Definitions of Managed Objects for RS-232-like Hardware Devices using SMIv2

Network Working Group                                         B. Stewart
Request for Comments: 1659                                  Xyplex, Inc.
Obsoletes: 1317                                                July 1994
Category: Standards Track


    Definitions of Managed Objects for RS-232-like Hardware Devices
                              using SMIv2

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Table of Contents

   1. Introduction ................................................    1
   2. The SNMPv2 Network Management Framework .....................    1
   2.1 Object Definitions .........................................    2
   3. Overview ....................................................    2
   3.1 Relationship to Interface MIB ..............................    3
   4. Definitions .................................................    3
   5. Acknowledgements ............................................   20
   6. References ..................................................   20
   7. Security Considerations .....................................   21
   8. Author's Address ............................................   21

1.  Introduction

   This memo defines an extension to the Management Information Base
   (MIB) for use with network management protocols in the Internet
   community.  In particular, it defines objects for the management of
   RS-232-like devices.

2.  The SNMPv2 Network Management Framework

   The SNMPv2 Network Management Framework consists of four major
   components.  They are:

      o    RFC 1442 [1] which defines the SMI, the mechanisms used for
           describing and naming objects for the purpose of management.

      o    STD 17, RFC 1213 [2] defines MIB-II, the core set of managed
           objects for the Internet suite of protocols.

      o    RFC 1445 [3] which defines the administrative and other
           architectural aspects of the framework.

      o    RFC 1448 [4] which defines the protocol used for network
           access to managed objects.

   The Framework permits new objects to be defined for the purpose of
   experimentation and evaluation.

2.1.  Object Definitions

   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)
   defined in the SMI.  In particular, each object object type is named
   by an OBJECT IDENTIFIER, an administratively assigned name.  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 descriptor, to
   refer to the object type.

3.  Overview

   The RS-232-like Hardware Device MIB applies to interface ports that
   might logically support the Interface MIB, a Transmission MIB, or the
   Character MIB.  The most common example is an RS-232 port with modem
   signals.

   The RS-232-like Hardware Device MIB is mandatory for all systems that
   have such a hardware port supporting services managed through some
   other MIB.

   The MIB includes multiple similar types of hardware, and as a result
   contains objects not applicable to all of those types.  The
   compliance definitions herein thus have a general group for all
   implementations, and separate groups for the different types of
   ports, such as asynchronous and synchronous.

   The RS-232-like Hardware Port MIB includes RS-232, RS-422, RS-423,
   V.35, and other asynchronous or synchronous, serial physical links
   with a similar set of control signals.

   The MIB contains objects that relate to physical layer connections.
   Such connections may provide interesting hardware signals (other than
   for basic data transfer), such as RNG and DCD.  Hardware ports also
   have such attributes as speed and bits per character.

   The MIB comprises one base object and four tables, detailed in the
   following sections.  The tables contain objects for all ports,
   asynchronous ports, and input and output control signals.

3.1.  Relationship to Interface MIB

   The RS-232-like MIB is one of many MIBs designed for layered use as
   described in the Interface MIB [5].  In most implementations where it
   is present, it will be in the lowest interface sublayer, that is, the
   RS-232-like MIB represents the physical layer, providing service to
   higher layers such as the Character MIB [6] or PPP MIB [7].

   The Interface MIB's ifTestTable and ifRcvAddressTable are not
   relevant to the RS-232-like MIB.

   The RS-232-like MIB is relevant for ifType values rs232(33), v35(45),
   and perhaps others.

   The RS-232-like MIB requires the conformance groups ifGeneralGroup,
   and ifFixedLengthGroup.

   The value of ifSpeed is the same as rs232PortOutSpeed.

   Usefulness of error counters in this MIB depends on the octet
   counters in ifFixedLengthGroup.

4.  Definitions

   RS-232-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
       Counter32, Integer32
           FROM SNMPv2-SMI
       InterfaceIndex
           FROM IF-MIB
       transmission
           FROM RFC1213-MIB
       MODULE-COMPLIANCE, OBJECT-GROUP
           FROM SNMPv2-CONF;


   rs232 MODULE-IDENTITY
       LAST-UPDATED "9405261700Z"
       ORGANIZATION "IETF Character MIB Working Group"
       CONTACT-INFO
               "        Bob Stewart
                Postal: Xyplex, Inc.

