Network Working Group                                      R. Mandeville
Internet-Draft                             European Network Laboratories
Expiration Date: November 1999 May 2000                                      J. Perser
                                                          Netcom Systems
                                                                May
                                                           November 1999

           Benchmarking Methodology for LAN Switching Devices
                    <draft-ietf-bmwg-mswitch-01.txt>
                    <draft-ietf-bmwg-mswitch-02.txt>

Status of this Memo

  This document is an Internet-Draft and is in full conformance with
  all provisions of Section 10 of RFC2026.

  Internet-Drafts are working documents of the Internet Engineering
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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
2. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
3. Test setup . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
4. Frame formats and sizes  . . . . . . . . . . . . . . . . . . . . .  3
5. Benchmarking Tests . . . . . . . . . . . . . . . . . . . . . . . .  4
   5.1  Fully meshed throughput, frame loss and forwarding rates  . .  4
   5.2  Partially meshed overloading  . . . one-to-many/many-to-one  . . . . . . . . . .  7
   5.3  Partially meshed multiple devices . . .  7
   5.3  Head of line blocking . . . . . . . . . . . 10
   5.4  Partially meshed unidirectional traffic . . . . . . . . . 10
   5.4  Partially meshed multiple devices . . 13
   5.5  Congestion Control  . . . . . . . . . . . . 13
   5.5  Multiple streams of unidirectional traffic . . . . . . . . . 15 16
   5.6  Filter illegal frames  Forward Pressure and Maximum Forwarding Rate  . . . . . . . . 19
   5.7  Address caching capacity  . . . . . . . . . . . . 18
   5.7  Broadcast frame handling and latency . . . . . . 21
   5.8  Address learning rate . . . . . . 20
   5.8  Maximum forwarding rate and minimum interframe gap . . . . . 21
   5.9  Address caching capacity . . . . . . . . . 24
   5.9  Errored frames filtering. . . . . . . . . . 23
5.10 Address learning rate . . . . . . . . . 26
   5.10 Broadcast frame Forwarding and Latency  . . . . . . . . . . . 26 28
6. Security Considerations  . . . . . . . . . . . . . . . . . . . . 28 . 29
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
8. Authors' Address . . . . . . . . . . . . . . . . . . . . . . . 28 . . 30
   Appendix A: Formulas . . . . . . . . . . . . . . . . . . . . . . 29 . 31
   Appendix B: Generating Offered Load  . . . . . . . . . . . . . . . 33

1. Introduction

   This document is intended to provide methodology for the benchmarking
   of local area network (LAN) switching devices.  It extends the
   methodology already defined for benchmarking network interconnecting
   devices in RFC 2544 [3] to switching devices.

   This RFC primarily deals with devices which switch frames at the
   Medium Access Control (MAC) layer. It provides a methodology for
   benchmarking switching devices, forwarding performance, congestion
   control, latency, address handling and filtering. In addition to
   defining the tests, this document also describes specific formats for
   reporting the results of the tests.

   A previous document, "Benchmarking Terminology for LAN Switching
   Devices" (RFC 2285), [2], defined many of the terms that are used in this
   document.  The terminology document SHOULD be consulted before
   attempting to make use of this document.

2. Requirements

   The following RFCs SHOULD be consulted before attempting to make use
   of this document:

   * RFC 1242 "Benchmarking Terminology for Network Interconnect
               Devices"

   * [1], RFC 2285 "Benchmarking Terminology for LAN Switching Devices"

   * [2], and RFC 2544 "Benchmarking Methodology for Network Interconnect
               Devices" [3].

   For the sake of clarity and continuity, this RFC adopts the template
   for benchmarking tests set out in Section 26 of RFC 2544.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in
   this document are to be interpreted as described in RFC 2119.

3. Test setup

   This document extends the general test setup described in section 6
   of RFC 2544 [3] to the benchmarking of LAN switching devices.
   RFC 2544 [3] primarily describes non-meshed traffic where input and
   output interfaces  are grouped in mutually exclusive sending and
   receiving pairs.  In fully meshed traffic, each interface of a
   DUT/SUT is set up to both receive and transmit frames to all the
   other interfaces under test.

   Prior to each test run, the DUT/SUT MUST learn the MAC addresses used
   in the test and the address learning SHOULD be verified.  Addresses
   not learned will be forwarded as flooded frames and reduce the amount
   of correctly forwarded frames.  The rate at which address learning
   frames are offered may have to be adjusted to be as low as 50 frames
   per second or even less, to guarantee successful learning.  The
   DUT/SUT address aging time SHOULD be configured to be greater than
   the period of the learning phase of the test plus the test trial duration
   plus any configuration time required by the testing device.
   Addresses SHOULD NOT age out until the test trial duration is completed.
   More than one learning trial may be needed for the association of the
   address to the port to occur.

   If a DUT/SUT uses a hashing algorithm with address learning, the
   DUT/SUT may not learn the necessary addresses to perform the tests.
   The format of the MAC addresses MUST be adjustable so that the
   address mapping may be re-arranged to make a DUT/SUT learn addresses
   without confusion.

   It is recommended that SNMP and Spanning Tree be disabled when bench-
   marking switching devices unless investigating overhead behavior. If
   such protocols cannot be turned off, it is recommended ensure that the
   levels of offered load be reduced (less than 100%) to allow for DUT/SUT learns
   all the additional management frames. addresses.

4.  Frame formats and sizes

   The test frame format is defined in RFC 2544 section 8 [3] and MUST
   contain a unique signature field located in the UDP DATA area of the
   Test Frame (see Appendix C of RFC 2544). [3]).  The purpose of the signature field
   is filter out frames that are not part of the offered load.

   The signature field MUST be unique enough to identify the frames not
   originating from the DUT/SUT.  The signature field SHOULD be located
   after byte 56 (ISO/IEC 8802-3 collision window) (collision window [4] ) or at the end of the frame.
   The length, contents and method of detection is not defined in this
   memo.

   The signature field MAY have a unique identifier per port.  This
   would filter out misforwarded frames.  It is possible for a DUT/SUT
   to strip off the MAC layer, send it through its switching matrix,
   and transmit it out with the correct destination MAC address but the
   wrong payload.

   For frame sizes, refer to RFC 2544, section 9. 9 [3].

   There are three possible frame formats for layer 2 Ethernet switches:
   standard MAC Ethernet frames, standard MAC Ethernet frames with
   vendor-specific tags added to them, and IEEE 802.3ac frames tagged to
   accommodate 802.3p&q. 802.1p&Q.  The two types of tagged frames may exceed the
   standard maximum length frame of 1518 bytes, and may not be accepted
   by the interface controllers of some DUT/SUTs. It is recommended to
   check the compatibility of the DUT/SUT with tagged frames before
   testing.

   Devices switching tagged frames of over 1518 bytes will have a lower
   different maximum forwarding rate than standard untagged frames.

5. Benchmarking Tests

   The following tests offer objectives, procedures, and reporting
   formats for benchmarking LAN switching devices.

5.1  Fully meshed throughput, frame loss and forwarding rates

5.1.1 Objective

   To determine the throughput, frame loss and forwarding rates of
   DUT/SUTs offered fully meshed traffic as defined in RFC 2285. 2285 [2].

5.1.2 Setup Parameters

   When offering bursty full 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. 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).

      Interburst Gap (IBG) - This is the interval between bursts Ethernet) of
      traffic.  Refer to Appendix A Formulas, for the formula used to
      compute IBG. medium being tested.

      Duplex mode - Half duplex or full duplex.

      Load / Port

      ILoad - Intended Load per port is expressed in a percentage of the
      medium's maximum intended load possible.  The actual transmitted
      frame per second is dependent upon half duplex theoretical load, regardless of traffic
      orientation or full duplex
      operation.  The mode.  Certain test SHOULD be run multiple times with a different
      load per port in each case.

      In half duplex mode, exactly half of the intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, configurations will
      theoretically over-subscribe the intended load for each port under
      test is 7440 frames received per second and 7440 frames
      transmitted per second (for 10Mbps Ethernet). DUT/SUT.

      In full duplex mode, the entire intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, half duplex, an ILoad over 50% will over-subscribe the intended load for each port under
      test is 14880 frames received per second and 14880 frames
      transmitted per second (for 10Mbps Ethernet). DUT/SUT.

      Burst Size - The burst size defines the number of frames sent
      back-to-back at the minimum legal IFG (96 bit times) [4] before pausing
      transmission to receive frames.  Burst sizes SHOULD vary between 1
      and 930 frames.  A burst size of 1 will simulate non-bursty traffic. 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 values are 1, 16 and 256.

      Test value is 1.

      Trial Duration - Test The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.
      RFC 2285 recommends a duration of at least 10 seconds for each
      test.

