically append all segment routing segments to steer the
egress router and DDoS
traffic through the next-hop egress interface on EPE path.

To achieve this router).
Traffic matching type of redirection to next-next-hop tunnels,
multiple indirection-ids, each using a unique Tunnel ID are imposed
upon a the flowspec policy is redirected towards rule. The Tunnel ID will allow the
recursively found redirection information.
flowspec client to sequence the indirection-ids for correct next-
next-hop tunnel constructs.

4. Redirect to INDIRECTION-ID Communities indirection-id Community

This document defines a new BGP extended community known as a
Redirect-to-indirection-id extended community. The This extended
communities have a type indicating they are transitive and IPv4-
address-specific or IPv6-address-specific, depending on whether the
INDIRECTION_ID
community is 32-bit or 128-bit. The sub-type value [to be
assigned by IANA] indicates that the global administrator and local
administrator fields encode a flow-spec 'redirect to INDIRECTION_ID'
action. In the new transitive extended community with the 4-byte or 16-byte global
administrator field encodes the 32-bit or 128-bit INDIRECTION_ID's
providing the INDIRECTION_ID to allow a local to Type and
the router mapping
reference Sub-Type field to an engineered Path. be assigned by IANA. The 2-byte local administrator
field format of this
extended community is formatted as shown show in Figure 1.

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 | Reserved |B|TID|C|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Sub-Type | Flags(1 octet)| Indirection ID|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Generalized indirection_id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 1

In the local administrator field

The meaning of the extended community fields are as follows:

Type: 1 octet to be assigned by IANA.

Sub-Type: 1 octet to be assigned by IANA.

Flags: 1 octet field. Following Flags are defined.

0 1
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
| RES | TID |C|
+-+-+-+-+-+-+-+-+

Figure 2

The least-significant Flag bit is defined as the 'C' (or copy) bit.
When the 'C' bit is set the redirection applies to copies of the
matching packets and not to the original traffic stream.

The 'TID' field identifies a 2 4 bit Table-id field. This field is
used to provide the router consuming the flowspec rule client an indication how and where to use the INDIRECTION_ID when redirecting traffic.

Bit 2 is defined to be the 'B' (Binding) bit. When the 'B' bit is
set,
sequence the received indirection-ids to redirecting traffic. TID
value encoded in the global administrator 0 indicates that Table-id field is a Binding
Segment Identifier value the use of which is detailed in section 3.2. NOT set and SHOULD be
ignored.

All bits other than the 'C', 'TID' 'C' and 'B' 'TID' bits in the local
administrator field MUST be set to 0 by the
originating BGP speaker and ignored by receiving BGP speakers.

Indirection ID: 1 octet value. This draft defines following
indirection_id Types:

0 - Localised ID

1 - Node ID

2 - Agency ID

3 - AS (Autonomous System) ID

4 - Anycast ID

5 - Multicast ID

6 - Tunnel ID (Tunnel Binding ID )

7 - VPN ID

8 - OAM ID

9 - ECMP (Equal Cost Multi-Path) ID

10 - QoS ID

11 - Bandwidth-Guarantee ID
12 - Security ID

13 - Multi-Topology ID

5. Redirect using locallized INDIRECTION_ID Router Mapping localised indirection-id mapping table

When a BGP speaker receives a flow-spec flowspec policy route with a 'redirect
to
INDIRECTION_ID' indirection-id' extended community and this route represents the
one and only best path, path or an equal cost multipath, it installs a
traffic filtering rule that matches the packets described by the NLRI
field and redirects them (C=0) or copies them (C=1) towards the INDIRECTION_ID
indirection-id local recursed Path.
The BGP speaker is expected to do a local INDIRECTION_ID Table lookup
to identify path. To construct the redirection information.

The router local INDIRECTION_ID table contains a list of
INDIRECTION_ID's each mapped to redirect information. The redirect
information can be non-recursive (i.e. there is only one option
available in the INDIRECTION_ID Table) or recursive (i.e. L3 VPN, L2
VPN, a pre-programmed routing topology, etc... ).

o When the redirect information is non-recursive then the packet is
redirected based upon the information found in the Table.

o In case of a next-hop tunnel, the traffic matching recursed
path, the flowspec
rule is redirected to the next-hop tunnel. This tunnel could be
instantiated through various means (i.e. manual configuration,
PCEP, RSVP-TE, WAN Controller, Segment Routing, etc...).

o In case of redirection to client does a local next-hop interface, the traffic
matching the flowspec rule is redirected to the local next-hop
interface.

o In case the INDIRECTION_ID Table indirection-id mapping table
lookup results in redirect
information identifying an additional layer using the key comprised of recursion, then
this will trigger the flow indirection-id 32-bit value and
indirection-id type to be redirected based upon an
additional routing lookup within retrieve the realm of the additional layer
of recursion. correct redirection information.

6. Validation Procedures

The validation check described in RFC5575 [2] and revised in [3]
SHOULD be applied by default to received flow-spec routes with a
'redirect to INDIRECTION_ID' indirection-id' extended community. This means that a
flow-spec route with a destination prefix subcomponent SHOULD NOT be
accepted from an EBGP peer unless that peer also advertised the best
path for the matching unicast route.

