Definitions of Managed Objects for the Ethernet-like Interface Types Mon Oct 1 13:27:00 1990 Transmission MIB Working Group J. Cook (editor) Chipcom Corporation 118 Turnpike Road Southborough, MA 01772 cook@chipcom.com 1. Status of this Memo This draft document will be submitted to the RFC editor as an experimental extension to the SNMP MIB. Distribution of this memo is unlimited. Please send comments to the editor. 2. Abstract This memo defines an experimental portion of the Management Information Base (MIB) for use with network management protocols in TCP/IP-based internets. In particular, it defines objects for managing ethernet-like objects. This memo does not specify a standard for the Internet community. However, after experimentation, if sufficient consensus is reached in the Internet community, then a subsequent revision of this document may be incorporated into the Internet-standard MIB. Internet Draft ETHERNET-LIKE OBJECTS September 1990 3. Historical Perspective As reported in RFC 1052, IAB Recommendations for the Development of Internet Network Management Standards [1], a two-prong strategy for network management of TCP/IP-based internets was undertaken. In the short-term, the Simple Network Management Protocol (SNMP), defined in RFC 1067, was to be used to manage nodes in the Internet community. In the long-term, the use of the OSI network management framework was to be examined. Two documents were produced to define the management information: RFC 1065, which defined the Structure of Management Information (SMI), and RFC 1066, which defined the Management Information Base (MIB). Both of these documents were designed so as to be compatible with both the SNMP and the OSI network management framework. This strategy was quite successful in the short-term: Internet-based network management technology was fielded, by both the research and commercial communities, within a few months. As a result of this, portions of the Internet community became network manageable in a timely fashion. As reported in RFC 1109, Report of the Second Ad Hoc Network Management Review Group [2], the requirements of the SNMP and the OSI network management frameworks were more different than anticipated. As such, the requirement for compatibility between the SMI/MIB and both frameworks was suspended. This action permitted the operational network management framework, based on the SNMP, to respond to new operational needs in the Internet community by producing MIB-II. In May of 1990, the core documents were elevated to "Standard Protocols" with "Recommended" status. As such, the Internet- standard network management framework consists of: Structure and Identification of Management Information for TCP/IP-based internets, RFC 1155 [3], which describes how managed objects contained in the MIB are defined; Management Information Base for Network Management of TCP/IP-based internets, which describes the managed objects contained in the MIB, RFC 1156 [4]; and, the Simple Network Management Protocol, RFC 1157 [5], which defines the protocol used to manage these objects. Consistent with the IAB directive to produce simple, workable systems in the short-term, the list of managed objects defined in the Internet-standard MIB was derived by taking only those J. Cook (editor) [Page 2] Internet Draft ETHERNET-LIKE OBJECTS September 1990 elements which are considered essential. However, the SMI defined three extensibility mechanisms: one, the addition of new standard objects through the definitions of new versions of the MIB; two, the addition of widely-available but non- standard objects through the experimental subtree; and three, the addition of private objects through the enterprises subtree. Such additional objects can not only be used for vendor-specific elements, but also for experimentation as required to further the knowledge of which other objects are essential. This memo defines extensions to the MIB using the second method. It contains definitions of managed objects used for experimentation. After experimentation, if sufficient consensus is reached in the Internet community, then a subsequent revision of this memo may be placed in the Internet-standard MIB. J. Cook (editor) [Page 3] Internet Draft ETHERNET-LIKE OBJECTS September 1990 4. Objects Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the subset of Abstract Syntax Notation One (ASN.1) [7] defined in the SMI. In particular, each object has a name, a syntax, and an encoding. The name is an object identifier, an administratively assigned name, which specifies an object type. The object type together with an object instance serves to uniquely identify a specific instantiation of the object. For human convenience, we