5.1.3 Procedure

   All ports on the tester MUST transmit the exact number of frames. test frames either in a Frame
   Based or Time Based mode (Appendix B).  All ports SHOULD start
   transmitting their frames within 1% of the test trial duration.  For a test
   trial duration of 10 30 seconds, all ports SHOULD have started
   transmitting frames with 100 within 300 milliseconds of each other.

   Each port in the test MUST send test frames to all other ports in a
   round robin type fashion.  The sequence of addresses MUST NOT change
   when backpressure is applied.  The following table shows how each
   port in a test MUST transmit test frames to all other ports in the
   test.  In this example, there are six ports with 1 address per port:

   Source Port       Destination Ports (in order of transmission)

   Port #1           2       3       4       5       6       2...
   Port #2           3       4       5       6       1       3...
   Port #3           4       5       6       1       2       4...
   Port #4           5       6       1       2       3       5...
   Port #5           6       1       2       3       4       6...
   Port #6           1       2       3       4       5       1...

   As shown in the table, there is an equal distribution of destination
   addresses for each transmit opportunity. This keeps the test balanced
   so that one destination port is not overloaded by the test algorithm
   and all ports are equally and fully loaded throughout the test.  Not
   following this algorithm exactly will produce inconsistent results.

   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 MUST be sent to
   allow the DUT/SUT to
   allow the DUT/SUT update its address tables properly.

5.1.4 Measurements

   Each port should receive the same number of test frames that it
   transmitted.  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: defined in RFC 2285 3.8.3.

   Any frame received which does not have the correct destination
   address MUST not be counted as a received frame and SHOULD be counted
   as part of a flood count. count [2].

   Any frame originating from the DUT/SUT (spanning tree, SNMP, RIP,
   ...) 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.

   Frame loss rate of the DUT/SUT SHOULD be reported as defined in
   RFC 2544
   section 26.3 [3] with the following notes: Frame loss rate SHOULD be
   measured at the end of the test trail duration.  The term "rate", for this
   measurement only, does not imply the units in the fashion of "per seconds."
   second."

5.1.4.1 Throughput

   Throughput measurement is defined in RFC 2544.

   Forwarding rate (FR) of the 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.

5.1.4.2 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
   transmit
   forward to the correct destination interface in response to a
   specified offered load. Oload.  The offered load 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
   maximum offered load MOL as defined in RFC 2285, section 3.6. 3.6 [2]. The
   maximum offered load 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 load iterative set of forwarding rate
   measurements are made by adjusting Iload.  The Oload applied to the
   device MUST also be cited.

5.1.5 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.

5.2  Partially meshed overloading 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. 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).

      Interburst Gap (IBG) - This is the interval between bursts Ethernet) of
      traffic.  Refer to Appendix A, Calculating Interburst Gap, for the formula used to compute IBG. medium being tested.

      Duplex mode - Half duplex or full duplex.

      Load / Port

      ILoad - Intended Load per port is expressed in a percentage of the
      medium's maximum intended load possible.  The actual transmitted
      frame per second is dependent upon half duplex theoretical load, regardless of traffic
      orientation or full duplex
      operation.  The mode.  Certain test SHOULD be run multiple times with a different
      load per port in each case.

      In half duplex mode, exactly half of the intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, configurations will
      theoretically over-subscribe the intended load for each port under
      test is 7440 frames received per second and 7440 frames
      transmitted per second (for 10Mbps Ethernet). DUT/SUT.

      In full half duplex mode, the entire intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, bidirectional traffic, an ILoad over 50% will over-
      subscribe the intended load for each port under
      test is 14880 frames received per second and 14880 frames
      transmitted per second (for 10Mbps Ethernet). DUT/SUT.

      Burst Size - The burst size defines the number of frames sent
      back-to-back at the minimum legal IFG (96 bit times) [4] before pausing
      transmission to receive frames.  Burst sizes SHOULD vary between 1
      and 930 frames.  A burst size of 1 will simulate non-bursty traffic. 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 values are 1, 16 and 256.

      Test value is 1.

      Trial Duration - Test The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.
      RFC 2285 recommends a duration of at least 10 seconds for each
      test.

5.2.3 Procedure

   In this test, each transmitting port

   All ports on the tester MUST transmit the exact number
   of frames. 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.

   Frames  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.  Frames  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.

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: defined in RFC 2285 3.8.3.

   Any frame received which does not have the correct destination
   address MUST not be counted as a received frame and SHOULD be counted
   as part of a flood count. 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 offered load. Oload.  The offered load 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
   maximum offered load MOL as defined in RFC 2285, section 3.6. 3.6 [2]. The
   maximum offered load 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 load 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.

5.3 Head-of-line blocking Partially meshed multiple devices

5.3.1 Objective

   To determine how a DUT handles congestion.  Namely, does the device
   implement congestion control throughput, frame loss and forwarding rates of two
   switching devices equipped with multiple ports and does congestion on one port
   affect an uncongested port? high speed
   backbone uplink (Gigabit Ethernet, ATM, SONET).

5.3.2 Setup Parameters

   The

   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. 9 [3].  The four CRC
      bytes are included in the frame size specified.

      Duplex mode -  Half duplex or full duplex.

      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). 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 values are 1, 16 and 256.

      Test value is 1.

      Trial Duration - Test The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.
      RFC 2285 recommends a duration of at least 10 seconds for each
      test.

5.3.3 Procedure

   This test MUST consist of a multiple

        Local Traffic - A Boolean value of four ports.  Four ports are
   REQUIRED and ON or OFF.  The frame
sequence
      algorithm MAY be expanded altered to fully utilize remove local traffic.  With local
      traffic ON, the DUT/SUT in
   increments of four.  Each group of four will contain a test block
   with two of algorithm is exactly the ports same as source transmitters and two of a fully meshed
      throughput.  With local traffic OFF, the port sends frames to all
      other ports as
   receivers. The diagram below depicts on the flow other side of traffic between the
   switch ports:

        +----------+   50 % MOL                  +-------------+
        |          |  ------------------------>  |             |
        |          |   50 % MOL                  | uncongested |
        |          |  ---------                  |             |
        +----------+            \                +-------------+
                                 \
                                  \
                                   \
        +----------+                \            +-------------+
        |          |                 --------->  |             |
        |          |   100 % MOL                 | congested   |
        |          |  ------------------------>  |             |
        +----------+                             +-------------+

   Both source transmitters MUST transmit backbone uplink in a round
      robin type fashion.

5.3.3 Procedure

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

   Each port in the two receive test MUST send test frames to all other ports in an alternating order.  The first
   frame 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 uncongested receive entire
   load across the backbone uplink.

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

   For every address, the testing device MUST
   transmit send learning frames at to
   allow the MOL only 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 congested receive port.

   Both receive ports SHOULD distinguish between frames originating from into one
   of two groups:

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

      2.) Flood count [2].

   Any frame originating from the DUT/SUT.  Only
   frames DUT/SUT MUST not be counted as a
   received frame.  Frames originating from the source ports SHOULD be counted.

   The uncongested receive port should DUT/SUT MAY be receiving counted
   as flooded frames or not counted at a all.

   Frame loss rate of half
   the MOL.  The number of frames received on the uncongested port DUT/SUT SHOULD be 50% of the frames transmitted by reported as defined in
   section 26.3 [3] with the first source
   transmitter.  The congested receive port should following notes: Frame loss rate SHOULD be receiving
   measured at the
   MOL.  The number end of frames received on the congested port should be
   between 100% and 150% of the frames transmitted by one source
   transmitter.

   Frames destined to uncongested ports in a switch device should not
   be dropped due to other ports being congested, even if the source
   is sending to both the congested and uncongested ports.

5.3.4 Measurements

   Any frame received which does not have the correct destination
   address MUST not be counted as a received frame and SHOULD be counted
   as part of a flood count.

   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.

   Frame loss rate of the DUT/SUT's congested and uncongested ports MUST
   be reported as defined in RFC 2544 section 26.3 with the following
   notes:  Frame loss rate SHOULD be measured at the end of the test trial duration.  The term "rate", for this
   measurement only, does not imply the units in the fashion of "per seconds."
   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's congested and uncongested ports
   MUST DUT/SUT SHOULD be reported as the number
   of test frames per second that the device is observed to successfully transmit
   forward to the correct destination interface in response to a
   specified offered load. Oload.  The offered load Oload MUST also be cited.

5.3.5 Reporting format

   This test MUST report the frame lost

   Forwarding rate at the uncongested port,
   the maximum forwarding rate (at 50% offered load) at the uncongested
   port, and the frame lost rate at load (FRMOL) MUST be reported
   as the congested port.  This number of test MAY
   report the frame counts transmitted and frame counts received by the
   ports.

