Internet-Draft BMP Monitoring Options September 2026
Geng & Zhuang Expires 3 April 2027 [Page]
Workgroup:
GROW
Internet-Draft:
draft-geng-grow-bmp-monitor-options-00
Published:
Intended Status:
Standards Track
Expires:
Authors:
N. Geng
Huawei Technologies
S. Zhuang
Huawei Technologies

BMP Extension for Monitoring Options (MO) Notification

Abstract

The BGP Monitoring Protocol (BMP) allows routers to export BGP RIB data and statistics to external collectors. However, dynamic changes to a router's monitoring configuration—such as disabling specific Address Families or statistic counters—are not explicitly signaled to the collector. Consequently, collectors cannot distinguish between a quiescent BGP state and a disabled monitoring feed, leading to data staleness and database pollution.

This document defines a new BMP message type, the BMP Monitoring Options (MO) message. It allows a BMP Sender to explicitly notify collectors of active, disabled, or dynamically altered reporting configurations across RIB types and statistics streams.

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/.

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This Internet-Draft will expire on 3 April 2027.

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Table of Contents

1. Introduction

Modern networks frequently adjust BMP telemetry parameters based on network load, operational focus, or troubleshooting needs. For instance, an operator may dynamically disable Adj-RIB-Out reporting or stop monitoring specific VPN address families via router CLI.

Under [RFC7854], BMP provides no in-band mechanism for a sender to signal configuration changes to a collector. When an address family's monitoring is disabled on the router, the sender simply stops sending BMP messages for that family. The collector cannot determine whether no updates are occurring or if the stream was administratively disabled. As a result, stored RIB views become stale and invalid.

This document defines the BMP Monitoring Options (MO) message (Type TBD2). This message explicitly signals enabled or disabled state for RIB address families and statistic types, ensuring real-time database hygiene on the collector.

2. Terminology

3. BMP Monitoring Options Message Structure

The BMP Monitoring Options message (Type TBD2) follows the Common BMP Header and optional Per-Peer Header. Two distinct PDU formats are defined: RIB Options PDU and Statistics Options PDU.

3.1. RIB Options PDU Format

 0                   1                   2                   3
 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              |            SubType            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Flags             |            Length             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             AFI 1             |   Reserved    |     SAFI 1    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                               ...                             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             AFI n             |   Reserved    |     SAFI n    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 1: BMP RIB Monitoring Options PDU

Fields:

3.2. Stats Options PDU Format

 0                   1                   2                   3
 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              |            Flags              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |          Stat Type 1          |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|          Stat Type 2          |              ...              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

              Figure 2: BMP Stats Monitoring Options PDU

Fields:

4. Operational Workflow

4.1. Initial Capabilities Exchange & Administrative State Change

Upon establishing a BMP session, the sender SHOULD transmit an initial MO message enumerating all currently active monitoring options.

When an operator disables monitoring for a specific family (e.g., AFI=1, SAFI=2) via CLI:

  1. The BMP Sender MUST immediately transmit an MO Message with Type=Adj-RIB-In, LSB(Flags)=0, and payload=(AFI=1, SAFI=2).

  2. Upon receipt, the Collector MUST immediately purge all stored RIB entries associated with that disabled <Peer, AFI, SAFI> view.

4.2. Example Usage of BMP Monitoring Options Messages

Consider a topology where a BGP session is established between Router1 and Router2. Three address families are enabled on both BGP speakers: IPv4 Unicast (AFI=1, SAFI=1), IPv4 Multicast (AFI=1, SAFI=2), and IPv4 Labeled Unicast (AFI=1, SAFI=4). Router1 acts as the BMP Sender streaming data to the BMP Collector.

 BMP Collector
       |
       |
       |                 BGP Session
    Router1 (BMP Sender) ------------ Router2

           Figure 3: Topology Example for BMP MO

1. Initial Export Sequence:

Upon initializing the BMP session, the BMP Sender exports initial Route Monitoring messages for all three active address families.

