BMP Extension for Monitoring
Options (MO) NotificationHuawei TechnologiesHuawei Campus, No. 156 Beiqing RoadBeijing100095Chinagengnan@huawei.comHuawei TechnologiesHuawei Campus, No. 156 Beiqing RoadBeijing100095Chinazhuangshunwan@huawei.com
Ops & Mgmt Area
GROWRIB View SynchronizationDraftThe 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.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
when, and only when,
they appear in all capitals, as shown here.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 , 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.MO: Monitoring OptionsThe 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.Fields:Type (2 octets):1: Adj-RIB-In2: Adj-RIB-Out3: Loc-RIBSubType (2 octets):1: Pre-Policy2: Post-PolicyFlags (2 octets):Bit 15 (LSB): Enable/Disable Flag. 1 = Options Enabled, 0 =
Options Disabled.Bits 0-14: Reserved for future expansion (MUST be 0).Length (2 octets): Total length of the trailing (AFI, SAFI)
list.Fields:Type (2 octets): MUST be 4 (Stats).Flags (2 octets): LSB indicates Enable (1) or Disable (0).Length (2 octets): Length of trailing Stat Type IDs .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:The BMP Sender MUST immediately transmit an MO Message with
Type=Adj-RIB-In, LSB(Flags)=0, and payload=(AFI=1, SAFI=2).Upon receipt, the Collector MUST immediately purge all stored
RIB entries associated with that disabled <Peer, AFI, SAFI>
view.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.1. Initial Export Sequence:Upon initializing the BMP session, the BMP Sender exports initial
Route Monitoring messages for all three active address families.| 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:| 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:| 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:| 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
]]>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.This document requests IANA to allocate a new message type code from
the "BMP Message Types" registry:IANA is also requested to create a new sub-registry: "BMP
Monitoring Options PDU Types":1: Adj-RIB-In2: Adj-RIB-Out3: Loc-RIB4: StatsTBD