   If the DUT implements frames per second that a flow control mechanism, an indication of this
   is presented by observing no frame loss on the congested port.  It
   should be noted that this test expects the overall load device can
   successfully transmit to the
   congested port correct destination interface in
   response to be greater than 100%. Therefore if the load is
   greater than 100% and no frame loss is detected, then the DUT must be
   implementing a flow control mechanism. MOL as defined in section 3.6 [2]. The type of flow control
   mechanism used is beyond MOL MUST also
   be cited.

   Maximum forwarding rate (MFR) MUST be reported as the scope highest
   forwarding rate of this memo.

   If there is frame loss at the uncongested port, "Head a DUT/SUT taken from an iterative set of Line"
   blocking exists.
   forwarding rate measurements.  The DUT cannot forward the amount iterative set of traffic forwarding rate
   measurements are made by adjusting Iload.  The Oload applied to the
   congested port and as a result it is
   device MUST also losing frames destined to
   the uncongested port.

   It should be noted that some DUTs may not cited.

5.3.5 Reporting format

   The results for these tests SHOULD be able to handle the 100%
   load presented at reported in the input port. In this case, there may form of a
   graph.  The x coordinate SHOULD be the frame
   loss reported at size, the uncongested port which is due to y coordinate
   SHOULD be the load test results.  There SHOULD be at least two lines on
   the
   input port rather than graph, one plotting the congested port's load.

   If theoretical and one plotting the uncongested frame loss is reported as zero, but test
   results.

   To measure the maximum
   forwarding rate is less than 7440 (for 10Mbps Ethernet), then this
   may be an indication of congestion control being enforced by the DUT.
   In this case, the congestion control is affecting DUT/SUT's ability to switch traffic while performing
   many different address lookups, the throughput number of
   the uncongested port.

   If no congestion control is detected, the expected percentage frame
   loss for the congested addresses per port is 33% at 150% overload.  It is receiving
   100% load from 1 port, and 50% from another, and can only get 100%
   possible throughput, therefore having
   MAY be increased in a frame loss rate series of 33%
   (150%-50%/150%). tests.

5.4 Partially Meshed Multiple Devices meshed unidirectional traffic

5.4.1 Objective

   To determine the throughput, frame loss and forwarding rates throughput of two
   switching devices equipped with the DUT/SUT when presented multiple Ethernet
   streams of unidirectional traffic with half of the ports and one high
   speed backbone uplink (Gigabit Ethernet, ATM, SONET). on the
   DUT/SUT are transmitting frames destined to the other half of the
   ports.

5.4.2 Setup Parameters

   When offering bursty partially meshed traffic, the

   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. 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).

      Interburst Gap (IBG) - This is the interval between bursts Ethernet) of
      traffic.  Refer to Appendix A, Calculating Interburst Gap, for the formula used to compute IBG. medium being tested.

      Duplex mode - Half duplex or full duplex.

      Load / Port

      ILoad - Intended Load per port is expressed in a percentage of the
      medium's maximum intended load possible.  The actual transmitted
      frame per second is dependent upon half duplex theoretical load, regardless of traffic
      orientation or full duplex
      operation.  The mode.  Certain test SHOULD be run multiple times with a different
      load per port in each case.

      In half duplex mode, exactly half of configurations will
      theoretically over-subscribe the intended load SHOULD be
      transmitted to each of DUT/SUT.

      ILoad will not over-subscribe the ports under DUT/SUT in this test. For example, with a
      100% load of 64-byte frames,

      Burst Size - The burst size defines the intended load for each port under
      test is 7440 frames received per second and 7440 frames
      transmitted per second (for 10Mbps Ethernet).

      In full duplex mode, the entire intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, the intended load for each port under
      test is 14880 frames received per second and 14880 frames
      transmitted per second (for 10Mbps Ethernet).

      Burst Size - The burst size defines the number of number of frames sent
      back-to-back at the minimum legal IFG (96 bit times) [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 values are 1, 16 and 256.

      Test value is 1.

      Trial Duration - Test The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.
      RFC 2285 recommends

5.4.3 Procedure

   Ports do not send and receive test frames simultaneously.  As a duration of at least 10 seconds for each
      test.

        Local Traffic - A Boolean value of ON or OFF.  The frame
sequence
      algorithm MAY
   consequence, there should be altered to remove local traffic.  With local
      traffic ON, no collisions unless the algorithm DUT is exactly the same as a fully meshed
      throughput.  With local traffic OFF, the port sends
   misforwarding frames, generating flooded or Spanning-Tree frames to all
      other or
   is enabling some flow control mechanism.  Ports used for this test
   are either transmitting or receiving, but not both. Those ports on the other side which
   are transmitting send test frames destined to addresses corresponding
   to each of the backbone uplink in ports receiving.  This creates a round
      robin type fashion.

5.4.3 Procedure unidirectional mesh
   of traffic.

   All ports on the tester MUST transmit the exact number of frames. test frames either in a Frame
   Based or Time Based mode (Appendix B).  All ports SHOULD start
   transmitting their frames within 1% of the test trial duration.  For a test
   trial duration of 10 30 seconds, all ports SHOULD have started
   transmitting frames with 100 300 milliseconds of each other.

   Each transmitting port in the test MUST send frames to all other receiving
   ports in a round robin type fashion as defined in section 5.1.  Local traffic
   MAY be removed from the round robin list fashion.  The sequence of addresses MUST
   NOT change when backpressure is applied.   The following table shows
   how each port in order a test MUST transmit test frames to send all other ports
   in the entire
   load across test.  In this 8 port example, port 1 through 4 are
   transmitting and ports 5 through 8 are receiving; each with 1 address
   per port:

   Source Port, then Destination Ports (in order of transmission)

   Port #1              5       6       7       8       5       6...
   Port #2              6       7       8       5       6       7...
   Port #3              7       8       5       6       7       8...
   Port #4              8       5       6       7       8       5...

   As shown in the backbone uplink. table, there is an equal distribution of destination
   addresses for each transmit opportunity. This keeps the test balanced
   so that one destination port is not overloaded by the test algorithm
   and all receiving ports are equally and fully loaded throughout the
   test.  Not following this algorithm exactly will product inconsistent
   results.

   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 load its address tables properly.  The address
   table's aging time SHOULD be set sufficiently longer than the
   learning time and trial duration time combined.  If the address table
   ages out during the test, the results will show a lower performing
   DUT/SUT.

   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.

5.4.4 Measurements

   Each port should receive the same amount of frames that is
   transmitted.  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 (defined in RFC 2285 3.8.3).

   Any frame received which does not have the correct destination
   address MUST not be counted as a received frame and SHOULD be counted
   as part of a 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.

   Frame loss rate of the DUT/SUT SHOULD be reported as defined in
   RFC 2544
   section 26.3 [3] with the following notes: Frame loss rate SHOULD be
   measured at the end of the test trial duration.  The term "rate", for this
   measurement only, does not imply the units in the fashion of "per seconds."

   Forwarding rate (FR) of the DUT/SUT SHOULD
   second."

5.4.4.1 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.

5.4.4.2 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
   transmit
   forward to the correct destination interface in response to a
   specified offered load. Oload.  The offered load 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
   maximum offered load MOL as defined in RFC 2285, section 3.6. 3.6 [2]. The
   maximum offered load 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 load iterative set of forwarding rate
   measurements are made by adjusting Iload.  The Oload applied to the
   device MUST also be cited.

5.4.5 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.

5.5 Multiple streams of unidirectional traffic Congestion Control

5.5.1 Objective

   To determine how a DUT handles congestion.  Does the throughput of the DUT/SUT when presented multiple
   streams of unidirectional traffic with half of the ports device implement
   back pressure (congestion control) and does congestion on the
   DUT/SUT are receiving frames destined to the other half one port
   affect an uncongested port.  This procedure determines if Head of the
   ports.

5.1.2
   Line Blocking and/or Backpressure are present.

5.5.2 Setup Parameters

   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. 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.

      Load / Port - Load

      Addresses per port is expressed in a percentage of - Represents the
      medium's maximum intended load possible.  The actual transmitted
      frame per second is dependent upon half duplex or full duplex
      operation.  The test SHOULD be run multiple times with a different
      load per port in number of addresses which
      are being tested for each case.

      In half duplex mode, exactly half port.  Number of the intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, the intended load for each port under
      test is 7440 frames received per second and 7440 frames
      transmitted per second (for 10Mbps Ethernet).

      In full duplex mode, the entire intended load SHOULD be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, the intended load for each port under
      test is 14880 frames received per second and 14880 frames
      transmitted per second (for 10Mbps Ethernet).