                        295 Foster Street
                        Littleton, MA 01460

                   Tel: 508-952-4816
                   Fax: 508-952-4887
                E-mail: rlstewart@eng.xyplex.com"
       DESCRIPTION
               "The MIB module for RS-232-like hardware devices."
       ::= { transmission 33 }


   -- Generic RS-232-like information

   rs232Number OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The number of ports (regardless of their current
           state) in the RS-232-like general port table."
       ::= { rs232 1 }


   -- RS-232-like General Port Table

   rs232PortTable OBJECT-TYPE
       SYNTAX SEQUENCE OF Rs232PortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "A list of port entries.  The number of entries is
           given by the value of rs232Number."
       ::= { rs232 2 }

   rs232PortEntry OBJECT-TYPE
       SYNTAX Rs232PortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "Status and parameter values for a port."
       INDEX { rs232PortIndex }
       ::= { rs232PortTable 1 }

   Rs232PortEntry ::=
       SEQUENCE {
           rs232PortIndex
               InterfaceIndex,
           rs232PortType

               INTEGER,
           rs232PortInSigNumber
               Integer32,
           rs232PortOutSigNumber
               Integer32,
           rs232PortInSpeed
               Integer32,
           rs232PortOutSpeed
               Integer32,
           rs232PortInFlowType
               INTEGER,
           rs232PortOutFlowType
               INTEGER
       }

   rs232PortIndex OBJECT-TYPE
       SYNTAX InterfaceIndex
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The value of ifIndex for the port.  By convention
           and if possible, hardware port numbers map directly
           to external connectors.  The value for each port must
           remain constant at least from one re-initialization
           of the network management agent to the next."
       ::= { rs232PortEntry 1 }

   rs232PortType OBJECT-TYPE
       SYNTAX INTEGER { other(1), rs232(2), rs422(3),
                        rs423(4), v35(5), x21(6) }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The port's hardware type."
       ::= { rs232PortEntry 2 }

   rs232PortInSigNumber OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The number of input signals for the port in the
           input signal table (rs232PortInSigTable).  The table
           contains entries only for those signals the software
           can detect and that are useful to observe."
       ::= { rs232PortEntry 3 }

   rs232PortOutSigNumber OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The number of output signals for the port in the
           output signal table (rs232PortOutSigTable).  The
           table contains entries only for those signals the
           software can assert and that are useful to observe."
       ::= { rs232PortEntry 4 }

   rs232PortInSpeed OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's input speed in bits per second.  Note that
           non-standard values, such as 9612, are probably not allowed
           on most implementations."
       ::= { rs232PortEntry 5 }

   rs232PortOutSpeed OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's output speed in bits per second.  Note that
           non-standard values, such as 9612, are probably not allowed
           on most implementations."
       ::= { rs232PortEntry 6 }

   rs232PortInFlowType OBJECT-TYPE
       SYNTAX INTEGER { none(1), ctsRts(2), dsrDtr(3) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's type of input flow control.  'none'
           indicates no flow control at this level.
           'ctsRts' and 'dsrDtr' indicate use of the indicated
           hardware signals."
       ::= { rs232PortEntry 7 }

   rs232PortOutFlowType OBJECT-TYPE
       SYNTAX INTEGER { none(1), ctsRts(2), dsrDtr(3) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's type of output flow control.  'none'
           indicates no flow control at this level.
           'ctsRts' and 'dsrDtr' indicate use of the indicated
           hardware signals."
       ::= { rs232PortEntry 8 }


   -- RS-232-like Asynchronous Port Table

   rs232AsyncPortTable OBJECT-TYPE
       SYNTAX SEQUENCE OF Rs232AsyncPortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "A list of asynchronous port entries.  Entries need
           not exist for synchronous ports."
       ::= { rs232 3 }

   rs232AsyncPortEntry OBJECT-TYPE
       SYNTAX Rs232AsyncPortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "Status and parameter values for an asynchronous
           port."
       INDEX { rs232AsyncPortIndex }
       ::= { rs232AsyncPortTable 1 }

   Rs232AsyncPortEntry ::=
       SEQUENCE {
           rs232AsyncPortIndex
               InterfaceIndex,
           rs232AsyncPortBits
               INTEGER,
           rs232AsyncPortStopBits
               INTEGER,
           rs232AsyncPortParity
               INTEGER,
           rs232AsyncPortAutobaud
               INTEGER,
           rs232AsyncPortParityErrs
               Counter32,
           rs232AsyncPortFramingErrs
               Counter32,
           rs232AsyncPortOverrunErrs
               Counter32