It is possible from a semenatics perspective to have multiple
redirect actions defined within a single flowspec rule. When a BGP
flowspec NLRI has a 'redirect to INDIRECTION_ID' indirection-id' extended community
attached resulting in valid redirection then it MUST take priority
above all other redirect actions emposed. However, if the 'redirect
to INDIRECTION_ID' indirection-id' does not result in a valid redirection, then the
flowspec rule must be processed as if the 'redirect to
INDIRECTION_ID' indirection-
id' community was not attached to the flowspec route and MUST provide
an indication within the BGP routing table that the respective
'redirect to INDIRECTION_ID' indirection-id' resulted in an invalid redirection
action.

7. Security Considerations

A system using 'redirect-to-INDIRECTION_ID' 'redirect-to-indirection-id' extended community can
cause during the redirect mitigation of a DDoS attack result in an
overflow of traffic being received by the mitigation infrastructure.

8. Acknowledgements

This document received valuable comments and input from IDR working
group including Adam Simpson, Mustapha Aissaoui, Jan Mertens, Robert
Raszuk, Jeff Haas, Susan Hares and Lucy Yong

9. IANA Considerations

This document requests a new type and sub-type for the Redirect to
indirection-id Extended community from the "Transitive IPv4-
Address-Specific" extended community Extended
community" registry. The sub-type Type name shall be "Redirect to
indirection-id Extended Community" and the Sub-type name shall be
'Flow-spec Redirect to 32-bit Path-id'.

This

In addition, this document requests IANA to create a new sub-type from the "Transitive IPv6-
Address-Specific" extended community registry. The sub-type name
shall be 'Flow-spec registry for
Redirect to 128-bit Path-id'. indirection-id Extended Community INDIRECTION-IDs as
follows:

Under "Transitive Extended Community:"

Registry: "Redirect Extended Community indirection_id"

Reference: [RFC-To-Be]

Registration Procedure(s): First Come, First Served

Registry: "Redirect Extended Community indirection_id"

Value Code Reference

0 Localised ID [RFC-To-Be]
1 Node ID [RFC-To-Be]
2 Agency ID [RFC-To-Be]
3 AS (Autonomous System) ID [RFC-To-Be]
4 Anycast ID [RFC-To-Be]
5 Multicast ID [RFC-To-Be]
6 Tunnel ID (Tunnel Binding ID ) [RFC-To-Be]
7 VPN ID [RFC-To-Be]
8 OAM ID [RFC-To-Be]
9 ECMP (Equal Cost Multi-Path) ID [RFC-To-Be]
10 QoS ID [RFC-To-Be]
11 Bandwidth-Guarantee ID [RFC-To-Be]
12 Security ID [RFC-To-Be]
13 Multi-Topology ID [RFC-To-Be]

Figure 3

10. References
10.1. Normative References

[1] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997,
<http://xml.resource.org/public/rfc/html/rfc2119.html>.

[2] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
<http://www.rfc-editor.org/info/rfc5575>.

10.2. Informative References

[3] Uttaro, J., Filsfils, C., Alcaide, J., and P. Mohapatra,
"Revised Validation Procedure for BGP Flow
Specifications", January 2014.

[4] Filsfils, C., Previdi, S., Aries, E., Ginsburg, D., and D.
Afanasiev, "Segment Routing Centralized Egress Peer
Engineering", October 2015.

[5] Sreekantiah, A., Filsfils, C., Previdi, S., Sivabalan, S.,
Mattes, P., and S. Lin, "Segment Routing Traffic
Engineering Policy using BGP", October 2015.

[6] Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
Shakir, R., Bashandy, A., Horneffer, M., Henderickx, W.,
Tantsura, J., Crabbe, E., Milojevic, I., and S. Ytti,
"Segment Routing Architecture", December 2015.

[7] Sivabalan, S., Medved, M., Filsfils, C., Litkowski, S.,
Raszuk, R., Bashandy, A., Lopez, V., Tantsura, J.,
Henderickx, W., Hardwick, J., Milojevic, I., and S. Ytti,
"PCEP Extensions for Segment Routing", December 2015.

Authors' Addresses

Gunter Van de Velde (editor)
Alcatel-Lucent
Nokia
Antwerp
BE

Email: gunter.van_de_velde@alcatel-lucent.com gunter.van_de_velde@nokia.com
Wim Henderickx
Alcatel-Lucent
Nokia
Antwerp
BE

Email: wim.henderickx@alcatel-lucent.com wim.henderickx@nokia.com

Keyur Patel
Cisco Systems
170 W. Tasman Drive
San Jose, CA 95134
USA

Email: keyupate@cisco.com

Arjun Sreekantiah
Cisco Systems
170 W. Tasman Drive
San Jose, CA 95134
USA

Email: asreekan@cisco.com

Zhenbin Li
Huawei Technologies
Huawei Bld., No. 156 Beiquing Rd
Beijing 100095
China

Email: lizhenbin@huawei.com

Shunwan Zhuang
Huawei Technologies
Huawei Bld., No. 156 Beiquing Rd
Beijing 100095
China

Email: zhuangshunwan@huawei.com
Nan Wu
Huawei Technologies
Huawei Bld., No. 156 Beiquing Rd
Beijing 100095
China

Email: eric.wu@huawei.com