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

      Test value is 1.

      Trial Duration - Test The recommended Trial Duration is 30 seconds.
      Trial duration SHOULD be adjustable between 1 and 300 seconds.
      RFC 2285 recommends a duration of at least 10 seconds for each
      test.

5.5.3 Procedure

   Ports do not send and receive frames simultaneously. As a
   consequence, there should be no collisions unless the DUT is
   misforwarding frames, generating flooded or Spanning-Tree frames or
   is enabling some flow control mechanism.  Ports used for this

   This test
   are either transmitting or receiving, but not both. Those ports which
   are transmitting send frames destined to addresses corresponding to
   each MUST consist of the ports receiving. This creates a unidirectional mesh multiple of
   traffic.

   All four ports.  Four ports MUST transmit are
   REQUIRED and MAY be expanded to fully utilize the exact number DUT/SUT in
   increments of frames.  All ports SHOULD
   start transmitting their frames within 1% four.  Each group of the test duration.  For four will contain a test duration block
   with two of 10 seconds, all the ports SHOULD have started
   transmitting frames with 100 milliseconds as source transmitters and two of each other.

   Each transmitting port in the test MUST send frames to all receiving ports in a round robin type fashion. as
   receivers. The following table shows how
   each port in a diagram below depicts the flow of traffic between the
   switch ports:

        +----------+   50 % MOL                  +-------------+
        |          |  ------------------------>  |             |
        |          |   50 % MOL                  | uncongested |
        |          |  ---------                  |             |
        +----------+            \                +-------------+
                                 \
                                  \
                                   \
        +----------+                \            +-------------+
        |          |                 --------->  |             |
        |          |   100 % MOL                 | congested   |
        |          |  ------------------------>  |             |
        +----------+                             +-------------+

   Both source transmitters MUST transmit the exact number of test
   frames.  The first source MUST transmit test frames to all other ports in at the
   test.  In this 8 port example, port 1 through 4 are transmitting and
   ports 5 through 8 are receiving; each MOL with 1
   the destination address per port:

   Source Port, then Destination Ports (in order of transmission)

   Port #1              5       6       7       8       5       6...
   Port #2              6       7       8       5       6       7...
   Port #3              7       8       5       6       7       8...
   Port #4              8       5       6       7       8       5...

   As shown in the table, there is two receive ports in an equal distribution of destination
   addresses for each transmit opportunity. This keeps the alternating
   order.  The first test balanced
   so that one destination port is not overloaded by frame to the uncongested receive port, second
   test algorithm
   and all receiving ports are equally and fully loaded throughout frame to the
   test.  Not following this algorithm exactly will product inconsistent
   results.

   For tests using multiple addresses per congested receive port, then repeat.  The second
   source transmitter MUST transmit test frames at the actual port
   destinations are the same as described above and MOL only to the actual
   source/destination address pairs
   congested receive port.

   Both receive ports SHOULD be chosen randomly to
   exercise distinguish between test frames originating
   from the DUT/SUT's ability to perform address lookups.

   For every address, source ports and frames originating from the testing device MUST send learning DUT/SUT.  Only
   test frames to
   allow from the DUT/SUT to load its address tables properly.  The address
   table's aging time source ports SHOULD be set sufficiently longer than the
   learning time and test duration time combined.  If the address table
   ages out during the test, the results will show counted.

   The uncongested receive port should be receiving at a lower performing
   DUT/SUT.

   To measure the DUT/SUT's ability to switch traffic while performing
   many different address lookups, rate of half
   the MOL.  The number of addresses per test frames received on the uncongested port
   MAY
   SHOULD be increased in a series 50% of tests.

5.5.4 Measurements

   Each the test frames transmitted by the first source
   transmitter.  The congested receive port should receive be receiving at the same
   MOL.  The number of test frames that it
   transmitted.  Each receiving received on the congested port MUST categorize, then count should
   be between 100% and 150% of the test frames into transmitted by one of two groups:

      1.) Received Frames: received source
   transmitter.

   Test frames MUST have destined to uncongested ports in a switch device should
   not be dropped due to other ports being congested, even if the correct
          destination MAC address source
   is sending to both the congested and SHOULD match a signature field.

      2.) Flood count: defined in RFC 2285 3.8.3. uncongested ports.

5.5.4 Measurements

   Any frame received which does not have the correct destination
   address MUST not be counted as a received frame and SHOULD be counted
   as part of a flood count.

   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.

   Frame loss rate of the DUT/SUT SHOULD DUT/SUT's congested and uncongested ports MUST
   be reported as defined in
   RFC 2544 section 26.3 [3] with the following notes:
   Frame loss rate SHOULD be measured at the end of the test trial duration.
   The term "rate", for this measurement only, does not imply the units
   in the fashion of "per seconds."

   Forwarding rate (FR) of second."

   Offered Load to the DUT/SUT SHOULD MUST be reported as the number of test
   frames per second that the device is DUT/SUT observed to successfully
   transmit to the correct destination interface in response to a
   specified offered load. The offered load MUST also accept.  This may be cited.
   different that the MOL.

   Forwarding rate at maximum offered load (FRMOL) (FR) of the DUT/SUT's congested and uncongested ports
   MUST be reported as the number of test frames per second that a the
   device can is observed to successfully transmit to the correct
   destination interface in response to the
   maximum a specified offered load as defined in RFC 2285, section 3.6. load. The
   maximum
   offered load MUST also be cited.

   Maximum forwarding rate (MFR)

5.5.5 Reporting format

   This test MUST be reported as report the highest
   forwarding frame lost rate of a DUT/SUT taken from an iterative set of at the uncongested port,
   the maximum forwarding rate measurements. The load applied to the device MUST
   also be cited.

5.1.5 Reporting format

   The results for these tests SHOULD be reported in (at 50% offered load) at the form of a
   graph.  The x coordinate SHOULD be uncongested
   port, and the frame size, the y coordinate
   SHOULD be the test results.  There SHOULD be lost rate at least two lines on the graph, one plotting congested port.  This test MAY
   report the theoretical frame counts transmitted and one plotting the test
   results.

   To measure frame counts received by the DUT/SUT's ability to switch traffic while performing
   many different address lookups,
   DUT/SUT.

5.5.5.1 HOLB

   If there is frame loss at the number of addresses per port
   MAY be increased in a series uncongested port, "Head of tests.

5.6 Filter illegal frames

5.6.1 Objective Line"
   blocking is present.  The objective DUT cannot forward the amount of traffic to
   the filter illegal frame test congested port and as a result it is also losing frames destined
   to determine
   the behavior of the DUT under errors or abnormal uncongested port.

5.5.5.2 Back Pressure

   If there is no frame conditions.
   The results of loss on the congested port, then backpressure
   is present.  It should be noted that this test indicate if the DUT/SUT filters the errors,
   or simply propagates expects the errored frames along overall
   load to the destination.

5.1.2 Setup Parameters

   The following parameters MUST congested port to be defined.  Each variable is
   configured with greater than 100%. Therefore if the following considerations.

      Load / Port - Load per port
   load is expressed in greater than 100% and no frame loss is detected, then the DUT
   must be implementing a percentage flow control mechanism.  The type of flow
   control mechanism used is beyond the
      medium's maximum intended scope of this memo.

   It should be noted that some DUTs may not be able to handle the 100%
   load possible.  The actual transmitted presented at the input port. In this case, there may be frame per second
   loss reported at the uncongested port which is dependent upon half duplex or full duplex
      operation.  The test SHOULD be run multiple times with a different due to the load per port in each case.

      Test Duration - Test duration SHOULD be between 1 and 300 seconds.
      RFC 2285 recommends a duration of at least 10 seconds for each
      test.

5.6.3 Procedure

   Each of the illegal frames for Ethernet MUST be checked:

   Oversize - The DUT/SUT MAY filter frames larger
   input port rather than 1518 bytes
   from being propagated through the DUT/SUT (ISO 8802-3 4.2.4.2.1).
   Oversized frames transmitted to congested port's load.

   If the DUT/SUT should not appear as
   receive frames or uncongested frame loss is reported as error frames on any port.  DUT/SUT supporting
   tagged Frames MAY forward frames up to and including 1522 bytes
   long (IEEE 802.3ac 4.2.4.2.1).

   Undersize - The DUT/SUT MUST filter frames zero, but the maximum
   forwarding rate is less than 64 bytes from 7440 (for 10Mbps Ethernet), then this
   may be an indication of congestion control being propagated through the DUT/SUT (per ISO 8802-3 4.2.4.2.2).
   Undersized frames (or collision fragments) transmitted to enforced by the DUT/SUT
   MUST not appear as receive frames or as error frames on another port.