       }

   rs232AsyncPortIndex OBJECT-TYPE
       SYNTAX InterfaceIndex
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "A unique value for each port.  Its value is the
           same as rs232PortIndex for the port."
       ::= { rs232AsyncPortEntry 1 }

   rs232AsyncPortBits OBJECT-TYPE
       SYNTAX INTEGER (5..8)
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's number of bits in a character."
       ::= { rs232AsyncPortEntry 2 }

   rs232AsyncPortStopBits OBJECT-TYPE
       SYNTAX INTEGER { one(1), two(2),
                        oneAndHalf(3), dynamic(4) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's number of stop bits."
       ::= { rs232AsyncPortEntry 3 }

   rs232AsyncPortParity OBJECT-TYPE
       SYNTAX INTEGER { none(1), odd(2), even(3),
                        mark(4), space(5) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The port's sense of a character parity bit."
       ::= { rs232AsyncPortEntry 4 }

   rs232AsyncPortAutobaud OBJECT-TYPE
       SYNTAX INTEGER { enabled(1), disabled(2) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "A control for the port's ability to automatically
           sense input speed.

           When rs232PortAutoBaud is 'enabled', a port may
           autobaud to values different from the set values for
           speed, parity, and character size.  As a result a
           network management system may temporarily observe
           values different from what was previously set."

       ::= { rs232AsyncPortEntry 5 }

   rs232AsyncPortParityErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of characters with a parity error,
           input from the port since system re-initialization
           and while the port state was 'up' or 'test'."
       ::= { rs232AsyncPortEntry 6 }

   rs232AsyncPortFramingErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of characters with a framing error,
           input from the port since system re-initialization
           and while the port state was 'up' or 'test'."
       ::= { rs232AsyncPortEntry 7 }

   rs232AsyncPortOverrunErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of characters with an overrun error,
           input from the port since system re-initialization
           and while the port state was 'up' or 'test'."
       ::= { rs232AsyncPortEntry 8 }


   -- RS-232-like Synchronous Port Table

   rs232SyncPortTable OBJECT-TYPE
       SYNTAX SEQUENCE OF Rs232SyncPortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "A list of asynchronous port entries.  Entries need
           not exist for synchronous ports."
       ::= { rs232 4 }

   rs232SyncPortEntry OBJECT-TYPE
       SYNTAX Rs232SyncPortEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "Status and parameter values for a synchronous
           port."
       INDEX { rs232SyncPortIndex }
       ::= { rs232SyncPortTable 1 }

   Rs232SyncPortEntry ::=
       SEQUENCE {
           rs232SyncPortIndex
               InterfaceIndex,
           rs232SyncPortClockSource
               INTEGER,
           rs232SyncPortFrameCheckErrs
               Counter32,
           rs232SyncPortTransmitUnderrunErrs
               Counter32,
           rs232SyncPortReceiveOverrunErrs
               Counter32,
           rs232SyncPortInterruptedFrames
               Counter32,
           rs232SyncPortAbortedFrames
               Counter32,
           rs232SyncPortRole
               INTEGER,
           rs232SyncPortEncoding
               INTEGER,
           rs232SyncPortRTSControl
               INTEGER,
           rs232SyncPortRTSCTSDelay
               Integer32,
           rs232SyncPortMode
               INTEGER,
           rs232SyncPortIdlePattern
               INTEGER,
           rs232SyncPortMinFlags
               Integer32
       }

   rs232SyncPortIndex OBJECT-TYPE
       SYNTAX InterfaceIndex
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "A unique value for each port.  Its value is the
           same as rs232PortIndex for the port."
       ::= { rs232SyncPortEntry 1 }

   rs232SyncPortClockSource OBJECT-TYPE
       SYNTAX INTEGER { internal(1), external(2), split(3) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "Source of the port's bit rate clock. 'split' means
           the tranmit clock is internal and the receive clock
           is external."
       ::= { rs232SyncPortEntry 2 }

   rs232SyncPortFrameCheckErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of frames with an invalid frame check
           sequence, input from the port since system
           re-initialization and while the port state was 'up'
           or 'test'."
       ::= { rs232SyncPortEntry 3 }

   rs232SyncPortTransmitUnderrunErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of frames that failed to be
           transmitted on the port since system
           re-initialization and while the port state was 'up'
           or 'test' because data was not available to the
           transmitter in time."
       ::= { rs232SyncPortEntry 4 }

