NET$MGMT_HELP.HLB  —  csmacd  station
   A CSMA-CD station entity manages a CSMA/CD controller. Wherever Phase IV
   DECnet manages a line, DECnet-Plus manages a station. Each station corresponds
   to a particular logical link control LLC, medium access control MAC, and
   physical attachment.  The station name refers to the station managed by this
   command.

1  –  character

     STATION BUFFERS

         Number of receive buffers reserved for the station. You can modify
         this characteristic only when the entity is disabled.

2  –  counters

   Unless stated otherwise, counts include both normal and multicast traffic and
   all protocol types, service access points SAPs, and protocol identifiers.

     ALIGNMENT ERRORS

         Number of times a received frame did not contain an integral number of
         octets.

     CARRIER CHECK FAILURES

         Number of times the data link did not sense the receive carrier signal
         or detected an error in the receive carrier signal during transmission
         of a frame.

     COLLISION DETECT CHECK FAILURES

         Number of times the collision detect test signal was not sensed after
         a transmission. If this count approximates the number of frames sent,
         either the collision detect circuitry is not working correctly or the
         test signal is not implemented.

     DATA OVERRUNS

         Number of times the hardware lost one or more consecutive, partially
         complete, incoming frames because it could not keep up with the
         incoming frame rate. Used in conjunction with pdus received, this
         count provides a measure of hardware resource and bandwidth failures.

     EXCESSIVE COLLISIONS

         Number of times a transmission failed because the maximum allowable
         number of retransmission attempts all culminated in collisions.

     FRAME CHECK ERRORS

         Number of times a received frame containing an integral number of
         octets failed the frame check sequence FCS.

     FRAME SIZE ERRORS

         Number of times the user requested transmission of a frame outside the
         range of valid frame sizes.

     FRAMES TOO LONG

         Number of times a received frame exceeded the maximum length allowed
         by CSMA/CD medium access control.

     INITIALLY DEFERRED PDUS SENT

         Number of times a PDU was deferred by the station access algorithm on
         the first attempt at transmission, but was then transmitted
         successfully without collision. Used in conjunction with PDUs sent,
         this count measures the rate of CSMA/CD contention with no collisions.

     LATE COLLISIONS

         Number of times a collision was detected after the allotted time for
         collisions had expired.

     MULTICAST OCTETS RECEIVED

         Number of multicast data octets that were successfully received. The
         count is the number of octets in the CSMA/CD user data field and does
         not include MAC headers. Comparing this count to the octets received
         count yields the gross percentage of bandwidth that was consumed over
         time by multicast frames received by the local system.

     MULTICAST OCTETS SENT

         Number of multicast data octets that were successfully sent. The count
         is the number of octets in the MAC user data field, including any
         padding or length fields; it does not include MAC headers. Comparing
         this count to the octets sent count yields the gross percentage of
         bandwidth that was consumed over time by multicast frames
         transmitted by the local system.

     MULTICAST PDUS RECEIVED

         Number of multicast PDUs that were successfully received. Comparing
         this count to the pdus received count yields a gross percentage of
         CSMA/CD usage for multicast PDUs received by this system.

     MULTICAST PDUS SENT

         Number of multicast PDUs that were successfully sent. Comparing this
         count to the pdus sent count yields a gross percentage of CSMA/CD
         usage for multicast PDUs sent by this system.

     MULTIPLE COLLISIONS PDUS SENT

         Number of times a PDU was successfully transmitted on the third or
         later attempt by the station access algorithm after normal collisions
         on previous attempts. Used in conjunction with pdus sent, this count
         provides a measure of CSMA/CD media contention at a level where there
         are collisions and the backoff algorithm no longer works efficiently.

     OCTETS RECEIVED

         Total number of MAC user data octets that were successfully received
         from frames that passed address and protocol filtering for both
         individual and multicast MAC addresses. The count is the number of
         octets in the CSMA/CD user data field plus any padding, Ethernet
         length fields, or LLC header fields; it does not include MAC
         headers. Adding the octets received count to the protocol overhead
         calculated from the pdus received count yields the amount of CSMA/CD
         bandwidth consumed by frames received by the local system.