often use a textual string, termed the OBJECT DESCRIPTOR, to also refer to the object type. The syntax of an object type defines the abstract data structure corresponding to that object type. The ASN.1 language is used for this purpose. However, the SMI [3] purposely restricts the ASN.1 constructs which may be used. These restrictions are explicitly made for simplicity. The encoding of an object type is simply how that object type is represented using the object type's syntax. Implicitly tied to the notion of an object type's syntax and encoding is how the object type is represented when being transmitted on the network. The SMI specifies the use of the basic encoding rules of ASN.1 [8], subject to the additional requirements imposed by the SNMP. 4.1. Format of Definitions Section 6 contains contains the specification of all object types contained in this MIB module. The object types are defined using the conventions defined in the SMI, as amended by the extensions specified in [13,14]. J. Cook (editor) [Page 4] Internet Draft ETHERNET-LIKE OBJECTS September 1990 5. Overview Instances of these object types represent attributes of an interface to an ethernet-like communications medium. At present, ethernet-like media are identified by three values of the ifType object in the Internet-standard MIB: ethernet-csmacd(6) iso88023-csmacd(7) starLan(11) The definitions presented here are based on the IEEE 802.3 Layer Management Specification [9], as originally interpreted by Frank Kastenholz of Interlan in [10]. Implementors of these MIB objects should note that the IEEE document explicitly describes (in the form of Pascal pseudocode) when, where, and how various MAC attributes are measured. The IEEE document also describes the effects of MAC actions that may be invoked by manipulating instances of the MIB objects defined here. To the extent that some of the attributes defined in [9] are represented by previously defined objects in the Internet- standard MIB or in the generic interface extensions MIB [11], such attributes are not redundantly represented by objects defined in this memo. Among the attributes represented by objects defined in other memos are the number of octets transmitted or received on a particular interface, the number of frames transmitted or received on a particular interface, the promiscuous status of an interface, the MAC address of an interface, and multicast information associated with an interface. The relationship between an ethernet-like interface and an interface in the context of the Internet-standard MIB is one- to-one. As such, the value of an ifIndex object instance can be directly used to identify corresponding instances of the objects defined herein. J. Cook (editor) [Page 5] Internet Draft ETHERNET-LIKE OBJECTS September 1990 6. Definitions RFCxxxx-MIB DEFINITIONS ::= BEGIN IMPORTS experimental, Counter FROM RFC1155-SMI OBJECT-TYPE FROM RFC-oooo TRAP-TYPE FROM RFC-tttt; -- This MIB module uses the extended OBJECT-TYPE macro as -- defined in [13], and the TRAP-TYPE macro as defined in [14] -- this is the MIB module for ethernet-like objects dot3 OBJECT IDENTIFIER ::= { experimental 3 } J. Cook (editor) [Page 6] Internet Draft ETHERNET-LIKE OBJECTS September 1990 -- the Generic Ethernet-like group -- Implementation of this group is mandatory for all systems -- that attach to an ethernet-like medium. dot3Table OBJECT-TYPE SYNTAX SEQUENCE OF Dot3Entry ACCESS not-accessible STATUS mandatory DESCRIPTION "Operational attributes for a collection of ethernet-like interfaces attached to a particular system." ::= { dot3 1 } dot3Entry OBJECT-TYPE SYNTAX Dot3Entry ACCESS not-accessible STATUS mandatory DESCRIPTION "Operational attributes of a particular interface to an ethernet-like medium." INDEX { dot3Index } ::= { dot3Table 1 } Dot3Entry ::= SEQUENCE { dot3Index INTEGER, dot3InitializeMAC INTEGER, dot3MACSubLayerStatus INTEGER, dot3MulticastReceiveStatus INTEGER, dot3AlignmentErrors Counter, dot3FCSErrors Counter } dot3Index OBJECT-TYPE SYNTAX INTEGER ACCESS read-only STATUS mandatory J. Cook (editor) [Page 7] Internet Draft ETHERNET-LIKE OBJECTS September 1990 DESCRIPTION "An index value that uniquely identifies an interface to an ethernet-like medium. The interface identified by a particular value of this index is the same interface as identified by the same value of ifIndex." ::= { dot3Entry 1 } dot3InitializeMAC OBJECT-TYPE SYNTAX INTEGER { initialized(1), uninitialized(2) } ACCESS read-writ STATUS mandatory DESCRIPTION "The initialization status of the MAC and PLS (Physical Layer Signalling) subsystems for a particular interface. The value initialized(1) signifies that the subsystems for a particular interface have been previously