rfc1944.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

         on one port and 198.19.1.1 on the other port.

         Some of the tests described in the methodology memo make use of
         an SNMP management connection to the DUT.  The management
         access address for the DUT is assumed to be the first of the
         "input" ports (198.18.1.1).

      C.2.2.2 Frame addresses
         Some of the described tests assume adjacent network routing
         (the reboot time test for example).  The IP address used in the
         test frame is that of node 2 on the appropriate Class C
         network. (198.19.1.2 for example)

         If the test involves non-adjacent network routing the phantom
         routers are located at node 10 of each of the appropriate Class
         C networks.  A series of Class C network addresses from
         198.18.65.0 to 198.18.254.0 has been assigned for use as the
         networks accessible through the phantom routers on the "input"
         side of DUT.  The series of Class C networks from 198.19.65.0
         to 198.19.254.0 have been assigned to be used as the networks
         visible through the phantom routers on the "output" side of the
         DUT.

   C.2.3 Routing Update Frequency

      The update interval for each routing protocol is may have to be
      determined by the specifications of the individual protocol.  For
      IP RIP, Cisco IGRP and for OSPF a routing update frame or frames
      should precede each stream of test frames by 5 seconds.  This
      frequency is sufficient for trial durations of up to 60 seconds.
      Routing updates must be mixed with the stream of test frames if
      longer trial periods are selected.  The frequency of updates
      should be taken from the following table.




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       IP-RIP  30 sec
       IGRP  90 sec
       OSPF  90 sec

   C.2.4 Frame Formats - detailed discussion

      C.2.4.1 Learning Frame
         In most protocols a procedure is used to determine the mapping
         between the protocol node address and the MAC address.  The
         Address Resolution Protocol (ARP) is used to perform this
         function in TCP/IP.  No such procedure is required in XNS or
         IPX because the MAC address is used as the protocol node
         address.

         In the ideal case the tester would be able to respond to ARP
         requests from the DUT.  In cases where this is not possible an
         ARP request should be sent to the router's "output" port.  This
         request should be seen as coming from the immediate destination
         of the test frame stream. (i.e. the phantom router (Figure 2)
         or the end node if adjacent network routing is being used.) It
         is assumed that the router will cache the MAC address of the
         requesting device.  The ARP request should be sent 5 seconds
         before the test frame stream starts in each trial.  Trial
         lengths of longer than 50 seconds may require that the router
         be configured for an extended ARP timeout.

                      +--------+            +------------+
                      |        |            |  phantom   |------ P LAN
         A
            IN A------|   DUT  |------------|            |------ P LAN
         B
                      |        |   OUT A    |  router    |------ P LAN
         C
                      +--------+            +------------+

                                 Figure 2

           In the case where full routing is being used

      C.2.4.2 Routing Update Frame
         If the test does not involve adjacent net routing the tester
         must supply proper routing information using a routing update.
         A single routing update is used before each trial on each
         "destination" port (see section C.24).  This update includes
         the network addresses that are reachable through a phantom
         router on the network attached to the port.  For a full mesh
         test, one destination network address is present in the routing
         update for each of the "input" ports.  The test stream on each



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         "input" port consists of a repeating sequence of frames, one to
         each of the "output" ports.

      C.2.4.3 Management Query Frame
         The management overhead test uses SNMP to query a set of
         variables that should be present in all DUTs that support SNMP.
         The variables for a single interface only are read by an NMS
         at the appropriate intervals.  The list of variables to
         retrieve follow:

          sysUpTime
          ifInOctets
          ifOutOctets
          ifInUcastPkts
          ifOutUcastPkts

      C.2.4.4 Test Frames
         The test frame is an UDP Echo Request with enough data to fill
         out the required frame size.  The data should not be all bits
         off or all bits on since these patters can cause a "bit
         stuffing" process to be used to maintain clock synchronization
         on WAN links.  This process will result in a longer frame than
         was intended.

      C.2.4.5 Frame Formats - TCP/IP on Ethernet
         Each of the frames below are described for the 1st pair of DUT
         ports, i.e. "input" port #1 and "output" port #1.  Addresses
         must be changed if the frame is to be used for other ports.

