BGP Maximum Prefix Limits
draft-sa-grow-maxprefix-01
Global Routing Operations J. Snijders
Internet-Draft NTT Communications
Intended status: Standards Track M. Aelmans
Expires: June 30, 2019 Juniper Networks
December 27, 2018
BGP Maximum Prefix Limits
draft-sa-grow-maxprefix-01
Abstract
This document describes mechanisms to limit the negative impact of
route leaks [RFC7908] and/or resource exhaustion in BGP-4 [RFC4271]
implementations.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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 https://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 June 30, 2019.
Copyright Notice
Copyright (c) 2018 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
Snijders & Aelmans Expires June 30, 2019 [Page 1]
Internet-Draft BGP Maximum Prefix Limits December 2018
(https://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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Application of Control Theory to BGP-4 Operations . . . . . . 2
3. Inbound Maximum Prefix Limits . . . . . . . . . . . . . . . . 2
3.1. Type A: Pre-Policy Inbound Maximum Prefix Limits . . . . 3
3.2. Type B: Post-Policy Inbound Maximum Prefix Limits . . . . 3
4. Outbound Maximum Prefix Limits . . . . . . . . . . . . . . . 3
5. Considerations for Operations with Multi-Protocol BGP-4 . . . 4
6. Considerations for soft thresholds . . . . . . . . . . . . . 4
7. Security Considerations . . . . . . . . . . . . . . . . . . . 4
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 5
10. Implementation status - RFC EDITOR: REMOVE BEFORE PUBLICATION 5
11. Appendix: Implementation Guidance . . . . . . . . . . . . . . 6
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
12.1. Normative References . . . . . . . . . . . . . . . . . . 6
12.2. Informative References . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
This document describes mechanisms to reduce the negative impact of
certain types of misconfigurations and/or resource exhaustions in
BGP-4 [RFC4271] operations. While [RFC4271] already described a
method to tear down BGP-4 sessions when certain thresholds are
exceeded, some nuances in this specification were missing resulting
in inconsistencies between BGP-4 implementations. In addition to
clarifying "inbound maximum prefix limits", this document also
introduces a specification for "outbound maximum prefix limits".
2. Application of Control Theory to BGP-4 Operations
3. Inbound Maximum Prefix Limits
An operator MAY configure a BGP speaker to terminate its BGP session
with a neighbor when the number of address prefixes received from
that neighbor exceeds a locally configured upper limit. The BGP
speaker then MUST send the neighbor a NOTIFICATION message with the
Error Code Cease and the Error Subcode "Threshold reached: Maximum
Snijders & Aelmans Expires June 30, 2019 [Page 2]
Internet-Draft BGP Maximum Prefix Limits December 2018
Number of Prefixes Received", and MAY support other actions.
Show full document text