   CRC Errors - The DUT/SUT MUST filter frames that fail DUT.
   In this case, the Frame Check
   Sequence Validation (ISO 8802-3 4.2.4.1.2) from being propagated
   through congestion control is affecting the DUT/SUT.  Frames with an invalid CRC transmitted to throughput of
   the
   DUT/SUT should not appear as receive frames or as error frames on
   another uncongested port.

   Dribble Bit Errors - The DUT/SUT MUST correct and forward frames
   containing dribbling bits.  Frames transmitted to

   If no congestion control is detected, the DUT/SUT that do
   not end in an octet boundary but contain a valid expected percentage frame check sequence
   MUST be accepted by the DUT/SUT (ISO 8802-3 4.2.4.2.1) and forwarded
   to
   loss for the correct receive congested port with the frame ending in an octet
   boundary (ISO 8802-3 3.4).

   Alignment Errors - The DUT/SUT MUST filter frames than fail the Frame
   Check Sequence Validation AND do not end in an octet boundary.  This is 33% at 150% overload.  It is receiving
   100% load from 1 port, and 50% from another, and can only get 100%
   possible throughput, therefore having a combination frame loss rate of a CRC error 33%
   (150%-50%/150%).

5.6 Forward Pressure and Maximum Forwarding Rate

5.6.1 Objective

   The Forward Pressure test overloads a Dribble Bit error.  When both
   errors are occurring in the same frame, the DUT/SUT MUST determine
   the CRC error takes precedence port and filters measures the frame (ISO 8802-3
   4.2.4.1.2) from being propagated.

5.7 Broadcast frame handling and latency test

5.7.1 Objective
   output for forward pressure [2].  If the DUT/SUT transmits frames
   with an interframe gap less than 96 bits (section 4.2.3.2.2 [4]),
   then forward pressure is detected.

   The objective of the Broadcast Frame Handling and Latency Test Maximum Forwarding Rate test is to
   determine measure the throughput and latency
   peak value of the DUT Forwarding Rate when handling
   broadcast traffic.  The ability to forward broadcast frames will
   depend on special features built into the device for that purpose.
   It Offered Load is therefore necessary to determine varied
   between the ability of switches to
   handle broadcast frames, since there may be many different ways of
   implementing such a feature.

5.7.2 throughput [1] and the Maximum Offered Load [2].

5.6.2 Setup Parameters

   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. 9 [3].  The four CRC
      bytes are included in the frame size specified.

      Duplex mode - Half duplex or full duplex.

      Load / Port

      Trial Duration - Load per port is expressed in a percentage of the
      medium's maximum intended load possible. The actual transmitted
      frame per second recommended Trial Duration is dependent upon half duplex or full duplex
      operation.  The test 30 seconds.
      Trial duration SHOULD be run multiple times with a different
      load per port in each case.

      In half duplex mode, exactly half of adjustable between 1 and 300 seconds.

        Step Size - The minimum incremental resolution that the intended load SHOULD Iload
will
      be
      transmitted to each of the ports under test. For example, with a
      100% load of 64-byte frames, the intended load for each port under
      test is 7440 incremented in frames received per second second.  The smaller the step size,
      the more accurate the measurement and 7440 frames
      transmitted per second (for 10Mbps Ethernet).

      In full duplex mode, the entire intended load SHOULD be
      transmitted to each of more iterations
      required.  As the ports under test. For example, with a
      100% load of 64-byte frames, Iload approaches the intended load for each port under
      test is 14880 frames received per second and 14880 frames
      transmitted per second (for 10Mbps Ethernet).

      Test Duration - Test duration SHOULD be between 1 and 300 seconds.
      RFC 2285 recommends a duration MOL, the minimum step size
      will increase because of at least 10 seconds for each
      test.

5.7.3 gap resolution on the testing device.

5.6.3 Procedure

   For this test, there are two parts to be run.

   Broadcast Frame

5.6.3.1 Maximum forwarding rate

   If the Throughput - This portion of [1] and the test uses a single
   source test port to transmit frames with a broadcast address using MOL [2] are the frame specified in RFC 2544.  Selected receive ports same, then
   measure MFR [2]
   is equal to the forwarding rate and Frame loss rate.

   Broadcast Frame Latency - MOL [2].

   This test uses the same setup as the
   Broadcast Frame throughput, but instead of MUST at a large stream of minimum be performed in a two-port configuration
   as described below.  Learning frames
   being sent, only one frame is MUST be sent and the latency to each of allow the
   receive ports
   DUT/SUT to update its address tables properly.

   Test frames are measured in seconds.

5.7.4 Measurements

   Frame loss rate transmitted to the first port (port 1) of the DUT/SUT SHOULD be reported as defined in
   RFC 2544 section 26.3 with the following notes:  Frame loss rate
   SHOULD be measured
   at the end Iload.  The FR [2] on the second port (port 2) of the test duration. DUT/SUT
   is measured.  The term "rate", Iload is incremented for this measurement only, does not imply the units in each Step Size to find the fashion of
   "per seconds."

   Forwarding rate (FR) of
   MFR.  The algorithm for the DUT/SUT SHOULD be reported test is as the number
   of frames per second that the device is observed to successfully
   transmit to the correct destination interface follows:

    CONSTANT
      MOL = ... frames/sec; {Maximum Offered Load}
    VARIABLE
      MFR   := 0 frames/sec; {Maximum Forwarding Rate}
      ILOAD := starting throughput in response to a
   specified offered load. The offered load MUST also be cited.

5.8 Maximum forwarding rate and minimum interframe gap

5.8.1 Objective

   The objective of the Maximum forwarding rate test is frames/sec; {offered load}
      STEP  := ... frames/sec; {Step Size}
    BEGIN
      ILOAD := ILOAD - STEP;
      DO
      BEGIN
        ILOAD := ILOAD + STEP
        IF (ILOAD > MOL) THEN
        BEGIN
          ILOAD := MOL
        END
        AddressLearning; {Port 2 broadcasts with its source address}
        Transmit(ILOAD); {Port 1 sends frames to find the
   peak value of the Port 2 at Offered load}
        IF (Port 2 Forwarding Rate when the Offered Load is varied
   between the throughput (RFC 1242) and > MFR) THEN
        BEGIN
           MFR := Port 2 Forwarding Rate; {A higher value than before}
        END
    END
    WHILE (ILOAD < MOL); {ILOAD has reached the Maximum Offered Load
   (RFC 2285). MOL value}
    DONE

5.6.3.2 Minimum Interframe Gap

   The Minimum Interframe gap Test overloads test SHOULD, at a minimum, be performed in
   a two-port configuration as described below.  Learning frames MUST be
   sent to allow the DUT/SUT port and measure to update its address tables properly.

   Test frames SHOULD be transmitted to the output for forward pressure.  If first port (port 1) of the
   DUT/SUT transmits frames with an interframe gap less than 96 bits (ISO 8802-3 4.2.3.2.2), then of 88 bits.  This will apply forward
   pressure is detected.

5.8.2 Setup Parameters to the DUT/SUT and overload it at a rate of one byte per
   frame.  The following parameters test frames MUST be defined.  Each variable is
   configured constructed with the following considerations.

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

      Duplex mode - Half duplex or full duplex.

      Test Duration - Test duration SHOULD be between a source address of
   port 1 and 300 seconds.
      RFC 2285 recommends a duration destination address of at least 10 seconds for each
      test.

        Step Size - The minimum incremental resolution that the Offered
      Load (OL) will be incremented in frames per second. port 2.

   The smaller
      the step size, the more accurate the measurement and FR on the more
      iterations required.  As second port (port 2) of the Offered Load approaches DUT/SUT is measured.  The
   measured Forwarding Rate should not exceed the Maximum
      Offered Load, medium's maximum
   theoretical utilization (MOL).

5.6.4 Measurements

   Port 2 MUST categorize, then count the minimum step size will increase because frames into one of gap
      resolution on the testing device.

5.8.3 Procedure

   If two groups:

      1.) Received Frames: received frames MUST have the throughput correct
          destination MAC address and the Maximum Offered Load are the same, then
   Maximum Forwarding rate is equal to the Maximum Offered Load.

   This test SHOULD at match a minimum signature field.

      2.) Flood count [2].

   Any frame originating from the DUT/SUT MUST not be performed in counted as a two-port
   configuration
   received frame.  Frames originating from the DUT/SUT MAY be counted
   as described below.  Learning flooded frames or not counted at all.

5.6.5 Reporting format

   MFR MUST be sent to
   allow reported as the highest forwarding rate of a DUT/SUT to update its address tables properly.
   taken from an iterative set of forwarding rate measurements. The first port (port 1)
   Iload applied to the device transmits frames at MUST also be cited.

