rfc2889.txt

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5.2  Partially meshed one-to-many/many-to-one

5.2.1 Objective

   To determine the throughput when transmitting from/to multiple ports
   and to/from one port. As with the fully meshed throughput test, this
   test is a measure of the capability of the DUT to switch frames
   without frame loss.  Results of this test can be used to determine
   the ability of the DUT to utilize an Ethernet port when switching
   traffic from multiple Ethernet ports.

5.2.2 Setup Parameters

   When offering bursty meshed traffic, the following parameters MUST be
   defined.  Each parameter is configured with the following
   considerations.

      Frame Size - Recommended frame sizes are 64, 128, 256, 512, 1024,
      1280 and 1518 bytes, per RFC 2544 section 9 [3].  The four CRC
      bytes are included in the frame size specified.

      Traffic Direction - Traffic can be generated in one direction, the
      reverse direction, or both directions.

      Interframe Gap (IFG) - The IFG between frames inside a burst MUST
      be at the minimum specified by the standard (9.6 us for 10Mbps
      Ethernet, 960 ns for 100Mbps Ethernet, and 96 ns for 1 Gbps
      Ethernet) of the medium being tested.

      Duplex mode - Half duplex or full duplex.

      ILoad - Intended Load per port is expressed in a percentage of the
      medium's maximum theoretical load, regardless of traffic
      orientation or duplex mode.  Certain test configurations will
      theoretically over-subscribe the DUT/SUT.

      In half duplex bidirectional traffic, an ILoad over 50% will
      over-subscribe the DUT/SUT.

      Burst Size - The burst size defines the number of frames sent
      back-to-back at the minimum legal IFG [4] before pausing
      transmission to receive frames.  Burst sizes SHOULD vary between 1
      and 930 frames.  A burst size of 1 will simulate constant load
      [1].







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      Addresses per port - Represents the number of addresses which are
      being tested for each port.  Number of addresses SHOULD be a
      binary exponential (i.e. 1, 2, 4, 8, 16, 32, 64, 128, 256, ...).
      Recommended value is 1.

      Trial Duration - The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.

5.2.3 Procedure

   All ports on the tester MUST transmit test frames either in a Frame
   Based or Time Based mode (Appendix B).  Depending upon traffic
   direction, some or all of the ports will be transmitting.  All ports
   SHOULD start transmitting their frames within 1% of the trial
   duration.  For a trial duration of 30 seconds, all ports SHOULD have
   started transmitting frames within 300 milliseconds of each other.

   Test frames transmitted from the Many Ports MUST be destined to the
   One port.  Test frames transmitted from the One Port MUST be destined
   to the Many ports in a round robin type fashion.  See section 5.1.3
   for a description of the round robin fashion.

   For tests using multiple addresses per port, the actual port
   destinations are the same as described above and the actual
   source/destination address pairs SHOULD be chosen randomly to
   exercise the DUT/SUT's ability to perform address lookups.

        +----------+
        |          |
        |   Many   | <--------
        |          |          \
        +----------+           \
                                \
        +----------+             \               +-------------+
        |          |              ------------>  |             |
        |   Many   |  <----------------------->  |     One     |
        |          |              ------------>  |             |
        +----------+             /               +-------------+
                                /
        +----------+           /
        |          |          /
        |   Many   |  <-------
        |          |
        +----------+

   For every address, the testing device MUST send learning frames to
   allow the DUT/SUT to update its address tables properly.




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5.2.4 Measurements

   Each receiving port MUST categorize, then count the frames into one
   of two groups:

      1.) Received Frames: received frames MUST have the correct
          destination MAC address and SHOULD match a signature field.

      2.) Flood count [2].

   Any frame originating from the DUT/SUT MUST not be counted as a
   received frame.  Frames originating from the DUT/SUT MAY be counted
   as flooded frames or not counted at all.

   Forwarding rate (FR) of the DUT/SUT SHOULD be reported as the number
   of test frames per second that the device is observed to successfully
   transmit to the correct destination interface in response to a
   specified Oload.  The Oload MUST also be cited.

   Forwarding rate at maximum offered load (FRMOL) MUST be reported as
   the number of test frames per second that a device can successfully
   transmit to the correct destination interface in response to the MOL
   as defined in section 3.6 [2]. The MOL MUST also be cited.

   Maximum forwarding rate (MFR) MUST be reported as the highest
   forwarding rate of a DUT/SUT taken from an iterative set of
   forwarding rate measurements.  The iterative set of forwarding rate
   measurements are made by adjusting Iload.  The Oload applied to the
   device MUST also be cited.

5.2.5 Reporting Format

   The results for these tests SHOULD be reported in the form of a
   graph.  The x coordinate SHOULD be the frame size, the y coordinate
   SHOULD be the test results.  There SHOULD be at least two lines on
   the graph, one plotting the theoretical and one plotting the test
   results.

   To measure the DUT/SUT's ability to switch traffic while performing
   many different address lookups, the number of addresses per port MAY
   be increased in a series of tests.










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5.3 Partially meshed multiple devices

5.3.1 Objective

   To determine the throughput, frame loss and forwarding rates of two
   switching devices equipped with multiple ports and one high speed
   backbone uplink (Gigabit Ethernet, ATM, SONET).

