o  checksum failure

    Generated each time a checksum validation fails on a received
    TPDU.

 o  invalid tpdu received

    Generated when a TPDU received from the remote NSAP is in
    violation of the OSI transport protocol. If the error occurred
    during connection establishment, a DR (disconnect request) TPDU
    will be sent in response to the protocol error. If the error
    occurred on an established transport connection, an ER (error)
    TPDU will be sent in response to the protocol error. The remote
    protocol error counter will be incremented.   Arguments:

    reject     If an ER TPDU was transmitted or received, this is
    cause      the value of the reject cause parameter. If a DR was
               transmitted, this is the value of the reason parameter.

    erroneous  The portion of the invalid TPDU transmitted or received
    trans-     in the invalid TPDU parameter of the ER or DR TPDU.
    port PDU   (OpenVMS only)

    DNA        The unique error number used to unambiguously
    error      distinguish between different errors. This number is
               completely independent of the reason and reject cause
               values defined by the OSI Transport protocol, the set
               of which is too sparse to provide useful information.

 o  er tpdu received

    Generated whenever an ER (error) TPDU is received from the remote
    NSAP. The local protocol error counter will be incremented.
    Arguments:

    reject     The value of the reject cause parameter in the received
    cause      ER TPDU.

    erroneous  The portion of the invalid TPDU received in the invalid
    trans-     TPDU parameter of the ER TPDU.
    port PDU

    DNA        The unique error number used to unambiguously
    error      distinguish between different errors. This number is
               completely independent of the reason and reject cause
               values defined by the OSI Transport protocol, the set
               of which is too sparse to provide useful information.
      	      (OpenVMS only)

 o  local transport disconnection

    Generated each time a connection attempt initiated by the remote
    NSAP is rejected by the local NSAP. This does not include rejects
    generated by the local user of the transport service. Thus, this
    event is generated on the transmission of a DR TPDU in which
    the reason parameter has a value other than 128. The reject sent
    counter will be incremented.   Argument:

    DNA error      This is the value transmitted in the additional
                   information parameter of the DR TPDU.

 o  remote transport disconnection

    This event is generated each time a connection attempt initiated
    from the local NSAP is rejected by the remote NSAP. This does
    not include rejects requested by the remote user of the transport
    service. Thus, this event is generated on the receipt of a DR
    TPDU in which the reason parameter has a value other than 128
    (which is a normal disconnect). The reject received counter will
    be incremented.  Arguments:

    reason      Reason why the event was generated and it is the
                value received in the reason parameter of the DR
                TPDU.

    additional  The value received in the additional information
    informa-    parameter of the DR TPDU. If the remote NSAP is a
    tion        DNA OSI Transport implementation, the additional
                information parameter will have one of the following
                values:

                '01'H        Too much user data in CR (connection
                             request) or CC (connection confirm) TPDU
                '02'H        Proposed TPDU size invalid
                '05'H        Invalid protocol class requested
                '07'H        Illegal negotiation attempted
                '08'H        Invalid parameter in TPDU
                '09'H        TPDU header length invalid
                '0A'H        Parameter length error in TPDU header
                '0B'H        TPDU longer than negotiated maximum
                '0C'H        Segmentation of expedited data illegal
                '0D'H        Invalid parameter value
                '10'H        Invalid TPDU type
                '12'H        Expedited data out of sequence
                '40'H        Unknown transport selector
                '41'H        Proposed protocol class(es) unavailable
                '42'H        Insufficient resources
                '43'H        Maximum connections already active
                '80'H        Unknown reference
                '81'H        Connection timed out
                '82'H        Idle connection timed out
                '83'H        Unacknowledged ER TPDU