   rs232SyncPortReceiveOverrunErrs OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of frames that failed to be received
           on the port since system re-initialization and while
           the port state was 'up' or 'test' because the
           receiver did not accept the data in time."
       ::= { rs232SyncPortEntry 5 }

   rs232SyncPortInterruptedFrames OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Total number of frames that failed to be received
           or transmitted on the port due to loss of modem
           signals since system re-initialization and while the
           port state was 'up' or 'test'."
       ::= { rs232SyncPortEntry 6 }

   rs232SyncPortAbortedFrames OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Number of frames aborted on the port due to
           receiving an abort sequence since system
           re-initialization and while the port state was 'up'
           or 'test'."
       ::= { rs232SyncPortEntry 7 }

   rs232SyncPortRole OBJECT-TYPE
       SYNTAX INTEGER  { dte(1), dce(2) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The role the device is playing that is using this port.
              dte    means the device is performing the role of
                     data terminal equipment
              dce    means the device is performing the role of
                     data circuit-terminating equipment."
       DEFVAL { dce }
       ::= { rs232SyncPortEntry 8 }

   rs232SyncPortEncoding OBJECT-TYPE
       SYNTAX INTEGER  { nrz(1), nrzi(2) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The bit stream encoding technique that is in effect
            for this port.
              nrz    for Non-Return to Zero encoding
              nrzi   for Non-Return to Zero Inverted encoding."
       DEFVAL { nrz }
       ::= { rs232SyncPortEntry 9 }

   rs232SyncPortRTSControl OBJECT-TYPE
       SYNTAX INTEGER  { controlled(1), constant(2) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION

           "The method used to control the Request To Send (RTS)
            signal.

              controlled  when the DTE is asserts RTS each time
                          data needs to be transmitted and drops
                          RTS at some point after data
                          transmission begins.

                          If rs232SyncPortRole is 'dte', the
                          RTS is an output signal. The device
                          will issue a RTS and wait for a CTS
                          from the DCE before starting to
                          transmit.

                          If rs232SyncPortRole is 'dce', the
                          RTS is an input signal. The device
                          will issue a CTS only after having
                          received RTS and waiting the
                          rs232SyncPortRTSCTSDelay interval.

              constant    when the DTE constantly asserts RTS."
       DEFVAL { constant }
       ::= { rs232SyncPortEntry 10 }

   rs232SyncPortRTSCTSDelay OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The interval (in milliseconds) that the DCE must wait
            after it sees RTS asserted before asserting CTS.  This
            object exists in support of older synchronous devices
            that cannot recognize CTS within a certain interval
            after it asserts RTS."
       DEFVAL { 0 }
       ::= { rs232SyncPortEntry 11 }

   rs232SyncPortMode OBJECT-TYPE
       SYNTAX INTEGER  { fdx(1), hdx(2), simplex-receive(3),
                         simplex-send(4) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The mode of operation of the port with respect to the
            direction and simultaneity of data transfer.

              fdx              when frames on the data link can be
                               transmitted and received at the same
                               time

              hdx              when frames can either be received
                               from the data link or transmitted
                               onto the data link but not at the
                               same time.

              simplex-receive  when frames can only be received on
                               this data link.

              simplex-send     when frames can only be sent on this
                               data link."
       DEFVAL { fdx }
       ::= { rs232SyncPortEntry 12 }

   rs232SyncPortIdlePattern OBJECT-TYPE
       SYNTAX INTEGER  { mark(1), space(2) }
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The bit pattern used to indicate an idle line."
       DEFVAL { space }
       ::= { rs232SyncPortEntry 13 }

   rs232SyncPortMinFlags OBJECT-TYPE
       SYNTAX Integer32
       MAX-ACCESS read-write
       STATUS current
       DESCRIPTION
           "The minimum number of flag patterns this port needs in
            order to recognize the end of one frame and the start
            of the next.  Plausible values are 1 and 2."
       DEFVAL { 2 }
       ::= { rs232SyncPortEntry 14 }


   -- Input Signal Table

   rs232InSigTable OBJECT-TYPE
       SYNTAX SEQUENCE OF Rs232InSigEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "A list of port input control signal entries
           implemented and visible to the software on the port,
           and useful to monitor."