      C.2.6.1 Learning Frame

          ARP Request on Ethernet

          -- DATAGRAM HEADER
          offset data (hex)            description
          00     FF FF FF FF FF FF     dest MAC address send to
         broadcast address
          06     xx xx xx xx xx xx     set to source MAC address
          12     08 06                 ARP type
          14     00 01                 hardware type Ethernet = 1
          16     08 00                 protocol type IP = 800
          18     06                    hardware address length 48 bits
         on Ethernet
          19     04                    protocol address length 4 octets
         for IP
          20     00 01                 opcode request = 1
          22     xx xx xx xx xx xx     source MAC address
          28     xx xx xx xx           source IP address



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          32     FF FF FF FF FF FF     requesting DUT's MAC address
          38     xx xx xx xx           DUT's IP address

      C.2.6.2 Routing Update Frame

          -- DATAGRAM HEADER
          offset data (hex)            description
          00     FF FF FF FF FF FF     dest MAC address is broadcast
          06     xx xx xx xx xx xx     source hardware address
          12     08 00                 type

          -- IP HEADER
          14     45                    IP version - 4, header length (4
         byte units) - 5
          15     00                    service field
          16     00 EE                 total length
          18     00 00                 ID
          20     40 00                 flags (3 bits) 4 (do not
         fragment),
                                       fragment offset-0
          22     0A                    TTL
          23     11                    protocol - 17 (UDP)
          24     C4 8D                 header checksum
          26     xx xx xx xx           source IP address
          30     xx xx xx              destination IP address
          33     FF                    host part = FF for broadcast

          -- UDP HEADER
          34     02 08                 source port 208 = RIP
          36     02 08                 destination port 208 = RIP
          38     00 DA                 UDP message length
          40     00 00                 UDP checksum

          -- RIP packet
          42     02                  command = response
          43     01                  version = 1
          44     00 00               0

          -- net 1
          46     00 02               family = IP
          48     00 00               0
          50     xx xx xx            net 1 IP address
          53     00                  net not node
          54     00 00 00 00         0
          58     00 00 00 00         0
          62     00 00 00 07         metric 7

          -- net 2



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          66     00 02               family = IP
          68     00 00               0
          70     xx xx xx            net 2 IP address
          73     00                  net not node
          74     00 00 00 00         0
          78     00 00 00 00         0
          82     00 00 00 07         metric 7

          -- net 3
          86     00 02               family = IP
          88     00 00               0
          90     xx xx xx            net 3 IP address
          93     00                  net not node
          94     00 00 00 00         0
          98     00 00 00 00         0
          102    00 00 00 07         metric 7

          -- net 4
          106    00 02               family = IP
          108    00 00               0
          110    xx xx xx            net 4 IP address
          113    00                  net not node
          114    00 00 00 00         0
          118    00 00 00 00         0
          122    00 00 00 07         metric 7

          -- net 5
          126    00 02               family = IP
          128    00 00               0
          130    00                  net 5 IP address
          133    00                  net not node
          134    00 00 00 00         0
          138    00 00 00 00         0
          142    00 00 00 07         metric 7

          -- net 6
          146    00 02               family = IP
          148    00 00               0
          150    xx xx xx            net 6 IP address
          153    00                  net not node
          154    00 00 00 00         0
          158    00 00 00 00         0
          162    00 00 00 07         metric 7

      C.2.4.6 Management Query Frame

         To be defined.




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      C.2.6.4 Test Frames
              UDP echo request on Ethernet

          -- DATAGRAM HEADER
          offset data (hex)            description
          00     xx xx xx xx xx xx     set to dest MAC address
          06     xx xx xx xx xx xx     set to source MAC address
          12     08 00                 type

          -- IP HEADER
          14     45                    IP version - 4 header length 5 4
         byte units
          15     00                    TOS
          16     00 2E                 total length*
          18     00 00                 ID
          20     00 00                 flags (3 bits) - 0 fragment
         offset-0
          22     0A                    TTL
          23     11                    protocol - 17 (UDP)
          24     C4 8D                 header checksum*
          26     xx xx xx xx           set to source IP address**
          30     xx xx xx xx           set to destination IP address**

          -- UDP HEADER
          34     C0 20                 source port
          36     00 07                 destination port 07 = Echo
          38     00 1A                 UDP message length*
          40     00 00                 UDP checksum

          -- UDP DATA
          42     00 01 02 03 04 05 06 07    some data***
          50     08 09 0A 0B 0C 0D 0E 0F

         * - change for different length frames

         ** - change for different logical streams

         *** - fill remainder of frame with incrementing octets,
         repeated if required by frame length












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   Values to be used in Total Length and UDP message length fields:

          frame size   total