initialized; the value uninitialized(2) signifies that they have not been previously initialized. Each alteration of an instance of this object to either of the values initialized(1) or uninitialized(2) is analogous to an invocation of the initializeMAC action defined in [9] and has the effect of (re-)initializing the MAC and PLS subsystems for the associated interface. In particular, all management counters pertaining to the MAC and PLS subsystems for said interface are reset to zero; The receive and transmit layer management state variables (receiveEnabled and transmitEnabled in [9]) are set to enable reception and transmission of frames; the promiscuous receive function is disabled; and multicast reception is disabled. " ::= { dot3Entry 2 } dot3MACSubLayerStatus OBJECT-TYPE J. Cook (editor) [Page 8] Internet Draft ETHERNET-LIKE OBJECTS September 1990 SYNTAX INTEGER { enabled(1), disabled(2) } ACCESS read-write STATUS mandatory DESCRIPTION "The operational status of the MAC sublayer for a particular interface. The value enabled(1) signifies that the MAC sublayer for said interface is operational for both transmitting and receiving frames -- that is, that the value of both the receive and transmit layer management state variables (receiveEnabled and transmitEnabled in [9]) for said interface are true. The value disabled(2) signifies that the MAC sublayer for said interface is not operational for either transmitting or receiving frames. In particular, the value of an instance of this object is disabled(2) whenever the value of the corresponding instance of the dot3XTxEnabled object is false(2). Each alteration of an instance of this object to the value enabled(1) is analogous to an invocation of the enableMACSublayer action defined in [9] and has the effect of starting normal transmit and receive operations (from the ``idle'' state) on the associated interface. In particular, such an alteration has the effect of resetting the PLS for said interface and of setting the receive and transmit layer management state variables (receiveEnabled and transmitEnabled in [9]) to be true. Each alteration of an instance of this object to the value disabled(2) is analogous to an invocation of the disableMACSublayer action defined in [9] and has the effect of terminating transmit and receive operations on the associated interface. In particular, such an alteration has the effect of setting the receive and transmit layer management state variables (receiveEnabled and transmitEnabled in [9]) to be false. Any transmissions/receptions in progress are completed before operation is terminated." ::= { dot3Entry 3 } J. Cook (editor) [Page 9] Internet Draft ETHERNET-LIKE OBJECTS September 1990 dot3MulticastReceiveEnabled OBJECT-TYPE SYNTAX INTEGER { true(1), false(2) } ACCESS read-write STATUS mandatory DESCRIPTION "The multicast receive status for a particular interface. The value true(1) signifies that reception of multicast frames by the MAC sublayer is enabled on said interface. The value false(1) signifies that reception of multicast frames by the MAC sublayer is not enabled on said interface. Each alteration of an instance of this object to the value true(1) is analogous to an invocation of the enableMulticastReceive action defined in [9] and has the effect of enabling multicast frame reception on the associated interface. Actual reception of multicast frames is only possible on an interface when the values for the associated instances of the dot3MulticastReceiveEnabled and dot3MACSubLayerStatus objects are true(1) and enabled(1), respectively. Each alteration of an instance of this object to the value false(2) is analogous to an invocation of the disableMulticastReceive action defined in [9] and has the effect of inhibiting multicast frame reception on the associated interface." ::= { dot3Entry 4 } dot3AlignmentErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames received on a particular interface that are not an integral number of octets in length and do not pass the FCS check. The count represented by an instance of this object is incremented when the alignmentError status is returned by the MAC service to the LLC (or other MAC user). Received frames for which multiple error conditions obtain are, according to the conventions of [9], counted exclusively J. Cook (editor) [Page 10] Internet Draft ETHERNET-LIKE OBJECTS September 1990 according to the error status presented to the LLC." ::= { dot3Entry 5 } dot3FCSErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames received on a particular interface that are an integral number of octets in length that do not pass the FCS check. The count represented by an instance of this object is incremented when the frameCheckError