OSPF Flooding Reduction in Massively Scalable Data Centers (MSDCs)
draft-xu-lsr-ospf-flooding-reduction-in-msdc-04
Network Working Group X. Xu
Internet-Draft Alibaba, Inc
Intended status: Standards Track L. Fang
Expires: June 24, 2021 Expedia, Inc
J. Tantsura
Apstra, Inc.
S. Ma
Juniper
December 21, 2020
OSPF Flooding Reduction in Massively Scalable Data Centers (MSDCs)
draft-xu-lsr-ospf-flooding-reduction-in-msdc-04
Abstract
OSPF is one of the used underlay routing protocol for MSDC (Massively
Scalable Data Center) networks. For a given OSPF router within the
CLOS topology, it would receive multiple copies of exactly the same
LSA from multiple OSPF neighbors. In addition, two OSPF neighbors
may send each other the same LSA simultaneously. The unnecessary
link-state information flooding wastes the precious process resource
of OSPF routers greatly due to the presence of too many OSPF
neighbors for each OSPF router within the CLOS topology. This
document proposes extensions to OSPF so as to reduce the OSPF
flooding within such MSDC networks. The reduction of the OSPF
flooding is much beneficial to improve the scalability of MSDC
networks. These modifications are applicable to both OSPFv2 and
OSPFv3.
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
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provisions of BCP 78 and BCP 79.
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Xu, et al. Expires June 24, 2021 [Page 1]
Internet-Draft December 2020
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 June 24, 2021.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Modifications to Legacy OSPF Behaviors . . . . . . . . . . . 4
3.1. OSPF Routers as Non-DRs . . . . . . . . . . . . . . . . . 4
3.2. Controllers as DR/BDR . . . . . . . . . . . . . . . . . . 5
4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
6. Security Considerations . . . . . . . . . . . . . . . . . . . 6
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
7.1. Normative References . . . . . . . . . . . . . . . . . . 6
7.2. Informative References . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
OSPF is commonly used as an underlay routing protocol for Massively
Scalable Data Center (MSDC) networks where CLOS is the most popular
topology. MSDCs are also called Large-Scale Data Centers.
For a given OSPF router within the CLOS topology, it would receive
multiple copies of exactly the same LSA from multiple OSPF neighbors.
In addition, two OSPF neighbors may send each other the same LSA
simultaneously. The unnecessary link-state information flooding
significantly wastes the precious process resource of OSPF routers
and therefore OSPF could not scale very well in MSDC networks.
Xu, et al. Expires June 24, 2021 [Page 2]
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