       ::= { rs232 5 }

   rs232InSigEntry OBJECT-TYPE
       SYNTAX Rs232InSigEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "Input control signal status for a hardware port."
       INDEX { rs232InSigPortIndex, rs232InSigName }
       ::= { rs232InSigTable 1 }

   Rs232InSigEntry ::=
       SEQUENCE {
           rs232InSigPortIndex
               InterfaceIndex,
           rs232InSigName
               INTEGER,
           rs232InSigState
               INTEGER,
           rs232InSigChanges
               Counter32
       }

   rs232InSigPortIndex OBJECT-TYPE
       SYNTAX InterfaceIndex
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The value of rs232PortIndex for the port to which
           this entry belongs."
       ::= { rs232InSigEntry 1 }

   rs232InSigName OBJECT-TYPE
       SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
                        dcd(6), sq(7), srs(8), srts(9),
                        scts(10), sdcd(11) }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Identification of a hardware signal, as follows:

               rts    Request to Send
               cts    Clear to Send
               dsr    Data Set Ready
               dtr    Data Terminal Ready
               ri     Ring Indicator
               dcd    Received Line Signal Detector
               sq     Signal Quality Detector
               srs    Data Signaling Rate Selector
               srts   Secondary Request to Send
               scts   Secondary Clear to Send
               sdcd   Secondary Received Line Signal Detector
           "
       REFERENCE
           "EIA Standard RS-232-C, August 1969."
       ::= { rs232InSigEntry 2 }

   rs232InSigState OBJECT-TYPE
       SYNTAX INTEGER { none(1), on(2), off(3) }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The current signal state."
       ::= { rs232InSigEntry 3 }

   rs232InSigChanges OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The number of times the signal has changed from
           'on' to 'off' or from 'off' to 'on'."
       ::= { rs232InSigEntry 4 }


   -- Output Signal Table

   rs232OutSigTable OBJECT-TYPE
       SYNTAX SEQUENCE OF Rs232OutSigEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "A list of port output control signal entries
           implemented and visible to the software on the port,
           and useful to monitor."
       ::= { rs232 6 }

   rs232OutSigEntry OBJECT-TYPE
       SYNTAX Rs232OutSigEntry
       MAX-ACCESS not-accessible
       STATUS current
       DESCRIPTION
           "Output control signal status for a hardware port."
       INDEX { rs232OutSigPortIndex, rs232OutSigName }
       ::= { rs232OutSigTable 1 }

   Rs232OutSigEntry ::=
       SEQUENCE {
           rs232OutSigPortIndex
               InterfaceIndex,
           rs232OutSigName
               INTEGER,
           rs232OutSigState
               INTEGER,
           rs232OutSigChanges
               Counter32
       }

   rs232OutSigPortIndex OBJECT-TYPE
       SYNTAX InterfaceIndex
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The value of rs232PortIndex for the port to which
           this entry belongs."
       ::= { rs232OutSigEntry 1 }

   rs232OutSigName OBJECT-TYPE
       SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
                        dcd(6), sq(7), srs(8), srts(9),
                        scts(10), sdcd(11) }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "Identification of a hardware signal, as follows:

               rts    Request to Send
               cts    Clear to Send
               dsr    Data Set Ready
               dtr    Data Terminal Ready
               ri     Ring Indicator
               dcd    Received Line Signal Detector
               sq     Signal Quality Detector
               srs    Data Signaling Rate Selector
               srts   Secondary Request to Send
               scts   Secondary Clear to Send
               sdcd   Secondary Received Line Signal Detector
           "
       REFERENCE
           "EIA Standard RS-232-C, August 1969."
       ::= { rs232OutSigEntry 2 }

   rs232OutSigState OBJECT-TYPE
       SYNTAX INTEGER { none(1), on(2), off(3) }
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The current signal state."
       ::= { rs232OutSigEntry 3 }

   rs232OutSigChanges OBJECT-TYPE
       SYNTAX Counter32
       MAX-ACCESS read-only
       STATUS current
       DESCRIPTION
           "The number of times the signal has changed from
           'on' to 'off' or from 'off' to 'on'."
       ::= { rs232OutSigEntry 4 }


   -- conformance information

   rs232Conformance OBJECT IDENTIFIER ::= { rs232 7 }

   rs232Groups      OBJECT IDENTIFIER ::= { rs232Conformance 1 }
   rs232Compliances OBJECT IDENTIFIER ::= { rs232Conformance 2 }


   -- compliance statements

   rs232Compliance MODULE-COMPLIANCE
       STATUS  current
       DESCRIPTION
               "The compliance statement for SNMPv2 entities
               which have RS-232-like hardware interfaces."