status is returned by the MAC service to the LLC (or other MAC user). Received frames for which multiple error conditions obtain are, according to the conventions of [9], counted exclusively according to the error status presented to the LLC." ::= { dot3Entry 6 } J. Cook (editor) [Page 11] Internet Draft ETHERNET-LIKE OBJECTS September 1990 -- the Ethernet-like Transmit group -- Implementation of this group is mandatory for all systems -- that transmit frames onto an ethernet-like medium. dot3TxTable OBJECT-TYPE SYNTAX SEQUENCE OF Dot3TxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Transmit errors and statistics for a collection of ethernet-like interfaces attached to a particular system." ::= { dot3 2 } dot3TxEntry OBJECT-TYPE SYNTAX Dot3TxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Transmit errors and statistics for a particular interface to an ethernet-like medium." INDEX { dot3TxIndex } ::= { dot3TxTable 1 } Dot3TxEntry ::= SEQUENCE { dot3TxIndex INTEGER, dot3TxSingleCollisionFrames Counter, dot3TxMultipleCollisionFrames Counter, dot3TxSQETestErrors Counter } dot3TxIndex OBJECT-TYPE SYNTAX INTEGER ACCESS read-only STATUS mandatory DESCRIPTION "An index value that uniquely identifies an interface to an ethernet-like medium. The interface identified by a particular value of this J. Cook (editor) [Page 12] Internet Draft ETHERNET-LIKE OBJECTS September 1990 index is the same interface as identified by the same value of ifIndex." ::= { dot3TxEntry 1 } dot3TxSingleCollisionFrames OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of successfully transmitted frames on a particular interface for which transmission is inhibited by exactly one collision. A frame that is counted by an instance of this object is also counted by the corresponding instance of either the ifOutUcastPkts or ifOutNUcastPkts object and is not counted by the corresponding instance of the dot3MultipleCollisionFrames object." ::= { dot3TxEntry 2 } dot3TxMultipleCollisionFrames OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of successfully transmitted frames on a particular interface for which transmission is inhibited by more than one collision. A frame that is counted by an instance of this object is also counted by the corresponding instance of either the ifOutUcastPkts or ifOutNUcastPkts object and is not counted by the corresponding instance of the dot3SingleCollisionFrames object." ::= { dot3TxEntry 3 } dot3TxSQETestErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandator DESCRIPTION "A count of times that the SQE TEST ERROR message is generated by the PLS sublayer for a particular J. Cook (editor) [Page 13] Internet Draft ETHERNET-LIKE OBJECTS September 1990 interface. The SQE TEST ERROR message is defined in section 7.2.2.2.4 of [12] and its generation is described in section 7.2.4.6 of the same document." ::= { dot3TxEntry 4 } J. Cook (editor) [Page 14] Internet Draft ETHERNET-LIKE OBJECTS September 1990 -- the Ethernet-like Extended Receive group -- Implementation of this group is optional; it is -- appropriate for all systems which the necessary metering -- is feasible. dot3XRxTable OBJECT-TYPE SYNTAX SEQUENCE OF Dot3XRxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Receive errors and statistics for a collection of ethernet-like interfaces attached to a particular system." ::= { dot3 3 } dot3XRxEntry OBJECT-TYPE SYNTAX Dot3XRxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Receive errors and statistics for a particular interface to an ethernet-like medium." INDEX { dot3XRxIndex } ::= { dot3XRxTable 1 } Dot3XRxEntry ::= SEQUENCE { dot3XRxIndex INTEGER, dot3XRxFrameTooLongs Counter, dot3XRxInRangeLengthErrors Counter, dot3XRxOutOfRangeLengthFields Counter, dot3XRxInternalMACReceiveErrors Counter, dot3XRxAutoPartitionStatus INTEGER, dot3XRxAutoPartitionLog Counter, dot3XRxLastSourceAddress OCTET STRING, dot3XRxSourceAddressLog J. Cook (editor) [Page 15] Internet Draft ETHERNET-LIKE OBJECTS September 1990 Counter, dot3XRxLastErrorAddress OCTET STRING, dot3XRxErrorAddressLog Counter } dot3XRxIndex OBJECT-TYPE SYNTAX INTEGER ACCESS read-only STATUS mandatory DESCRIPTION "An index value that uniquely identifies an interface to an ethernet-like medium. The interface identified by a particular value of this index is the same interface as identified by the same value of ifIndex." ::= { dot3XRxEntry 1 } dot3XRxFrameTooLongs OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames received on a particular interface that exceed the maximum permitted frame size. The count represented by an instance of this object is incremented when the frameTooLong status is returned by the MAC service to the LLC (or other MAC user). Received frames for which