Definitions of Managed Objects for IEEE 802.3 Medium Attachment Units (MAUs)
obsoleted by
- rfc-3636 — Definitions of Managed Objects for IEEE 802.3 Medium Attachment Units (MAUs)
obsoletes
- rfc-2239 — Definitions of Managed Objects for IEEE 802.3 Medium Attachment Units (MAUs) using SMIv2
Extracted elements (28)
ifMauTypeList and the integer-encoded auto-negotiation capability objects (ifMauAutoNegCapability, ifMauAutoNegCapAdvertised, ifMauAutoNegCapReceived) were deprecated in favor of BITS-typed replacements to support capability sets larger than 32 bits and to allow future extensibility without integer encoding arithmetic.
Internal MAUs (whose functionality is implemented entirely within a device, such as a repeater's internal management MAU) are optionally managed; if managed, their objects appear in dot3RpMauBasicGroup or dot3IfMauBasicGroup respectively, using the same MIB structure as external MAUs.
This MIB extends RFC 2239 (now historic) by adding management for 1000 Mb/s MAU types, PAUSE flow-control negotiation capability bits, and remote fault status signaling for 1000BASE-X auto-negotiation, reflecting the evolution of IEEE 802.3 from the 1998 edition.
A MIB conforming to SMIv1 can be produced by translating the SMIv2 module; however Counter64 objects cannot be translated and must be omitted, and machine-readable SMIv2 information is converted to textual descriptions, without changing the MIB semantics.
Agents implementing older MAU type OIDs dot3MauType10BaseT(5) and dot3MauType10BaseFL(8) SHOULD return the duplex-specific variants (HD/FD) when the duplex mode is known; management applications MUST be prepared to receive the generic type value from older agent implementations.
For MAUs where an IEEE 802.3u clause 22 MII is present, a logic one in the MII remote fault bit maps to remoteFault(5) and a logic zero in the link status bit maps to notAvailable(4); notAvailable(4) takes precedence over remoteFault(5) when both conditions apply.
An agent implementing interface-MAU related objects MUST also implement the relevant groups of the Interface MIB (RFC 2233). The value of ifMauIfIndex must equal the ifIndex used to instantiate the interface to which the MAU is connected.
An agent implementing repeater-MAU related objects MUST also implement the 802.3 Repeater MIB (RFC 2108). The values of rpMauGroupIndex and rpMauPortIndex SHALL be the same as rptrPortGroupIndex and rptrPortIndex for the connected port.
The agent MUST always return other(1) for ifMauJabberState and rpMauJabberState when the MAU type is dot3MauTypeAUI.
The rpMauFalseCarriers counter increments only for dot3MauType100BaseT4, dot3MauType100BaseTX, dot3MauType100BaseFX, and all 1000 Mbps types; for all other MAU types it MUST always indicate zero. It can increment at most once per 100 ms (100BASE-X) or once per 10 µs (1000BASE-X) after a valid carrier completion.
The values remoteJabber(7), remoteLinkLoss(8), and remoteTest(9) SHOULD be used instead of remoteFault(5) where the reason for the remote fault is identified in the remote signaling protocol.
When ifMauAutoNegAdminStatus transitions from enabled to disabled, the agent implementation MUST ensure that the operational MAU type (as reported by ifMauType) correctly transitions to the value specified by ifMauDefaultType, rather than continuing at the auto-negotiated value.
dot3MauType OID subtree defines 30 MAU type OBJECT-IDENTITY values, from dot3MauTypeAUI (1) through dot3MauType1000BaseTFD (30), covering all 10, 100, and 1000 Mbps physical media types with explicit half/full duplex variants where applicable.
ifMauAutoNegCapabilityBits, ifMauAutoNegCapAdvertisedBits, and ifMauAutoNegCapReceivedBits are 16-bit BITS objects covering 10BASE-T through 1000BASE-T plus four PAUSE variants (symmetric, asymmetric, and combinations). They replace the deprecated integer-encoded ifMauAutoNegCapability, ifMauAutoNegCapAdvertised, and ifMauAutoNegCapReceived objects.