   Forwarding rate (FR) of the Offered Load
   to DUT/SUT SHOULD be reported as the DUT/SUT.  A second port (port 2) receives number
   of frames from the
   DUT/SUT and measures per second that the Forwarding Rate.

   The Offered Load device is incremented for each Step Size observed to successfully
   transmit to find the
   Maximum Forwarding Rate.  The algorithm for the test is as follows:

    CONSTANT
      MOL = ... frames/sec; {Maximum Offered Load}
    VARIABLE
      MFR   := 0 frames/sec; {Maximum Forwarding Rate}
      OLOAD := starting throughput correct destination interface in frames/sec; {offered load}
      STEP  := ... frames/sec; {Step Size}
    BEGIN
      OLOAD := OLOAD - STEP;
    DO
    BEGIN
      OLOAD := OLOAD + STEP
      IF (OLOAD > MOL) THEN
      BEGIN
        OLOAD := MOL
      END
        AddressLearning; {Port 2 broadcast frame with its source
address}
      Transmit(OLOAD); {Port 1 sends frames response to Port 2 at Offered load}
      IF (Port 2 Forwarding Rate > MFR) THEN
      BEGIN
         MFR := Port 2 Forwarding Rate; {A higher value than before}
      END
    END
    WHILE (OLOAD >= MOL); {MFR equals Maximum Forwarding Rate}
    DONE a
   specified Oload. The Iload MUST be cited and the Oload MAY be
   recorded.

   If the FR exceeds the MOL during the Minimum Interframe gap test SHOULD, at a minimum, test,
   this MUST be performed in highlighted with the expression "Forward Pressure
   detected".

5.7 Address Caching Capacity

5.7.1 Objective

   To determine the address caching capacity of a two-port configuration LAN switching device
   as described below.  Learning frames defined in RFC 2285, section 3.8.1 [2].

5.7.2 Setup Parameters

   The following parameters MUST be
   sent to allow defined.  Each variable is
   configured with the following considerations.

     Age Time - The maximum time that a DUT/SUT to update its will keep a learned
     address tables properly. in its forwarding table.

     Addresses Learning Rate - The first port (port 1) device transmits frames with an interframe
   gap of 88 bits to the DUT/SUT.  This will apply forward pressure rate at which new addresses are
     offered to the DUT/SUT and overload it at a to be learned.  The rate of one byte at which address
     learning frames are offered may have to be adjusted to be as low as
     50 frames per frame. second or even less, to guarantee successful
     learning.

     Initial Addresses - The
   frames initial number of addresses to start the
     test with.  The number MUST be constructed with a source address of port between 1 and a
   destination address of port 2.

   A second port (port 2) receives frames from the DUT/SUT and measures maximum number
     supported by the Forwarding Rate. implementation.

5.7.3 Procedure

   The measured Forwarding Rate SHOULD not exceed aging time of the medium's maximum theoretical utilization.

5.8.4 Measurements

   Port 2 DUT/SUT MUST categorize, then count be known.  The aging time MUST be
   longer than the time necessary to produce frames into one of two groups:

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

      2.) Flood count: defined in RFC 2285 3.8.3.

   Any low frame received which does not have rate is used for the correct destination
   address MUST not test, then it may be counted as
   possible that sending a received frame and SHOULD be counted
   as part large amount of a flood count.

   Any frame originating from frames may actually take
   longer than the DUT/SUT aging time.

   This test MUST not at a minimum be counted as performed in a
   received frame.  Frames originating from the DUT/SUT three-port
   configuration described below.  The test MAY be counted
   as flooded frames or not counted at all.

5.8.5 Reporting format

   Maximum forwarding rate (MFR) MUST be reported as expanded to fully
   utilized the highest
   forwarding rate of a DUT/SUT taken from in increments of two or three ports.  An
   increment of two would include an iterative set additional Learning port and Test
   port.  An increment of
   forwarding rate measurements. three would include an additional Learning
   port, Test port, and Monitoring port.

   The load applied Learning port (Lport) transmits learning frames to the device MUST
   also be cited.

   Forwarding rate (FR) of the DUT/SUT SHOULD be reported as
   with varying source addresses and a fixed destination address
   corresponding to the number address of frames per second that the device is observed to successfully
   transmit to the correct destination interface in response connected to a
   specified offered load. The offered load MUST also be cited.

5.9 Address Caching Capacity

5.9.1 Objective

   To determine the address caching capacity Test port
   (Tport) of a LAN switching device
   as defined in RFC 2285, section 3.8.1.

5.9.2 Setup Parameters

   The following parameters MUST be defined.  Each variable is
   configured the DUT/SUT.  By receiving frames with varying
   source addresses, the following considerations.

     Age Time - The maximum time that a DUT/SUT will keep a learned
     address in its forwarding table.

     Addresses Learning Rate - The rate at which should learn these new addresses.  The
   source addresses are
     offered to the DUT/SUT to MAY be learned. in sequential order.

   The rate at which address Test port (Tport) of the DUT/SUT acts as the receiving port for
   the learning frames.  Test frames are offered may have to be adjusted to will be as low as
     50 frames per second or even less, to guarantee successful
     learning.

     Initial Addresses - The initial number of addresses to start the
     test with.  The number MUST be between 1 and the maximum number
     supported by the implementation.

5.9.3 Procedure

   The aging time of the DUT/SUT MUST be known.  The aging time MUST be
   longer than the time necessary to produce frames at the specified
   rate.  If a low frame rate is used for the test, then it may be
   possible that sending a large amount of frames may actually take
   longer than the aging time.

   This test SHOULD at a minimum be performed in a three-port
   configuration as described below.

   This test MUST consist of a multiple of three ports.  Three ports
   are REQUIRED and MAY be expanded to fully utilized the DUT/SUT in
   increments of three.  Each group of three will contain a test
   block as follows:

   The first port (port 1) send frames with varying source addresses and
   a fixed destination address corresponding to the MAC address of the
   receiving port (port 2) of the DUT/SUT. By receiving frames with
   varying source addresses, the DUT/SUT will learn these new addresses
   from the sending port of the test device.  The source addresses MAY
   be in sequential order.

   A second port (port 2) acts as the receiving port for the address
   learning frames.  This port also sends test frames back transmitted back to the
   addresses learned on the first Learning port.  The algorithm for this is
   explained below.

   A third

   The Monitoring port (port 3) (Mport) on the DUT/SUT act acts as a monitoring port
   to listen for flooded or mis-forwarded frames.  If the test spans
   multiple broadcast domains (VLANs), each broadcast domain REQUIRES a
   Monitoring port.

   It is highly recommended that SNMP, Spanning Tree, and any other
   frames originating from the DUT/SUT be disabled when running this
   test.  If such protocols cannot be turned off, the flood count MUST
   be modified only to count test frame originating from port 1 Lport and MUST
   NOT count frames originating from the DUT/SUT.

   The algorithm for the test is as follows:

   CONSTANT
      AGE = ...;  {value greater that DUT aging time}
      MAX = ...;  {maximum address support by implementation}
    VARIABLE
      LOW  := 0;    {Highest passed valve}
      HIGH := MAX;  {Lowest failed value}
      N    := ...;  {user specified initial starting point}
    BEGIN
      DO
        BEGIN
        PAUSE(AGE);   {Age out any learned addresses}
          AddressLearning(Port 2);
          AddressLearning(TPort); {broadcast a frame with its source
                                  Address and broadcast destination}
          AddressLearning(Port 1);
          AddressLearning(LPort); {N frames with varying source
addresses
                                  to Port 2}
        Transmit(Port 2); Test Port}
        Transmit(TPort); {N frames with varying destination addresses
                           corresponding to Port 1} Learning Port}
        IF (Port 3 (MPort receive frame != 0) OR
           (Port 1
           (LPort receive frames < Port 2 TPort transmit) THEN
          BEGIN  {Address Table of DUT/SUT was full}
            HIGH := N;
          END
        ELSE
          BEGIN  {Address Table of DUT/SUT was NOT full}
            LOW := N;
          END
        N := LOW + (HIGH - LOW)/2;
      END WHILE (HIGH - LOW < 2);
    END {Value of N equals number of addresses supported by DUT/SUT}

   Using a binary search approach, the test targets the exact number of
   addresses supported per port with consistent test iterations.  Due
   to the aging time of DUT/SUT address tables, each iteration may take
   some time during the waiting period for the addresses to clear.  If
   possible, configure the DUT/SUT for a low value for the aging time.

   Once the high and low values of N meet, then the threshold of address
   handling has been found.

5.9.4

5.7.4 Measurements

   Whether the offered addresses per port was successful forwarded
   without flooding.

