Internet DRAFT - draft-dt-rtgwg-dcrouting-requirements
draft-dt-rtgwg-dcrouting-requirements
RTGWG J. Tantsura
Internet-Draft Individual
Intended status: Informational D. Afanasiev
Expires: May 3, 2018 YANDEX
K. Patel
Arccus
P. Lapukhov
Facebook
P. Przygienda
Juniper
R. White
LinkedIn
Y. Qu
Huawei
J. Uttaro
ATT
October 30, 2017
Requirements for the DataCenter Routing
draft-dt-rtgwg-dcrouting-requirements-00
Abstract
This document describes list of functional requirments towards a
Routing Protocol for Data Center Networks.
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 May 3, 2018.
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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 . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Recommended Reading . . . . . . . . . . . . . . . . . . . . . 3
4. Goals and Requirements . . . . . . . . . . . . . . . . . . . 3
5. For further study . . . . . . . . . . . . . . . . . . . . . . 5
6. Network Topologies . . . . . . . . . . . . . . . . . . . . . 5
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
8. Security Considerations . . . . . . . . . . . . . . . . . . . 5
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
10. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 5
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
11.1. Normative References . . . . . . . . . . . . . . . . . . 5
11.2. Informative References . . . . . . . . . . . . . . . . . 5
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
It is common to host and build a network of more than tens of
thousands of end points inside a data center. Data Center Networks
of such size have unique set of requirements with emphasis on scale,
convergence, network stability and opertional simplicity. Existing
or new set of protocols and routing infrastructure needs to be
augmented to support higher scale, faster convergence with increased
optional simplicity in order to address the requirements of these
networks.
This document describes list of functional requirements that are
required towards addressing scale, convergence and operational
maintainance of such scaled networks. The requirements described in
this document can be used to augment existing solutions or used to
design a new set of solutions.
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2. 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 [RFC2119] only when
they appear in all upper case. They may also appear in lower or
mixed case as English words, without any normative meaning.
3. Recommended Reading
This document assumes knowledge of existing data center networks and
data center network topologies [CLOS],[RFC7938]. This document also
assumes knowledge of data center routing protocols like BGP
[RFC4271], OSPF [RFC2328] and BFD [RFC5880] as well as data center
layer 2 link layer protocols like LLDP [RFC4957].
4. Goals and Requirements
Following are general requirements for the Data Center Network Fabric
and its Routing Protocols:
o The Fabric provides basic connectivity, with possibility to carry
one or more overlays.
The Fabric provides no domain separation, if needed, to be handled
by an overlay.
The Fabric MAY provide interconnect facility for other fabrics.
The Fabric MUST support non equidistant end-points.
o The Fabric MUST support Spine and Leaf [CLOS] + isomorphic
topologies within its network.
The Fabric MAY support non Spine and Leaf topologies
o The KPI's below are single-dimensional and expected to be changed,
as the document progresses, baseded on more feedback, we ask
community to communicate their views. Combination of # of routes
vs # of paths vs desired convergence time will be discussed in a
later version.
The Fabric SHOULD support 250k routes @ 5k fabric nodes with
convergence time below 250ms.
The Fabric SHOULD support 500k routes @ 7.5k fabric nodes with
convergence time below 500ms.
The Fabric SHOULD support 1M routes @ 10k fabric nodes with
convergence time below 1s.
o The Fabric routing protocol MUST support load balancing using
ECMP, wECMP and UCMP.
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The Fabric routing protocol MAY support any custom or adaptive
load balancing algorithms.
The Fabric routing protocol MUST support and provide facility for
topology-specific algorithms that enable correct operations in
that specific topology.
o The Fabric routing protocol SHOULD support route scale and
convergence times of a Fabric mentioned above.
The Fabric routing protocol SHOULD support ECMP as wide as 256
paths.
o The Fabric routing protocol MUST support various address families
that covers IP as well as MPLS forwarding.
The Fabric routing protocol MUST support extensions to carry 3rd
party data and Opaque data.
o The Fabric routing protocol MUST support Traffic Engineering paths
that are host and/or router based paths.
The Fabric routing protocol MUST provide facility to address
constituents in an ECMP bundle.
o The Fabric routing protocol MUST support inband as well as out of
band management.
o The Fabric routing protocol MUST support Zero Touch Provisioning
(ZTP).
The Fabric routing protocol MUST support Neighbor Discovery to
facilitate ZTP.
o The Fabric routing protocol MUST be able to leverage BFD [RFC5880]
for neighbor state.
The Fabric routing protocol SHOULD be capable of bootstrapping a
BFD session [RFC5882].
o The Fabric routing protocol MUST be able to support real time
state notifications of routes and its neighbors state to
facilitate control plane telemetry.
The Fabric routing protocol MUST be able to support on-demand
snapshots of protocol state and real time state notifications of
routes and its neighbors state to remote node(s) to facilitate
control plane telemetry.
o The Fabric routing protocol MUST be able handle commission/
decommission of a node as well as any node restart with a minimal
data plane impact.
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5. For further study
Following topics have been identified to be studied at a later time:
o gRPC/THRIFT/similar encodings.
o Ability to function as an overlay.
o Flowlets signaling.
o Multicast.
o State representation NB.
o Integration with PCE/SDNc.
6. Network Topologies
7. IANA Considerations
8. Security Considerations
This document describes list of functional requirements towards a
routing protocol for Data Center Networks. It does not raise any
security concerns or issues in addition to ones common to a routing
protocol for Data Center Networks.
9. Acknowledgements
10. Change Log
Initial Version: October 31 2017
11. References
11.1. 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,
<https://www.rfc-editor.org/info/rfc2119>.
11.2. Informative References
[CLOS] "A Study of Non-Blocking Switching Networks", The Bell
System Technical Journal, Vol. 32(2), DOI
10.1002/j.1538-7305.1953.tb01433.x, March 1953.
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[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4957] Krishnan, S., Ed., Montavont, N., Njedjou, E., Veerepalli,
S., and A. Yegin, Ed., "Link-Layer Event Notifications for
Detecting Network Attachments", RFC 4957,
DOI 10.17487/RFC4957, August 2007,
<https://www.rfc-editor.org/info/rfc4957>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<https://www.rfc-editor.org/info/rfc5880>.
[RFC5882] Katz, D. and D. Ward, "Generic Application of
Bidirectional Forwarding Detection (BFD)", RFC 5882,
DOI 10.17487/RFC5882, June 2010,
<https://www.rfc-editor.org/info/rfc5882>.
[RFC7938] Lapukhov, P., Premji, A., and J. Mitchell, Ed., "Use of
BGP for Routing in Large-Scale Data Centers", RFC 7938,
DOI 10.17487/RFC7938, August 2016,
<https://www.rfc-editor.org/info/rfc7938>.
Authors' Addresses
Jeff Tantsura
Individual
USA
Email: jefftant.ietf@gmail.com
Dmitry Afanasiev
YANDEX
RU
Email: dmitry.afanasiev@gmail.com
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Keyur Patel
Arccus
San Jose
USA
Email: keyur@arrcus.com
Petr Lapukhov
Facebook
USA
Email: petr@fb.com
Tony Przygienda
Juniper
1137 Innovation Way
Sunnyvale, CA
USA
Email: prz@juniper.net
Russ White
LinkedIn
USA
Email: russ@riw.us
Yingzhen Qu
Huawei
Santa Clara
USA
Email: yingzhen.ietf@gmail.com
Jim Uttaro
ATT
USA
Email: juttaro@ieee.org
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