rfc1362.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

PAD Option:

   This option will normally be the last entry in the packet.  Its sole
   purpose is to fill the IPX packet to be 576 bytes.  The pad option
   data will contain a repeating sequence of zero's through 0xFF's. This
   should stop compression modems from collapsing the packet and
   destroying the link delay calculation.

   Currently Assigned WOption Numbers (Timer Request Packet):
       Routing Type Option = 0x00;     Option Length = 0001
           Current option data values:
               0       Novell RIP/SAP routing with network
                       number assigned to the link.

       PAD Type Option     = 0xFF;     Option Length = Variable

       Compression Option  = 0x80;     Option Length = Variable
                         (length dependent on compression type)
           Current option data values:
               Byte 1  Compression type
                   0 = Telebit compression (length=3) [6]
                   Telebit Byte 2 - Compression options
                   Telebit Byte 3 - Number compression slots



Allen                                                           [Page 7]

RFC 1362                         IPXWAN                   September 1992


4.2. Timer Response Packet

   +---------------------------------------------------------------+
   | Checksum         | FF FF             | Always FFFF            |
   | Packet Length    | 02 40             | Max IPX size (576 bytes|
   |                  |                   | Hi Lo order)           |
   | Trans Control    | 00                | Hops traversed         |
   | Packet Type      | 04                | Packet Exchange Packet |
   | Dest Net #       | 00 00 00 00       | Local Network          |
   | Dest Node #      | FF FF FF FF FF FF | Broadcast              |
   | Dest Socket #    | 90 04             | Reserved WAN socket    |
   | Source Net #     | 00 00 00 00       | Local Network          |
   | Source Node #    | 00 00 00 00 00 00 | Set to zero            |
   | Source Socket #  | 90 04             | Reserved WAN socket    |
   |------------------+-------------------+------------------------|
   | WIdentifier      | 57 41 53 4D       | Confidence identifier  |
   | WPacket Type     | 01                | Timer Response         |
   | WNode ID         | xx xx xx xx       | Primary Net # of       |
   |                  |                   | sending router         |
   |                  |                   | (Hi Lo order)          |
   | WSequence #      | xx                | Same as Timer Request  |
   |                  |                   | received               |
   | WNum Options     | 02                | 2 Options follow       |
   | WOption Number   | 00                | Define Routing Type    |
   | WAccept Option   | 01                | 0=No,1=Yes,3=Not Applic|
   | WOption Data Len | 00 01             | Option length (Hi Lo)  |
   | WOption Data     | 00                | IPX RIP/SAP Routing    |
   |                  |                   | (Minimum interoperating|
   |                  |                   | requirement). Others   |
   |                  |                   | may be defined by at a |
   |                  |                   | later date by Novell   |
   | WOption Number   | FF                | Pad option             |
   | WAccept Option   | 01                | 0=No,1=Yes,3=Not Applic|
   | WOption Data Len | 02 0E             | Pad data length (Hi Lo)|
   | WOption Data     | 00->FF's          | Repeated sequence of 00|
   |                  |                   | through FF's to stop   |
   |                  |                   | compression modems     |
   |                  |                   | doing any compression  |
   |                  |                   | for link delay calc.   |
   +---------------------------------------------------------------+

   The responses contained within this packet are as described in
   section 4.1. Any unknown options or not supported options from the
   Timer Request should have the WAccept Option set to NO.

   If the Timer Request packet contained more than one Router Type
   option and the "Slave" supports all the options, the "Slave" should
   set the WAccept Option to NO on all Router Types except the Routing



Allen                                                           [Page 8]

RFC 1362                         IPXWAN                   September 1992


   Type which is to be adopted. The "Master" of the link will then adopt
   the routing option specified with the YES setting and complete
   further information exchanges according to that routing standard.

   This packet should contain the same sequence number as the received
   Timer Request. This packet should ONLY be sent by the router
   determining themselves to be the "Slave" of the link.

   Currently Assigned WOption Numbers (Timer Response Packet):
       Routing Type Option = 0x00;     Option Length = 0001
           Current option data values:
              0       Novell RIP/SAP routing with network
                      number assigned to the link.

       PAD Type Option     = 0xFF;     Option Length = Variable

       Compression Option  = 0x80;     Option Length = Variable
                         (length dependant on compression type)
           Current option data values:
               Byte 1  Compression type
                   0 = Telebit compression (length=3) [6]
                   Telebit Byte 2 - Compression options
                   Telebit Byte 3 - Number compression slots




























Allen                                                           [Page 9]

RFC 1362                         IPXWAN                   September 1992


4.3. RIP/SAP Information Request Packet (Router Type=0 Only)

   +---------------------------------------------------------------+
   | Checksum         | FF FF             | Always FFFF            |
   | Packet Length    | 00 63             | Size of header+data    |
   |                  |                   | (Hi Lo order)          |
   | Trans Control    | 00                | Hops traversed         |
   | Packet Type      | 04                | Packet Exchange Packet |
   | Dest Net #       | 00 00 00 00       | Local Network          |
   | Dest Node #      | FF FF FF FF FF FF | Broadcast              |
   | Dest Socket #    | 90 04             | Reserved WAN socket    |
   | Source Net #     | 00 00 00 00       | Local Network          |
   | Source Node #    | 00 00 00 00 00 00 | Set to zero            |
   | Source Socket #  | 90 04             | Reserved WAN socket    |
   |------------------+-------------------+------------------------|
   | WIdentifier      | 57 41 53 4D       | Confidence identifier  |
   | WPacket Type     | 02                | Information Request    |
   | WNode ID         | xx xx xx xx       | Primary Net # of       |
   |                  |                   | sending router         |
   |                  |                   | (Hi Lo order)          |
   | WSequence #      | 00                | Sequence start at 0    |
   | WNum Options     | 01                | 1 Option to follow     |
   | WOption Number   | 01                | Define IPX RIP/SAP     |
   |                  |                   | info exchange          |
   | WAccept Option   | 01                | 0=No,1=Yes,3=Not Applic|
   | WOption Data Len | 00 36             | Option length (Hi Lo)  |
   | WOption Data     |                   |                        |
   |  Link Delay      | xx xx             | Hi Lo link delay in    |
   |                  |                   | milli seconds (see     |
   |                  |                   | below for calculation) |
   |  Common Net #    | xx xx xx xx       | Hi Lo Common Network # |
   |  Router Name     | xx (x 48 decimal) | Router name - as defned|
   |                  |                   | in section 2.          |
   +---------------------------------------------------------------+

