5.9.5

5.7.5 Reporting format

   After the test is run, results for each iteration SHOULD be displayed
   in a table to include:

      The number of addresses used for each test iteration (varied).

      The intended load used for each test iteration (fixed).

      Number of test frames that were transmitted by test port number 2. offered to Tport of the DUT/SUT.
      This SHOULD match the number of addresses used for the test
      iteration.  Test frames are the frames sent with varying
      destination addresses to confirm that the DUT/SUT has learned
      all of the addresses for each test iteration.

      The flood count on port 2 Tport during the test portion of each test.
      If the number is non-zero, this is an indication of the DUT/SUT
      flooding a frame in which the destination address is not in the
      address table.

      The number of frames correctly forwarded to test port 1 Lport during
      the test portion of the test.  Received frames MUST have the
      correct destination MAC address and SHOULD match a signature
      field.  For a passing test iteration, this number should be equal
      to the number of frames transmitted by port 2. Tport.

      The flood count on port 1 Lport during the test portion of each test.
      If the number is non-zero, this is an indication of the DUT/SUT
      flooding a frame in which the destination address is not in the
      address table.

      The flood count on port 3. Mport.  If the value is not zero, then this
      indicates that for that test iteration, the DUT/SUT could not
      determine the proper destination port for that many frames.  In
      other words, the DUT/SUT flooded the frame to all ports since its
      address table was full.

5.10

5.8 Address Learning Rate

5.10.1

5.8.1 Objective

   To determine the rate of address learning of a LAN switching device
   as defined in RFC 2285, section 3.8.2.

5.10.2 device.

5.8.2 Setup Parameters

   The following parameters MUST be defined.  Each variable is
   configured with the following considerations.

     Age Time - The maximum time that a DUT/SUT will keep a learned
     address in its forwarding table.

     Initial Addresses Learning Rate - The starting rate at which new
     addresses are offered to the DUT/SUT to be learned.

     Number of Addresses - The number of addresses that the DUT/SUT must
     learn.  The number MUST be between 1 and the maximum number
     supported by the implementation.  It is recommended no to exceed
     the address caching capacity found in section 5.9

5.10.3

5.8.3 Procedure

   The aging time of the DUT/SUT MUST be known.  The aging time MUST be
   longer than the time necessary to produce frames at the specified
   rate.  If a low frame rate is used for the test, then it may be
   possible that sending a large amount of frames may actually take
   longer than the aging time.

   This test SHOULD MUST at a minimum be performed in a three-port
   configuration as described below.

   This in section 5.9.3.  The test MUST consist of a multiple of three ports.  Three ports
   are REQUIRED and MAY be expanded to fully
   utilized the DUT/SUT in increments of three.  Each group two or three ports.  An
   increment of two would include an additional Learning port and Test
   port.  An increment of three will contain a test
   block as described in section 5.9. would include an additional Learning
   port, Test port, and Monitoring port.

   An algorithm similar to the one used to determine address caching
   capacity can be used to determine the address learning rate.  This
   test iterates the rate at which address learning frames are offered
   by the test device connected to the DUT/SUT.  It is recommended to
   set the number of addresses offered to the DUT/SUT in this test to
   the maximum caching capacity.

   The address learning rate might be determined for different numbers
   of addresses but in each test run, the number MUST remain constant
   and SHOULD be equal to or less than the maximum address caching
   capacity.

5.10.4

5.8.4 Measurements

   Whether the offered addresses per port was were successful forwarded
   without flooding at the offered learning rate.

5.10.5

5.8.5 Reporting format

   After the test is run, results for each iteration SHOULD be displayed
   in a table:

      The number of addresses used for each test iteration (fixed).

      The intended load used for each test iteration (varied).

      Number of test frames that were transmitted by test port number 2. Tport.  This SHOULD
      match the number of addresses used for the test iteration.  Test
      frames are the frames sent with varying destination addresses to
      confirm that the DUT/SUT has learned all of the addresses for each
      test iteration.

      The flood count on port 2 Tport during the test portion of each test.
      If the number is non-zero, this is an indication of the DUT/SUT
      flooding a frame in which the destination address is not in the
      address table.

      The number of frames correctly forwarded to test port 1 Lport during
      the test portion of the test.  Received frames MUST have the
      correct destination MAC address and SHOULD match a signature
      field.  For a passing test iteration, this number should be equal
      to the number of frames transmitted by port 2. Tport.

      The flood count on port 1 Lport during the test portion of each test.
      If the number is non-zero, this is an indication of the DUT/SUT
      flooding a frame in which the destination address is not in the
      address table.

      The flood count on port 3. Mport.  If the value is not zero, then this
      indicates that for that test iteration, the DUT/SUT could not
      determine the proper destination port for that many frames.  In
      other words, the DUT/SUT flooded the frame to all ports since its
      address table was full.

6. Security Considerations

   This document does not yet address Security Considerations.

7. Authors' Address

   Robert Mandeville
   European Network Laboratories (ENL)
   2, rue Helene Boucher
   87286 Guyancourt Cedex
   France

   Phone: + 33 1 39 44 12 05
   EMail: bob@enl.net

   Jerry Perser
   Netcom Systems
   20550 Nordhoff St.
   Chatsworth, CA 91311
   USA

   Phone: + 1 818 700 5100
   Email: jerry_perser@netcomsystems.com

Appendix A:  Formulas

A.1 Calculating

5.9 Errored frames filtering

5.9.1 Objective

   The objective of the InterBurst Gap

   IBG Errored frames filtering test is defined in RFC 2285 as to determine
   the interval between two bursts.  To
   achieve a desired load, behavior of the follow Input Parameter need DUT under error or abnormal frame conditions.
   The results of the test indicate if the DUT/SUT filters the errors,
   or simply propagates the errored frames along to the destination.

5.9.2 Setup Parameters

   The following parameters MUST be
   defined:

     LENGTH defined.  Each variable is
   configured with the following considerations.

      ILoad - Frame size Intended Load per port is expressed in bytes including a percentage of the CRC.

     LOAD   -
      medium's maximum theorical load possible.  The intended actual transmitted
      frame per second is dependent upon half duplex or full duplex
      operation.  The test SHOULD be run multiple times with a different
      load per port in percent.  Range is 0 to 100.

     BURST each case.

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

5.9.3 Procedure

   Each of frames in the burst (integer value).

     SPEED  - media's speed in bits/sec
                 Ethernet is 10,000,000 bits/sec
                 Fast Ethernet is 100,000,000 bits/sec
                 Gigabit illegal frames for Ethernet is 1,000,000,000 bits/sec

     DUPLEX MUST be checked:

   Oversize - A constant The DUT/SUT MAY filter frames larger than 1518 bytes
   from being propagated through the DUT/SUT section 4.2.4.2.1 [4].
   Oversized frames transmitted to adjust the transmit rate for full or half
              duplex mode.  In full duplex DUT/SUT should not be forwarded.
   DUT/SUT supporting tagged Frames MAY forward frames up to and
   including 1522 bytes long (section 4.2.4.2.1 [5]).

   Undersize - The DUT/SUT MUST filter frames less than 64 bytes from
   being propagated through the value is 100, in half
              duplex DUT/SUT (section 4.2.4.2.2 [4]).
   Undersized frames (or collision fragments) received by the value is 200.

     IFG DUT/SUT
   must not be forwarded.

   CRC Errors - A constant 96 bits for the minimum interframe gap. The IBG (in seconds) can DUT/SUT MUST filter frames that fail the Frame Check
   Sequence Validation (section 4.2.4.1.2 [4]) from being propagated
   through the DUT/SUT.  Frames with an invalid CRC transmitted to the
   DUT/SUT should not be calculated:

          (DUPLEX/LOAD forwarded.

   Dribble Bit Errors - 1) * BURST * (IFG + 64 + 8*LENGTH)] + IFG
   IBG = ----------------------------------------------------------
                                  SPEED

A.2 Calculating The DUT/SUT MUST correct and forward frames
   containing dribbling bits.  Frames transmitted to the Number DUT/SUT that do
   not end in an octet boundary but contain a valid frame check sequence
   MUST be accepted by the DUT/SUT (section 4.2.4.2.1 [4]) and forwarded
   to the correct receive port with the frame ending in an octet
   boundary (section 3.4 [4]).

   Alignment Errors - The DUT/SUT MUST filter frames that fail the Frame
   Check Sequence Validation AND do not end in an octet boundary.  This
   is a combination of a CRC error and a Dribble Bit error.  When both
   errors are occurring in the same frame, the DUT/SUT MUST determine
   the CRC error takes precedence and filters the frame (section
   4.2.4.1.2 [4]) from being propagated.

5.9.5 Reporting format

   For each of the error conditions in section 5.6.3, a "pass" or "fail"
   MUST be reported.  Actual frame counts MAY be reported for diagnostic
   purposes.