       MODULE  -- this module
           MANDATORY-GROUPS { rs232Group }

           GROUP   rs232AsyncGroup
           DESCRIPTION
               "The Asynch group is mandatory only for those
                SNMPv2 entities which have asynchronous
                interfaces Rs-232-like."

           GROUP   rs232SyncGroup
           DESCRIPTION
               "The Synch group is mandatory only for those
                SNMPv2 entities which have synchronous
                interfaces Rs-232-like."
       ::= { rs232Compliances 1 }

   -- units of conformance

   rs232Group    OBJECT-GROUP
       OBJECTS { rs232Number, rs232PortIndex, rs232PortType,
                 rs232PortInSigNumber, rs232PortOutSigNumber,
                 rs232PortInSpeed, rs232PortOutSpeed,
                 rs232PortInFlowType, rs232PortOutFlowType,
                 rs232InSigPortIndex, rs232InSigName,
                 rs232InSigState, rs232InSigChanges,
                 rs232OutSigPortIndex, rs232OutSigName,
                 rs232OutSigState, rs232OutSigChanges }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
                applicable to all RS-232-like interfaces."
       ::= { rs232Groups 1 }

   rs232AsyncGroup OBJECT-GROUP
       OBJECTS { rs232AsyncPortIndex, rs232AsyncPortBits,
                 rs232AsyncPortStopBits, rs232AsyncPortParity,
                 rs232AsyncPortAutobaud, rs232AsyncPortParityErrs,
                 rs232AsyncPortFramingErrs, rs232AsyncPortOverrunErrs }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
                applicable to asynchronous RS-232-like interfaces."
       ::= { rs232Groups 2 }

   rs232SyncGroup OBJECT-GROUP
       OBJECTS { rs232SyncPortIndex, rs232SyncPortClockSource,
                 rs232SyncPortFrameCheckErrs,
                 rs232SyncPortTransmitUnderrunErrs,
                 rs232SyncPortReceiveOverrunErrs,
                 rs232SyncPortInterruptedFrames,
                 rs232SyncPortAbortedFrames }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
                applicable to synchronous RS-232-like interfaces."
       ::= { rs232Groups 3 }

   rs232SyncSDLCGroup OBJECT-GROUP
       OBJECTS { rs232SyncPortRole,
                 rs232SyncPortEncoding,
                 rs232SyncPortRTSControl,
                 rs232SyncPortRTSCTSDelay,
                 rs232SyncPortMode,
                 rs232SyncPortIdlePattern,
                 rs232SyncPortMinFlags }
       STATUS  current
       DESCRIPTION
               "A collection of objects providing information
                applicable to synchronous RS-232-like interfaces
                running SDLC."
       ::= { rs232Groups 4 }

   END

5.  Acknowledgements

   This memo was produced by the IETF Character MIB Working Group.

6.  References

   [1] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Structure
       of Management Information for version 2 of the Simple Network
       Management Protocol (SNMPv2)", RFC 1442, SNMP Research,Inc.,
       Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [2] McCloghrie, K., and M. Rose, Editors, "Management Information
       Base for Network Management of TCP/IP-based internets: MIB-II",
       STD 17, RFC 1213, Hughes LAN Systems, Performance Systems
       International, March 1991.

   [3] Galvin, J., and K. McCloghrie, "Administrative Model for version
       2 of the Simple Network Management Protocol (SNMPv2)", RFC 1445,
       Trusted Information Systems, Hughes LAN Systems, April 1993.

   [4] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
       Operations for version 2 of the Simple Network Management
       Protocol (SNMPv2)", RFC 1448, SNMP Research,Inc., Hughes LAN
       Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

   [5] McCloghrie, K., and F. Kastenholz, "Evolution of the Interfaces
       Group of MIB-II", RFC 1573, Hughes LAN Systems, FTP Software,
       January 1994.

   [6] Stewart, B., "Definitions of Managed Objects for Character Stream
       Devices using SMIv2", RFC 1658, Xyplex, Inc., July 1994.

   [7] Kastenholz, F., "The Definitions of Managed Objects for the Link
       Control Protocol of the Point-to-Point Protocol", RFC 1471, FTP
       Software, Inc., June 1993.

7.  Security Considerations

   Security issues are not discussed in this memo.

8.  Author's Address

   Bob Stewart
   Xyplex, Inc.
   295 Foster Street
   Littleton, MA 01460

   Phone: 508-952-4816
   Fax: 508-952-4887
   EMail: rlstewart@eng.xyplex.com