Definition of Managed Objects for IEEE 802.3 Repeater Devices
obsoleted by
- rfc-1516 — Definitions of Managed Objects for IEEE 802.3 Repeater Devices
Extracted elements (30)
The counters in this MIB are defined to be identical to those in the IEEE 802.3 Repeater Management draft (P802.3K) so that a single hardware instrumentation can satisfy both the IEEE and IETF management standards simultaneously.
The document is named 'Repeater MIB' rather than 'Hub MIB' to avoid confusion with modular concentrator chassis products that combine 802.3, token ring, and FDDI connectivity. The scope is strictly IEEE 802.3 repeater unit management.
The group-level monitor counters (rptrMonitorGroupTotalFrames, TotalOctets, TotalErrors) are acknowledged as redundant summations of per-port data, but are included explicitly because polling a single aggregated counter provides considerable optimization of network management traffic over retrieving all individual port counters.
The group/port numbering hierarchy (rptrGroupIndex 1..rptrGroupCapacity, rptrPortIndex 1..rptrGroupPortCapacity) was designed to support modular concentrator chassis where field-replaceable cards map naturally to groups and per-card port numbers match physical labeling.
A repeater implementing this MIB is assumed to also implement at least the 'system' group from MIB-II (RFC 1213). MAU management is explicitly out of scope and addressed in a separate memo.
The MIB-II 'interfaces' group has NO specific relationship to a repeater's ports. The interfaces group applies only to the network interface(s) used by the management entity; it does not apply to the repeater's forwarding ports, consistent with the physical-layer nature of a repeater.
Implementation of the Basic Group (rptrBasicPackage) is mandatory for all managed repeaters. It contains status, parameter, and control objects for the repeater as a whole, its port groups, and individual ports.
rptrResetEvent trap is not sent when the agent restarts and sends an SNMP coldStart or warmStart trap; however, it is recommended that a repeater agent include rptrOperStatus as an optional object in coldStart and warmStart trap PDUs.
The agent must throttle consecutive rptrHealth, rptrGroupChange, and rptrResetEvent traps for the same condition so that there is at least a five-second gap between consecutive transmissions of each trap type.
The Monitor Group and Address Tracking Group are optional, but if a managed repeater implements any part of either group, the entire group shall be implemented.
The value of rptrGroupCapacity must remain constant from one management restart to the next, as it defines the stable upper bound on the number of groups in the repeater.
The value of rptrGroupPortCapacity must not change for a given group; however, a group may be deleted and replaced with one containing a different port count, which is indicated by rptrGroupLastOperStatusChange.
When multiple failure kinds occur simultaneously, rptrOperStatus must reflect the highest-priority failure in the order: rptrFailure(3) > groupFailure(4) > portFailure(5) > generalFailure(6).
MacAddress is defined as a textual convention OCTET STRING (SIZE (6)), encoding a 6-octet MAC address in canonical (least-significant-bit-first) order as defined by IEEE 802.1a. This convention has no effect on encoding.
rptrGroupTable provides descriptive and status information per group, including rptrGroupIndex (1..1024), rptrGroupDescr, rptrGroupObjectID (vendor OID under enterprises subtree), rptrGroupOperStatus, rptrGroupLastOperStatusChange (TimeTicks), and rptrGroupPortCapacity (1..1024).
rptrMonitorPortFCSErrors counts frames with FCSError asserted and FramingError and CollisionEvent deasserted, with OctetCount in [minFrameSize, maxFrameSize]. If AlignmentErrors is incremented for a frame, FCSErrors shall not also be incremented for the same frame.
rptrMonitorPortLateEvents counts CarrierEvents where the CollIn(X) variable transitions to SQE while ActivityDuration exceeds LateEventThreshold (>480 and <565 bit times). Such events are counted both as a collision and as a lateEvent.
rptrMonitorPortShortEvents counts CarrierEvents with ActivityDuration less than ShortEventMaxTime (greater than 74 bit times, less than 82 bit times). Short events may indicate external noise hits causing the repeater to transmit runts or propagate late collisions.
rptrMonitorPortTotalErrors is the summation of FCSErrors, AlignmentErrors, FrameTooLongs, ShortEvents, LateEvents, VeryLongEvents, and DataRateMismatches for a port. It is explicitly included to optimize polling traffic by providing a single health-tracking counter.
rptrNonDisruptTest is a read-write object; setting it to selfTest(2) triggers a non-disruptive agent-specific self-test that does not change repeater state, inject packets, prevent packet relay, or interfere with management. After the test, health information is updated and an rptrHealth trap is sent.
rptrOperStatus indicates the overall operational state of the repeater with values: other(1), ok(2), rptrFailure(3), groupFailure(4), portFailure(5), generalFailure(6). In cases of multiple simultaneous failures, the highest-priority failure is reported in the order listed.
rptrPortAdminStatus (read-write) enables or disables a port. A disabled port neither transmits nor receives; it must be explicitly re-enabled. Disabling a port freezes rptrPortAutoPartitionState; enabling it resets the auto-partition state machine to notAutoPartitioned(1) via BEGIN.
rptrPortOperStatus reports port status as operational(1), notOperational(2), or notPresent(3). A port is operational(1) even when auto-partitioned; setting rptrPortAdminStatus to disabled(2) is expected to transition the port to notOperational(2) soon after.
rptrReset is a read-write object; setting it to reset(2) causes a transition to the START state of the IEEE 802.3 repeater state machine and triggers a disruptive self-test. Management counters and portAdminStatus parameters are not reset. A rptrResetEvent trap should be sent on completion.
The Address Tracking Group provides rptrAddrTrackLastSourceAddress (the MacAddress of the last readable frame received on a port) and rptrAddrTrackSourceAddrChanges (a counter of how many times the last source address has changed), indexed by group and port.
The Monitor Group port table (rptrMonitorPortEntry) tracks per-port counters: ReadableFrames, ReadableOctets, FCSErrors, AlignmentErrors, FrameTooLongs, ShortEvents, Runts, Collisions, LateEvents, VeryLongEvents, DataRateMismatches, AutoPartitions, and TotalErrors.
The SNMP-REPEATER-MIB is rooted at snmpDot3RptrMgt OBJECT IDENTIFIER ::= { mib-2 22 }, with three sub-packages: rptrBasicPackage (1), rptrMonitorPackage (2), and rptrAddrTrackPackage (3).
Three traps are defined: rptrHealth (sent when rptrOperStatus changes, must include rptrOperStatus), rptrGroupChange (sent when a group is added or removed, includes rptrGroupIndex), and rptrResetEvent (sent on completion of a management-triggered repeater reset, includes rptrOperStatus).
Security issues are not discussed in this memo. The document provides no authentication, access control, or integrity mechanisms for SNMP management of repeater devices.
rptrPortAutoPartitionState has two states: notAutoPartitioned(1) and autoPartitioned(2). Enabling a port via rptrPortAdminStatus exerts BEGIN on the auto-partition state machine, always entering notAutoPartitioned(1). Partition conditions are specified in the IEEE 802.3 Std Section 9 state machine.