5.10 Broadcast frame Forwarding and Latency

5.10.1 Objective

   The objective of the Broadcast Frame Forwarding and Latency Test is
   to determine the throughput and latency of the DUT when forwarding
   broadcast traffic.  The ability to forward broadcast frames will
   depend upon a specific function built into the device for that
   purpose.  It is therefore necessary to determine the ability of
   DUT/SUT to handle broadcast frames, since there may be many different
   ways of implementing such a function.

5.10.2 Setup Parameters

   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.

      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.

      ILoad will not over-subscribe the DUT/SUT in this test.

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

5.10.3 Procedure

   For this test, there are two parts to be run.

   Broadcast Frame Throughput - This portion of the test uses a single
   source test port to transmit test frames with a broadcast address
   using the frame specified in RFC 2544 [3].  Selected receive ports
   then measure the forwarding rate and Frame loss rate.

   Broadcast Frame Latency - This test uses the same setup as the
   Broadcast Frame throughput, but instead of a large stream of test
   frames being sent, only one test frame is sent and the latency to
   each of the receive ports are measured in seconds.

5.10.4 Measurements

   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."

   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.

5.10.5 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.

6. Security Considerations

   This document does not yet address Security Considerations.

7.  References

   [1]   Bradner, S., Editor, "Benchmarking Terminology for Network
         Interconnection Devices", RFC 1242, July 1991.

   [2]   Mandeville, R., Editor, "Benchmarking Terminology for LAN
         Switching Devices", RFC 2285, February 1998.

   [3]   Bradner, S., Editor, "Benchmarking Methodology for Network
         Interconnect Devices", RFC 2544, March 1999.

   [4]   ANSI/IEEE, "CSMA/CD Access Method and Physical Layer
         Specifications," ISO/IEC 8802-3, ISBN 0-7381-0330-6, 1998.

   [5]   IEEE Draft, "Frame Extensions for Virtual Bridged Local Area
         Networks (VLAN) Tagging on 802.3 Networks", 802.3ac/D3.1,
         July 1998.

8. Authors' Address

   Robert Mandeville
   European Network Laboratories (ENL)
   2, rue Helene Boucher
   87286 Guyancourt Cedex
   France

   Phone: + 33 1 39 44 12 05
   EMail: bob@enl.net

   Jerry Perser
   Netcom Systems
   20550 Nordhoff St.
   Chatsworth, CA 91311
   USA

   Phone: + 1 818 700 5100
   Email: jerry_perser@netcomsystems.com

Appendix A:  Formulas

A.1 Calculating the InterBurst Gap

   IBG is defined in RFC 2285 [2] as the interval between two bursts.
   To achieve a desired load, the follow Input Parameter need to be
   defined:

     LENGTH - Frame size in bytes including the CRC.

     LOAD   - The intended load in percent.  Range is 0 to 100.

     BURST  - The number of frames in the burst (integer value).

     SPEED  - media's speed in bits/sec
                 Ethernet is 10,000,000 bits/sec
                 Fast Ethernet is 100,000,000 bits/sec
                 Gigabit Ethernet is 1,000,000,000 bits/sec

     IFG    - A constant 96 bits for the minimum interframe gap.

   The IBG (in seconds) can be calculated:

          [(100/LOAD - 1) * BURST * (IFG + 64 + 8*LENGTH)] + IFG
   IBG = -----------------------------------------------------------
                                  SPEED

A.2 Calculating the Number of Bursts for the Trial Duration

   The number of burst for the trial duration is rounded up to the
   nearest integer number.  The follow Input Parameter need to be
   defined:

     LENGTH - Frame size in bytes including the CRC.

     BURST  - The number of frames in the burst (integer value).

     SPEED  - media's speed in bits/sec
                 Ethernet is 10,000,000 bits/sec
                 Fast Ethernet is 100,000,000 bits/sec
                 Gigabit Ethernet is 1,000,000,000 bits/sec

     IFG    - A constant 96 bits for the minimum interframe gap.

     IBG    - Found in the above formula

     DURATION - Trial duration in seconds.

   An intermediate number of the Burst duration needs to be calculated
   first:

                 IFG*(BURST-1) + BURST*(64 + 8*LENGTH)
    TXTIME  =  -----------------------------------------
                               SPEED

   Number of Burst for the Trial Duration (rounded up):

                     DURATION
    #OFBURSTS =   --------------
                  (TXTIME + IBG)

   Example:

     LENGTH   = 64  bytes per frame
     LOAD     = 100 % offered load
     BURST    = 24  frames per burst
     SPEED    = 10  Mbits/sec (Ethernet)
     DURATION = 10  seconds test

       IBG       = 1612.8 uS
         TXTIME    = 1603.2 uS
       #OFBURSTS = 3110

Appendix B: Generating Offered Load

   In testing, the tester is configured with the Iload (Intended Load)
   and measures the Oload (Offered Load).  If the DUT/SUT applies
   backpressure, then the Iload and the Oload are not the same value.
   The question arises, how to generate the Oload?  This appendix will
   describe two different methods.

   Oload is in the units of bits per second.  The two methods described
   here will hold one unit constant and let the DUT/SUT vary the other
   unit.  The tester SHOULD specify which method it uses.

B.1 Frame Based Load

   Frame based load holds the number of bits constant.  The Trial
   Duration will vary based upon back pressure.  Advantage is
   implementation is a simple state machine.  Disadvantage is that Oload
   needs to be measured independently.

   All ports on the tester MUST transmit the exact number of test
   frames.  The exact number is found by multiplying the Iload by the
   Trial Duration.  All ports MAY NOT transmit the same number of frames
   if their Iload is not the same.  An example would be the Partially
   meshed overloading test.

   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.

   Oload MUST be measured independent of Iload.  The reported Oload
   SHOULD be the average during the Trial Duration.  If the tester
   continues to transmit after the Trial Duration due to back pressure,
   Oload MAY be averaged over the entire transmit time.  Oload for the
   DUT/SUT MUST be the aggregate of all the Oloads per port.  Oload per
   port MAY be reported for diagnostic purposes.

B.2 Time Based Load

   Time based load holds the Trial Duration constant, while allowing the
   number of octets transmitted to vary.  Advantages are an accurate
   Trial Duration and integrated Oload measurement.  Disadvantage is
   that the starting and stopping of the transmitters MUST be more
   accurate.

   All ports on the tester are configured to transmit the Iload for an
   indefinite amount of time.  Each port MUST count the number of
   octets successfully transmitted.

   All ports MUST 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 Bursts for each other.

   All ports SHOULD stop transmitting frames after the Test Duration specified trial
   duration, within 100 PPM.  The number of burst for first test frame transmit time minus
   the last test duration is rounded up to frame transmit time SHOULD be within 100 PPM of the
nearest
   integer number.  The follow Input Parameter need to
   trial duration.  Each port's stop time MUST be defined:

     LENGTH - Frame size in bytes including reference to its
   start time.  This trial duration error controls the CRC.

     BURST  - The number accuracy of frames in the burst (integer value).

     SPEED  - media's speed
   Oload measurement and SHOULD be reported with the Oload measurement
   in bits/sec
                 Ethernet the units of PPM.

   Each port is 10,000,000 bits/sec
                 Fast Ethernet allowed an offset error of 1000 PPM and a trial duration
   error of 100 PPM.  At what layer the start and stop is 100,000,000 bits/sec
                 Gigabit Ethernet initiated is 1,000,000,000 bits/sec

     IFG    - A constant 96 bits for
   not defined yet.  The layer MUST complete its transmit process when
   the minimum interframe gap.

     IBG    - Found in stop time is reached (i.e. no fragments, finish the frame).

   Oload is found by taking the above formula
    DURATION - Test duration in seconds.

   An intermediate number of octets successfully
   transmitted and dividing by the Burst duration needs to trial duration.  Oload for the
   DUT/SUT MUST be calculated
   first:

                 IFG*(BURST-1) + BURST*(64 + 8*LENGTH)
    TXTIME  =  -----------------------------------------
                               SPEED

   Number the aggregate of Burst for all the Test Duration (rounded up):

                     DURATION
    #OFBURSTS =   --------------
                  (TXTIME + IBG)

   Example:

     LENGTH   = 64  bytes Oloads per frame
     LOAD     = 100 % offered load
     BURST    = 24  frames port.  Oload per burst
     SPEED    = 10  Mbits/sec (Ethernet)
     DUPLEX   = 200 (half duplex)
     DURATION = 10  seconds test

       IBG       = 1612.8 uS
         TXTIME    = 1603.2 uS
       #OFBURSTS = 3110
   port MAY be reported for diagnostic purposes.