multiple error conditions obtain are, according to the conventions of [9], counted exclusively according to the error status presented to the LLC." ::= { dot3XRxEntry 2 } dot3XRxInRangeLengthErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames received on a particular interface with a length field value that falls J. Cook (editor) [Page 16] Internet Draft ETHERNET-LIKE OBJECTS September 1990 between the minimum unpadded LLC data size and the maximum allowed LLC data size inclusive and that does not match the number of LLC data octets received. The count represented by an instance of this object also includes frames for which the length field value is less than the minimum unpadded LLC data size." ::= { dot3XRxEntry 3 } dot3XRxOutOfRangeLengthFields OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames received on a particular interface for which the length field value exceeds the maximum allowed LLC data size. The count represented by an instance of this object is not incremented in implementations that observe Ethernet encapsulation conventions (by which the IEEE 802.3 length field is interpreted as the Ethernet Type field)." ::= { dot3XRxEntry 4 } dot3XRxInternalMACReceiveErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames for which reception on a particular interface fails due to an internal MAC sublayer receive error. A frame counted by an instance of this object is not counted by the corresponding instance of either the dot3XRxFrameTooLongs object, the dot3XRxAlignmentErrors object, the dot3XRxFCSErrors object, the dot3XRxInRangeLengthErrors object, or the dot3XRxOutOfRangeLengthFields object. The precise meaning of the count represented by an instance of this object is implementation- J. Cook (editor) [Page 17] Internet Draft ETHERNET-LIKE OBJECTS September 1990 specific. In particular, an instance of this object may represent a count of receive errors on a particular interface that are not otherwise counted." ::= { dot3XRxEntry 5 } dot3XRxAutoPartitionStatus OBJECT-TYPE SYNTAX INTEGER { partitioned(1), notPartitioned(2) } ACCESS read-write STATUS mandatory DESCRIPTION "The current auto-partition status for a particular interface. An instance of this object represents whether or not said interface is currently detached from the medium as the result of local, automatic detection of excessive or ill-formed transmissions initiated by said interface. For an implementation that provides for discretionary reattachment of an auto-partioned interface, each alteration of an instance of this object to the value notPartitioned(2) has the effect of reattaching the associated interface to the medium. For an implementation that does not provide for discretionary reattachment, alterations to an instance of this object are rejected according to the mechanisms of the management protocol in use. In particular, alterations to the value partitioned(1) are always so rejected. For example, such an implementation may represent its rejection of such alterations by the genErr error-status value of the SNMP. Note: this variable might be relocated to a group associated with physical media attibutes. Until such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 6 } dot3XRxAutoPartitionLog OBJECT-TYPE SYNTAX Counter ACCESS read-only J. Cook (editor) [Page 18] Internet Draft ETHERNET-LIKE OBJECTS September 1990 STATUS mandatory DESCRIPTION "The number of times that the value of the corresponding instance of the dot3XRxAutoPartitionStatus object has changed from the value notPartitioned(2) to the value partitioned(1). Note: this variable might be relocated to a group associated with physical media attibutes. Until such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 7 } dot3XRxLastSourceAddress OBJECT-TYPE SYNTAX OCTET STRING ACCESS read-only STATUS mandatory DESCRIPTION "The value of the source address field of the last MAC frame successfully received on a particular interface. This value is either 16 or 48 bits in length. Note: this variable might be relocated to a group associated with physical media attibutes. Until such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 8 } dot3XRxSourceAddressLog OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of times that the value of the corresponding instance of the dot3XRxLastSourceAddress object has changed from one value to another, distinct value. A value of one indicates that there is only one active station on the interface specified. Note: this variable might be relocated to a group associated with physical media attibutes. Until J. Cook (editor) [Page 19] Internet Draft ETHERNET-LIKE OBJECTS September 1990 such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 9 } dot3XRxLastErrorAddress