ifMauAutoNegConfig reports the current auto-negotiation process state as one of: other(1), configuring(2), complete(3), disabled(4), or parallelDetectFail(5), where parallelDetectFail maps to the failure condition defined in IEEE 802.3 clause 28.2.3.1.
ifMauAutoNegRemoteFaultAdvertised and ifMauAutoNegRemoteFaultReceived are read-write/read-only INTEGER objects for 1000 Mbps MAUs reporting fault conditions (noError, offline, linkFailure, autoNegError) that are exchanged during auto-negotiation via the RF1/RF2 bits.
ifMauAutoNegTable contains configuration and status for the auto-negotiation function on interface MAUs. Key objects include ifMauAutoNegAdminStatus (enable/disable), ifMauAutoNegRemoteSignaling (FLP Burst detection), ifMauAutoNegConfig (configuring/complete/disabled/parallelDetectFail), ifMauAutoNegRestart, and BITS-based capability objects.
ifMauDefaultType is a read-write OID that specifies the administratively configured MAU type. When auto-negotiation is disabled, it determines the operational type; when auto-negotiation transitions from enabled to disabled, the MAU must revert to this type.
ifMauTable provides descriptive and status information about MAU(s) attached to interfaces, indexed by ifMauIfIndex and ifMauIndex. Entries include type, status, media availability, jabber state, false carrier counter, default type, auto-negotiation support flag, and the ifMauTypeListBits capability field.
ifMauTypeListBits is a BITS object (31 named bits, b0–b30) that identifies all IEEE 802.3 MAU types the interface could operate as, covering AUI through 1000BASE-T full duplex. It replaces the deprecated integer-encoded ifMauTypeList object and maps to ifMauAutoNegCapabilityBits when auto-negotiation is present.
JackType textual convention enumerates 13 connector types: other(1), rj45(2), rj45S(3), db9(4), bnc(5), fAUI(6), mAUI(7), fiberSC(8), fiberMIC(9), fiberST(10), telco(11), mtrj(12), hssdc(13). Used by rpJackType and ifJackType in the jack tables.
rpJackTable and ifJackTable provide information about external connectors attached to repeater and interface MAUs respectively, indexed by the enclosing MAU indices plus a local rpJackIndex/ifJackIndex. Each entry contains only the JackType.
rpMauTable provides descriptive and status information about MAU(s) attached to repeater ports, indexed by rpMauGroupIndex, rpMauPortIndex, and rpMauIndex. Each entry contains type, status, media availability, jabber state, and counter objects.
IANA manages the assignment of OBJECT IDENTIFIERs for new MAU types under the dot3MauType subtree (snmpDot3MauMgt 4 = mib-2 26 4). If the MAU type is unknown, agents return the sentinel unknownMauType ::= { 0 0 }.
Several objects in this MIB (rpMauStatus, ifMauStatus, ifMauDefaultType, ifMauAutoNegAdminStatus, ifMauAutoNegCapAdvertisedBits, ifMauAutoNegRestart) are read-write and can affect network operation; unauthorized access could disrupt Ethernet links. Implementors should use SNMPv3 with authentication and privacy to protect these objects.
MAU administrative status (rpMauStatus / ifMauStatus) defines six states: other(1), unknown(2), operational(3), standby(4), shutdown(5), and reset(6). Writing reset(6) triggers a power-cycle equivalent; writing standby(4) to a mixing-type MAU or AUI causes entry into shutdown instead.
rpMauJabberState / ifMauJabberState reports four states: other(1), unknown(2), noJabber(3), jabbering(4). The agent MUST always return other(1) for MAU type dot3MauTypeAUI; the jabbering counter is always zero for AUI and all MAU types above 10 Mbps.
rpMauMediaAvailable / ifMauMediaAvailable reports link/media status via eleven states: other, unknown, available, notAvailable, remoteFault, invalidSignal, remoteJabber, remoteLinkLoss, remoteTest, offline, and autoNegError. For 100/1000 Mbps MAUs the states map to the link integrity state diagrams in IEEE 802.3 sections 23, 24, and 32.