 BMP Sender                               BMP Collector
  ~                                           ~
  |---------------- Initial Export ---------->| Sender sends Route
  |                                           | Monitoring messages for
  |                                           | IPv4 Unicast, Multicast,
  |                                           | and Labeled Unicast
  |                                           |
  |                                           | Collector stores RIB info
  |                                           | for all three families

        Figure 4: Initial Route Monitoring Export Sequence

2. Disabling Monitoring Options:

When an operator dynamically disables monitoring for the IPv4 Multicast address family (AFI=1, SAFI=2) on the sender:

 BMP Sender                               BMP Collector
  |-- MO Msg (AFI 1/SAFI 2, Disable) -------->| Sender sends MO Message
  |                                           |
  |                                           | Collector purges the IPv4
  |                                           | Multicast RIB view for
  |                                           | this specific BGP peer

      Figure 5: Disabling Monitoring for IPv4 Multicast Family

Similarly, if monitoring for IPv4 Labeled Unicast (AFI=1, SAFI=4) is subsequently disabled:

 BMP Sender                               BMP Collector
  |-- MO Msg (AFI 1/SAFI 4, Disable) -------->| Sender sends MO Message
  |                                           |
  |                                           | Collector purges the IPv4
  |                                           | Labeled Unicast RIB view
  |                                           | for this specific peer

   Figure 6: Disabling Monitoring for IPv4 Labeled Unicast Family

3. Re-enabling Monitoring Options:

When monitoring for IPv4 Multicast (AFI=1, SAFI=2) is re-enabled, the sender notifies the collector via an MO message and resumes streaming Route Monitoring messages for that view:

 BMP Sender                               BMP Collector
  |-- MO Msg (AFI 1/SAFI 2, Enable) --------->| Sender sends MO Message
  |                                           |
  |-- BMP RM Msg (AFI 1/SAFI 2) ------------->| Sender streams Route
  |-- .......... ---------------------------->| Monitoring updates for
  |-- BMP RM Msg (AFI 1/SAFI 2) ------------->| IPv4 Multicast view
  |                                           |
  |                                           | Collector restores and
  |                                           | stores the RIB view

       Figure 7: Re-enabling Monitoring for IPv4 Multicast Family

5. Security Considerations

Unauthorized MO messages could trick a collector into purging its entire monitored database by sending fake "Disable" options. Mutual authentication and transport protection (e.g., TLS) MUST be used.

6. IANA Considerations

This document requests IANA to allocate a new message type code from the "BMP Message Types" registry:

+------+-------------------------------+---------------+
| Type | Description                   | Reference     |
+------+-------------------------------+---------------+
| TBD2 | BMP Monitoring Options (MO)   | This document |
+------+-------------------------------+---------------+

IANA is also requested to create a new sub-registry: "BMP Monitoring Options PDU Types":

7. Acknowledgements

TBD

8. References

8.1. Normative References

[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/info/rfc2119>.
[RFC2918]
Chen, E., "Route Refresh Capability for BGP-4", RFC 2918, DOI 10.17487/RFC2918, , <https://www.rfc-editor.org/info/rfc2918>.
[RFC4271]
Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, DOI 10.17487/RFC4271, , <https://www.rfc-editor.org/info/rfc4271>.
[RFC7313]
Patel, K., Chen, E., and B. Venkatachalapathy, "Enhanced Route Refresh Capability for BGP-4", RFC 7313, DOI 10.17487/RFC7313, , <https://www.rfc-editor.org/info/rfc7313>.
[RFC7854]
Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP Monitoring Protocol (BMP)", RFC 7854, DOI 10.17487/RFC7854, , <https://www.rfc-editor.org/info/rfc7854>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/info/rfc8174>.
[RFC8671]
Evens, T., Bayraktar, S., Lucente, P., Mi, P., and S. Zhuang, "Support for Adj-RIB-Out in the BGP Monitoring Protocol (BMP)", RFC 8671, DOI 10.17487/RFC8671, , <https://www.rfc-editor.org/info/rfc8671>.
[RFC9069]
Evens, T., Bayraktar, S., Bhardwaj, M., and P. Lucente, "Support for Local RIB in the BGP Monitoring Protocol (BMP)", RFC 9069, DOI 10.17487/RFC9069, , <https://www.rfc-editor.org/info/rfc9069>.

8.2. Informative References

Authors' Addresses

Nan Geng
Huawei Technologies
Huawei Campus, No. 156 Beiqing Road
Beijing
100095
China
Shunwan Zhuang
Huawei Technologies
Huawei Campus, No. 156 Beiqing Road
Beijing
100095
China