OBJECT-TYPE SYNTAX OCTET STRING ACCESS read-only STATUS mandatory DESCRIPTION "The value of the source address field of the last MAC frame received with errors on a particular interface. This value is either 16 or 48 bits in length. Note: this variable might be relocated to a group associated with physical media attibutes. Until such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 10 } dot3XRxErrorAddressLog OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of times that the value of the corresponding instance of the dot3XRxLastErrorAddress object has changed from one value to another, distinct value. Note: this variable might be relocated to a group associated with physical media attibutes. Until such a group is defined, it is defined here for experimentation." ::= { dot3XRxEntry 11 } J. Cook (editor) [Page 20] Internet Draft ETHERNET-LIKE OBJECTS September 1990 -- the Ethernet-like Extended Transmit group -- Implementation of this group is optional; it is -- appropriate for all systems which the necessary metering -- is feasible. dot3XTxTable OBJECT-TYPE SYNTAX SEQUENCE OF Dot3XTxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Transmit errors and statistics for a collection of ethernet-like interfaces attached to a particular system." ::= { dot3 4 } dot3XTxEntry OBJECT-TYPE SYNTAX Dot3XTxEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "Receive errors and statistics for a particular interface to an ethernet-like medium." INDEX { dot3XTxIndex } ::= { dot3XTxTable 1 } Dot3XTxEntry ::= SEQUENCE { dot3XTxIndex INTEGER, dot3XTxEnabled INTEGER, dot3XTxDeferredTransmissions Counter, dot3XTxLateCollisions Counter, dot3XTxExcessiveCollisions Counter, dot3XTxInternalMACErrors Counter, dot3XTxCarrierSenseErrors Counter, dot3XTxExcessiveDeferrals Counter, dot3XTxTDR J. Cook (editor) [Page 21] Internet Draft ETHERNET-LIKE OBJECTS September 1990 Gauge } dot3XTxIndex OBJECT-TYPE SYNTAX INTEGER ACCESS read-only STATUS mandatory DESCRIPTION "An index value that uniquely identifies an interface to an ethernet-like medium. The interface identified by a particular value of this index is the same interface as identified by the same value of ifIndex." ::= { dot3XTxEntry 1 } dot3XTxEnabled OBJECT-TYPE SYNTAX INTEGER { true(1), false(2) } ACCESS read-write STATUS mandatory DESCRIPTION "The transmit layer management state variable (transmitEnabled as defined in [9]) for a particular interface. The value true(1) signifies that the MAC frame transmission is enabled on said interface. The value false(1) signifies that the MAC frame transmission is inhibited on said interface. In particular, the value of an instance of this object is false(2) whenever the value of the corresponding instance of the dot3MACSubLayerStatus object is disabled(2). Each alteration of an instance of this object to the value true(1) is analogous to an invocation of the enableTransmit action defined in [9] and has the effect of enabling MAC sublayer frame transmission on the associated interface. In particular, such an alteration has the effect of setting the transmit layer management state variable (transmitEnabled in [9]) for said interface to be true. Each alteration of an instance of this object to the value false(2) is analogous to an invocation of the disableTransmit action defined in [9] and has the effect of inhibiting MAC sublayer frame J. Cook (editor) [Page 22] Internet Draft ETHERNET-LIKE OBJECTS September 1990 transmission on the associated interface. In particular, such an alteration has the effect of setting the transmit layer management state variable (transmitEnabled in [9]) for said interface to be false. Any transmissions in progress are completed before transmission is inhibited." ::= { dot3XTxEntry 2 } dot3XTxDeferredTransmissions OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames for which the first transmission attempt on a particular interface is delayed because the medium is busy. The count represented by an instance of this object does not include frames involved in collisions." ::= { dot3XTxEntry 3 } dot3XTxLateCollisions OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of times that a collision is detected on a particular interface later than 512 bit-times into the transmission of a packet. Five hundred and twelve bit-times corresponds to 51.2 microseconds on a 10 Mbit/s system. A (late) collision included in a count represented by an instance of this object is also considered as a (generic) collision for purposes of other collision-related statistics." ::= { dot3XTxEntry 4 } dot3XTxExcessiveCollisions OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION J. Cook (editor) [Page 23] Internet Draft ETHERNET-LIKE OBJECTS September 1990 "A count of