     OCTETS SENT

         Total number of user data octets that were successfully sent. The
         count is the number of octets in the MAC user data field including any
         padding or length fields; it does not include MAC headers. Adding the
         octets sent count to the protocol overhead calculated from the pdus
         sent count yields the amount of CSMA/CD bandwidth consumed over time
         by frames sent by the local system.

     PDUS RECEIVED

         Total number of PDUs that passed address and protocol filtering and
         were received without errors. The count provides a gross measurement
         of incoming CSMA/CD usage by the local system; this information can be
         used in conjunction with other counters to approximate the average
         receive frame size or to determine the ratio of errors to successful
         receives.

     PDUS SENT

         Total number of PDUs successfully sent.  The count provides a gross
         measurement of outgoing CSMA/CD usage by the local system; this
         information can be used in conjunction with other counters to
         approximate the average transmit frame size or to determine the ratio
         of errors to successful transmissions.

     RECEIVE DATA LENGTH ERRORS

         Number of times a frame was received with a length field value that was
         invalid for the number of octets actually received by medium access
         control.

     SEND DATA LENGTH ERRORS

         Number of times the user requested transmission of an 802.3 frame with
         a length field value that was not valid for the number of octets
         actually passed.

     SINGLE COLLISION PDUS SENT

         Number of times a PDU was successfully transmitted on the second
         attempt by the station access algorithm after a normal collision
         occurred on the first attempt. Used in conjunction with pdus sent,
         this count provides a measure of CSMA/CD media contention at a level
         where there are collisions, but the backoff algorithm still works
         efficiently.

     STATION FAILURES

         Number of times that the station self-testing procedures reported
         failure.

     UNAVAILABLE STATION BUFFERS

         Number of times a complete, fully received PDU was discarded because
         no station buffer was available. Used with pdus received, this count
         provides a measure of receive problems related to the station buffer.

     UNAVAILABLE USER BUFFERS

         Number of times no user buffer was available for an incoming frame that
         passed all filtering for the port. Used in conjunction with the pdus
         received count, this counter can indicate the rate of user buffer
         receive problems.

     UNRECOGNIZED INDIVIDUAL DESTINATION PDUS

         Number of times a received PDU with an individual destination MAC
         address was discarded because there was no port with the correct
         Ethernet protocol type, SNAP protocol identifier, or link logical
         control SAP address enabled.

     UNRECOGNIZED MULTICAST DESTINATION PDUS

         Number of times a received PDU with a multicast destination MAC
         address was discarded because there was no port with the correct
         Ethernet protocol type, SNAP protocol identifier, or link logical
         control SAP address enabled.

3  –  status

     ADDRESS FILTERS

         All individual MAC addresses currently enabled by any of the ports on
         the station.

     COMMUNICATION PORT

         DECnet-Plus device name for the station.

     HARDWARE ADDRESS

         Individual medium access control MAC address that was assigned during
         manufacture of the communications hardware that is associated with the
         station.

     MAC ADDRESS

         Current MAC address if any of the station. For more information about
         the MAC address, refer to the enable command.

     RECEIVE MODE

         Current receive mode for the station.  Some stations may not support
         all modes.

         NORMAL -        The station receives only those frames individual and
                         multicast that meet the normal format, protocol, and
                         access control requirements.

         ALL MULTICAST - The station receives all individual-addressed frames
                         that meet the normal format, protocol, and address
                         requirements, and all multicast-addressed frames
                         regardless of their format, protocol, and address
                         types.

         PROMISCUOUS -   The station receives all frames individual and
                         multicast regardless of format, Ethernet protocol
                         type, SNAP identifier, LLC SAP address, or MAC
                         address.

     STATE

         Operational state of the station.

         OFF -           The station is disabled.

         ON -            The station is enabled and available for use.

         FAILED -        Either an attempt to enable the station failed during
                         the self-test or the station was on and the data link
                         determined that the station would now fail the
                         self-test.

         INITIALIZING -  The station is currently being initialized and tested
                         by the data link.
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