Allen                                                          [Page 10]

RFC 1362                         IPXWAN                   September 1992


Calculation of link delay is performed as follows:

   // Start_time is a time stamp when Timer Request sent out
   // End_time is a time stamp when a Timer Response is
   // received.
   link_delay = end_time - start_time; // 1/18th second
   // We are on a slow net, so add some biasing to help stop
   // multiple workstation sessions timing out on the link
   if (link_delay < 1)
   {
       link_delay = 1;
   }/*IF*/
   link_delay *= 6;   // Add the biasing
   link_delay *= 55;  // Convert link delay to milliseconds

   The "Link Delay" is used as the network transport time when
   advertized in the IPX RIP packet tuple for the network entry "Common
   Net #". For a consistent network, a common link delay is required at
   both ends of the link and is calculated by the link "Master".

   The Common Net # is supplied by the link "Master". This number must
   be unique in the connected internetwork. Each WAN call requires a
   separate number.

   Currently only a single option is defined for the "Information
   Request" packet for Routing Type=0.

























Allen                                                          [Page 11]

RFC 1362                         IPXWAN                   September 1992


4.4. RIP/SAP Information Response Packet (Router Type=0 Only)

   +---------------------------------------------------------------+
   | Checksum         | FF FF             | Always FFFF            |
   | Packet Length    | 00 63             | Size of header+data    |
   |                  |                   | (Hi Lo Order)          |
   | Trans Control    | 00                | Hops traversed         |
   | Packet Type      | 04                | Packet Exchange Packet |
   | Dest Net #       | 00 00 00 00       | Local Network          |
   | Dest Node #      | FF FF FF FF FF FF | Broadcast              |
   | Dest Socket #    | 90 04             | Reserved WAN socket    |
   | Source Net #     | 00 00 00 00       | Local Network          |
   | Source Node #    | 00 00 00 00 00 00 | Set to zero            |
   | Source Socket #  | 90 04             | Reserved WAN socket    |
   |------------------+-------------------+------------------------|
   | WIdentifier      | 57 41 53 4D       | Confidence identifier  |
   | WPacket Type     | 03                | Information Response   |
   | WNode ID         | xx xx xx xx       | Primary Net # of       |
   |                  |                   | sending router         |
   |                  |                   | (Hi Lo order)          |
   | WSequence #      | 00                | Sequence start at 0    |
   | WNum Options     | 01                | 1 Option to follow     |
   | WOption Number   | 01                | Define IPX RIP/SAP     |
   |                  |                   | info exchange          |
   | WAccept Option   | 01                | 0=No,1=Yes,3=Not Applic|
   | WOption Data Len | 00 36             | Option length (Hi Lo)  |
   | WOption Data     |                   |                        |
   |  Link Delay      | xx xx             | Hi Lo link delay (as   |
   |                  |                   | received in Info Requ) |
   |  Common Net #    | xx xx xx xx       | Hi Lo Common Network # |
   |                  |                   | (as received in Info   |
   |                  |                   | request)               |
   |  Router Name     | xx (x 48 decimal) | Router name - as defned|
   |                  |                   | in section 2.          |
   +---------------------------------------------------------------+

   The responses contained within this packet are as described in
   section 4.3.

5. References

   [1] Simpson, W., "The Point-to-Point Protocol (PPP) for the
       Transmission of Multi-protocol Datagrams over Point-to-Point
       Links", RFC 1331, May 1992.

   [2] Malis, A., Robinson, D., and R. Ullman, "Multiprotocol
       Interconnect on X.25 and ISDN in the Packet Mode", RFC 1356,
       August 1992.



Allen                                                          [Page 12]

RFC 1362                         IPXWAN                   September 1992


   [3] Bradley, T., Brown, C., and A. Malis, "Multiprotocol Interconnect
       over Frame Relay", RFC 1294, January 1992.

   [4] Simpson, W., "The PPP Internetwork Packet Exchange Control
       Protocol (IPXCP) Compromise Version", Work in Progress.

   [5] Novell IPX Router Specification. Novell Part Number 107-000029-
       001. (Note:  Currently, this document is only available as part
       of a Novell developers program as part of an SDK. Novell Labs,
       Provo (UT) should be able to provide more information on this
       document.)

   [6] Lewis, M., Telebit Corp. "IPX Header Compression based on Van
       Jacobson Header Compression for TCP/IP", Work in Progress,
       contact: ([e-mail]).

6. Security Considerations

       Security issues are not discussed in this memo.

7. Author's Address

       Michael Allen
       Novell, Inc.
       2180 Fortune Drive
       San Jose, CA 95131

       EMail: [e-mail]

       Chair's Address:

       The working group can be contacted via the current chair:

       Brian Lloyd
       Lloyd & Associates
       3420 Sudbury Road
       Cameron Park, California 95682

       EMail: [e-mail]

       Phone: [phone]










Allen                                                          [Page 13]