frames for which transmission on a particular interface fails due to excessive collisions." ::= { dot3XTxEntry 5 } dot3XTxInternalMACTransmitErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames for which transmission on a particular interface fails due to an internal MAC sublayer transmit error. A frame counted by an instance of this object is not counted by the corresponding instance of either the dot3XTxLateCollisions object, the dot3XTxExcessiveCollisions object, the dot3XTxCarrierSenseErrors object, or the dot3XTxExcessiveDeferrals object. The precise meaning of the count represented by an instance of this object is implementation- specific. In particular, an instance of this object may represent a count of transmission errors on a particular interface that are not otherwise counted." ::= { dot3XTxEntry 6 } dot3XTxCarrierSenseErrors OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of times that the carrier sense condition was lost or never asserted when attempting to transmit a frame on a particular interface. The count represented by an instance of this object is incremented at most once per transmission attempt, even if the carrier sense condition fluctuates during a transmission attempt." ::= { dot3XTxEntry 7 } J. Cook (editor) [Page 24] Internet Draft ETHERNET-LIKE OBJECTS September 1990 dot3XTxExcessiveDeferrals OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of frames for which transmission on a particular interface is deferred for an excessive period of time." ::= { dot3XTxEntry 8 } dot3XTxTDR OBJECT-TYPE SYNTAX Gauge ACCESS read-only STATUS mandatory DESCRIPTION "The result of the most recent time-domain reflectometry (TDR) measurement for a particular interface. An instance of this object represents the length of time between the most recent TDR test transmission and the detection of a collision for said transmission at said interface. This measurement is represented in units of 100 nanoseconds, regardless of the measurement granularity realized by the implementation. The value of an instance of this object is zero whenever results from a previous TDR measurement may be unavailable. The value of an instance of this object may be continually adjusted by an implementation that provides for automatic, periodic TDR measurements. For an implementation that provides for discretionary initiation of TDR measurements, each alteration of an instance of this object to any syntactically correct value (even if identical to its current value) has the effect of initiating a TDR test transmission on the associated interface. For an implementation that does not provide for discretionary TDR measurements, alterations to an instance of this object are rejected according to the mechanisms of the management protocol in use. For example, such an implementation may represent its rejection of such alterations by the genErr J. Cook (editor) [Page 25] Internet Draft ETHERNET-LIKE OBJECTS September 1990 error-status value of the SNMP. Additional control in the solicitation of a TDR measurement may be provided in the future through use of objects defined in the ifExtensions MIB." ::= { dot3XTxEntry 9 } J. Cook (editor) [Page 26] Internet Draft ETHERNET-LIKE OBJECTS September 1990 -- the Ethernet-like Collision Statistics group -- Implementation of this group is optional; it is -- appropriate for all systems which the necessary metering -- is feasible. dot3CollTable OBJECT-TYPE SYNTAX SEQUENCE OF Dot3CollEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "A collection of collision histograms for a particular set of interfaces." ::= { dot3 5 } dot3CollEntry OBJECT-TYPE SYNTAX Dot3CollEntry ACCESS not-accessible STATUS mandatory DESCRIPTION "A cell in the histogram of per-frame collisions for a particular interface. An instance of this object represents the frequency of individual MAC frames for which the transmission (successful or otherwise) on a particular interface is accompanied by a particular number of media collisions." INDEX { dot3CollIndex, dot3CollCount } ::= { dot3CollTable 1 } Dot3CollEntry ::= SEQUENCE { dot3CollIndex INTEGER, dot3CollCount INTEGER (1..16), dot3CollFrequency Counter } dot3CollIndex OBJECT-TYPE SYNTAX INTEGER ACCESS read-only STATUS mandatory DESCRIPTION J. Cook (editor) [Page 27] Internet Draft ETHERNET-LIKE OBJECTS September 1990 "The index value that uniquely identifies the interface to which a particular collision histogram cell pertains. The interface identified by a particular value of this index is the same interface as identified by the same value of ifIndex." ::= { dot3CollEntry 1 } dot3CollCount OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "The number of per-frame media collisions for which a particular