5.3.2 Setup Parameters

   When offering bursty partially meshed traffic, the following
   parameters MUST be defined.  Each variable is configured with the
   following considerations.

      Frame Size - Recommended frame sizes are 64, 128, 256, 512, 1024,
      1280 and 1518 bytes, per RFC 2544 section 9 [3].  The four CRC
      bytes are included in the frame size specified.

      Interframe Gap (IFG) - The IFG between frames inside a burst MUST
      be at the minimum specified by the standard (9.6 us for 10Mbps
      Ethernet, 960 ns for 100Mbps Ethernet, and 96 ns for 1 Gbps
      Ethernet) of the medium being tested.

      Duplex mode - Half duplex or full duplex.

      ILoad - Intended Load per port is expressed in a percentage of the
      medium's maximum theoretical load, regardless of traffic
      orientation or duplex mode.  Certain test configurations will
      theoretically over-subscribe the DUT/SUT.

      In half duplex, an ILoad over 50% will over-subscribe the DUT/SUT.

      Burst Size - The burst size defines the number of frames sent
      back-to-back at the minimum legal IFG [4] before pausing
      transmission to receive frames.  Burst sizes SHOULD vary between 1
      and 930 frames.  A burst size of 1 will simulate constant load
      [1].

      Addresses per port - Represents the number of addresses which are
      being tested for each port.  Number of addresses SHOULD be a
      binary exponential (i.e. 1, 2, 4, 8, 16, 32, 64, 128, 256, ...).
      Recommended value is 1.

      Trial Duration - The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.






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      Local Traffic - A Boolean value of ON or OFF.  The frame sequence
      algorithm MAY be altered to remove local traffic.  With local
      traffic ON, the algorithm is exactly the same as a fully meshed
      throughput.  With local traffic OFF, the port sends frames to all
      other ports on the other side of the backbone uplink in a round
      robin type fashion.

5.3.3 Procedure

   All ports on the tester MUST transmit test frames either in a Frame
   Based or Time Based mode (Appendix B).  All ports SHOULD start
   transmitting their frames within 1% of the trial duration.  For a
   trial duration of 30 seconds, all ports SHOULD have started
   transmitting frames with 300 milliseconds of each other.

   Each port in the test MUST send test frames to all other ports in a
   round robin type fashion as defined in section 5.1.3.  Local traffic
   MAY be removed from the round robin list in order to send the entire
   load across the backbone uplink.

   For tests using multiple addresses per port, the actual port
   destinations are the same as described above and the actual
   source/destination address pairs SHOULD be chosen randomly to
   exercise the DUT/SUT's ability to perform address lookups.

   For every address, the testing device MUST send learning frames to
   allow the DUT/SUT to update its address tables properly.

   To measure the DUT/SUT's ability to switch traffic while performing
   many different address lookups, the number of addresses per port MAY
   be increased in a series of tests.

5.3.4 Measurements

   Each receiving port MUST categorize, then count the frames into one
   of two groups:

      1.) Received frames MUST have the correct destination MAC address
          and SHOULD match a signature field.

      2.) Flood count [2].

   Any frame originating from the DUT/SUT MUST not be counted as a
   received frame.  Frames originating from the DUT/SUT MAY be counted
   as flooded frames or not counted at all.






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   Frame loss rate of the DUT/SUT SHOULD be reported as defined in
   section 26.3 [3] with the following notes: Frame loss rate SHOULD be
   measured at the end of the trial duration.  The term "rate", for this
   measurement only, does not imply the units in the fashion of "per
   second."

5.3.4.1 Throughput

   Throughput measurement is defined in section 26.1 [3].  A search
   algorithm is employed to find the maximum Oload [2] with a zero Frame
   loss rate [1].  The algorithm MUST adjust Iload to find the
   throughput.

5.3.4.2 Forwarding rate

   Forwarding rate (FR) of the DUT/SUT SHOULD be reported as the number
   of test frames per second that the device is observed to successfully
   forward to the correct destination interface in response to a
   specified Oload.  The Oload MUST also be cited.

   Forwarding rate at maximum offered load (FRMOL) MUST be reported as
   the number of test frames per second that a device can successfully
   transmit to the correct destination interface in response to the MOL
   as defined in section 3.6 [2]. The MOL MUST also be cited.

   Maximum forwarding rate (MFR) MUST be reported as the highest
   forwarding rate of a DUT/SUT taken from an iterative set of
   forwarding rate measurements.  The iterative set of forwarding rate
   measurements are made by adjusting Iload.  The Oload applied to the
   device MUST also be cited.

5.3.5 Reporting format

   The results for these tests SHOULD be reported in the form of a
   graph.  The x coordinate SHOULD be the frame size, the y coordinate
   SHOULD be the test results.  There SHOULD be at least two lines on
   the graph, one plotting the theoretical and one plotting the test
   results.

   To measure the DUT/SUT's ability to switch traffic while performing
   many different address lookups, the number of addresses per port MAY
   be increased in a series of tests.









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RFC 2889          LAN Switch Benchmarking Methodology        August 2000


5.4 Partially meshed unidirectional traffic