collision histogram cell represents the frequency on a particular interface." ::= { dot3CollEntry 2 } dot3CollFrequency OBJECT-TYPE SYNTAX Counter ACCESS read-only STATUS mandatory DESCRIPTION "A count of individual MAC frames for which the transmission (successful or otherwise) on a particular interface is accompanied by a particular number of media collisions." ::= { dot3CollEntry 3 } END J. Cook (editor) [Page 28] Internet Draft ETHERNET-LIKE OBJECTS September 1990 7. Acknowledgements This document was produced by the Transmission MIB Working Group. This document is based almost entirely on a document written by Frank Kastenholz of Interlan entitled IEEE 802.3 Layer Management Draft M compatible MIB for TCP/IP Networks [10]. This document has been modestly reworked, initially by the SNMP Working Group, and then by the Transmission Working Group, to reflect the current conventions for defining objects for MIB interfaces. James Davin, of the MIT Laboratory for Computer Science, contributed to later drafts of this memo. J. Cook (editor) [Page 29] Internet Draft ETHERNET-LIKE OBJECTS September 1990 8. References [1] V. Cerf, IAB Recommendations for the Development of Internet Network Management Standards. Internet Working Group Request for Comments 1052. Network Information Center, SRI International, Menlo Park, California, (April, 1988). [2] V. Cerf, Report of the Second Ad Hoc Network Management Review Group, Internet Working Group Request for Comments 1109. Network Information Center, SRI International, Menlo Park, California, (August, 1989). [3] M.T. Rose (editor), Management Information Base for Network Management of TCP/IP-based internets, Internet Working Group Request for Comments 1158. Network Information Center, SRI International, Menlo Park, California, (May, 1990). [4] M.T. Rose and K. McCloghrie, Structure and Identification of Management Information for TCP/IP-based internets, Internet Working Group Request for Comments 1155. Network Information Center, SRI International, Menlo Park, California, (May, 1990). [5] K. McCloghrie and M.T. Rose, Management Information Base for Network Management of TCP/IP-based internets, Internet Working Group Request for Comments 1156. Network Information Center, SRI International, Menlo Park, California, (May, 1990). [6] J.D. Case, M.S. Fedor, M.L. Schoffstall, and J.R. Davin, Simple Network Management Protocol, Internet Working Group Request for Comments 1157. Network Information Center, SRI International, Menlo Park, California, (May, 1990). [7] Information processing systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1), International Organization for Standardization. International Standard 8824, (December, 1987). [8] Information processing systems - Open Systems Interconnection - Specification of Basic Encoding Rules J. Cook (editor) [Page 30] Internet Draft ETHERNET-LIKE OBJECTS September 1990 for Abstract Notation One (ASN.1), International Organization for Standardization. International Standard 8825, (December, 1987). [9] IEEE, IEEE 802.3 Layer Management, (November, 1988). [10] F. Kastenholz, IEEE 802.3 Layer Management Draft M compatible MIB for TCP/IP Networks, electronic mail message to mib-wg@nnsc.nsf.net, (June 9, 1989). [11] K. McCloghrie, Extensions to the Generic-Interface MIB, RFC draft. SNMP Working Group (in preparation). [12] IEEE. Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications. ANSI/IEEE Std 802.3-1985. [13] M.T. Rose, K. McCloghrie (editors), Towards Concise MIB Definitions, Internet Draft, Internet Engineering Task Force, (September, 1990). [14] M.T. Rose (editor), A Convention for Defining Traps for use with the SNMP, Internet Draft, Internet Engineering Task Force, (September, 1990). J. Cook (editor) [Page 31] Internet Draft ETHERNET-LIKE OBJECTS September 1990 Table of Contents 1 Status of this Memo ................................... 1 2 Abstract .............................................. 1 3 Historical Perspective ................................ 2 4 Objects ............................................... 4 4.1 Format of Definitions ............................... 4 5 Overview .............................................. 5 6 Definitions ........................................... 6 6.1 The Generic Ethernet-like Group ..................... 7 6.2 The Ethernet-like Transmit Group .................... 12 6.3 The Ethernet-like Extended Receive Group ............ 15 6.4 The Ethernet-Like Extended Transmit Group ........... 21 6.5 The Ethernet-like Collision Statistics Group ........ 27 7 Acknowledgements ...................................... 29 8 References ............................................ 30 J. Cook (editor) [Page 32] ------- End of Forwarded Message