The THC Hack/Phreak Archives: PSNINTRO.DOC (842 lines)
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%!!                     Phreakers/Hackers/Anarchists                      !!%
X!!                     -++--++--++--++--++--++--++-                      !!X
%!!                                                                       !!%
X!!           THE COMPLETE INTRODUCTORY GUIDE TO SPRINTNET AND            !!X
%!!                    SIMILAR PACKET SWITCHED NETWORKS                   !!%
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%!! P/H/A - Written By Doctor Dissector On Sunday, April 22, 1990 - P/H/A !!%
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Part I: Disclaimer
------------------
   The sole purpose of this document is to educate. Neither the author nor
the sponsor group (Phreakers/Hackers/Anarchists) will be held responsible
for the reader's actions before, during, and following exposure to this
document as well as the validity or accuracy of the information contained
within this document.


Part II: Introduction
---------------------
   Packet switching networks can be said to be the most useful tool for both
the inexperienced and the experienced hack. When I first learned about
PSNs (SprintNet/Telenet in general), I discovered that there were not any
good "full length" introductions or guides to the use of these systems. In
effect, scrounging around for a small file here and another there was not
very productive in any sense. So, I decided to compile a "complete"
introduction and guide, as I know it, to the "world" of the packet switched
network. Enjoy!
                                               Doctor Dissector - PHA


Part III: Table Of Contents
---------------------------
   Part    Description
   -----   -------------------------------------------------------------
    I      Disclaimer
    II     Introduction
    III    Table Of Contents
    IV     What Is A Packet Switched Network?
    V      Network Protocols
    VI     PAD Security
    VII    Connection To The SprintNet PAD
    VIII   X.121 International Address Format
    IX     Network User Identification
    X      Setting PAD ITI/X.3 Parameters
    XI     Disconnect Code Sequence
    XII    Misc Network Notes
    XIII   Appendix
    XIV    Conclusion And Closing Notes
    XV     Greets, Hellos, Etc....

   Appendix  Description
   --------  -----------------------------------------------------------
      A      Hunt/Confirm Sequence Codes
      B      PAD Command Summary
      C      ITI/X.3 Parameter Summaries
      D      International DNIC/PSN List
      E      Overseas PSNs Which Accept Collect Calls
      F      Network Protocol List
      G      Glossary


Part IV: What Is A Packet Switched Network?
-------------------------------------------
   A packet switched network can be accessed through any local POTS
dialup/port. Systems known as "hosts" on the PSN pay for connection to
the PSN depending on transmission speed and protocol type. PSNs offer
more efficient data transfer and less rates as compared to the typical
circuit switched call. Thus, to anyone who would be interested in
transferring large amounts of data over either the PSN or the circuit
system, the PSN would result in an increase of convenience due to the
reduction of data transmission error and cost.
   Another feature of the PSN is the speed and data translation which
takes place between the PSN's PAD (Packet Assembler/Disassembler) and
the host. For example, one could connect to the PSN's PAD at 1200 bps
and the PAD could connect to the host system at 9600 bps and still
allow the user to receive error free transmission. This "flow control"
is done by the actual increase or decrease of the data packet between
the PAD and the user or the PAD and the host.
   PSNs also have the ability to interconnect through special gateways
which might allow one user who dialed one PSN's PAD and then connected
to another PSN's PAD through a system which was accessible by the first.
Almost every PSN in the world can be accessed through gateways on one
PSN to another PSN, through subsequent gateways until the target PSN
is achived; of course, there are always exceptions, some private or
small data networks may not be reachable through gateways, these systems
can only be reached, usually, through direct dialins.
    Some PSNs allow the caller to execute "collect calls" to host
systems which accept them, although the majority of the hosts on any
given PSN do not accept collect calls. To connect to a host system which
does not accept collect calls, one must possess a network user identifier
(NUI) or access to a private system on the PSN which accepts collect
calls and has the ability to access another PSN with its own identifier.
These will be discussed further into this document.


Part V: Network Protocols
-------------------------
   The PSN utilizes several communications protocols similar to the
communications protocols used by typical asynchronous modems. However,
MOST PSNs utilize synchronous communications and the X type protocols
versus the typical modem's asynchronous V protocols. As a result, the
PAD of any PSN also serves as a synchronous/asynchronous translator
between the synchronous netowrk and the asynchronous modem.
   Most PSNs offer network speeds from snail's pace baud rates of
300 bps (asynchronous) to the lightning of 48,000 bps (synchronous).
The most common data protocol used by PSNs today is the X.25 protocol,
thus if one were able to access a private PAD which offered support for
the X.25 protocol, one could access virtually any network user address
(NUA) from that PAD. SprintNet PADs support the X.25 protocol, so if
one had an NUI of sorts, one also could access any NUA from the SprintNet
PAD. See appendix F for a list of network protocols.


Part VI: PAD Security
---------------------
   SprintNet PADs and most dialin PADs in general have no "immediate"
form of telephone security common within their systems. Plainly, SprintNet
and most PSN dialin PADs cannot trace on the fly, as they do not have
their own equiptment to trace incomming calls. HOWEVER, this does not
mean that they CANNOT trace; SprintNet can, and will, upon probable
cause, cooperate with the telco to trace calls. Notice that tracing
usually is premeditated and one-time abusers have a very slim chance
of being caught. Also note that most PAD activities are logged and if
abuse is suspected, the PSN owners would most likely suspect the abuser
as originating from the local area, since the POTS dialin/port is also
located in the same area.
   Once online, security from "calling" hosts which do not accept collect
calls is enforced by the presence of the NUI. Without an NUI, one would
usually be stuck, only able to call systems accepting collect calls, sans
the use of another system's NUI.
   There is one more aspect of seucurity worth mentioning. Whenever a
packet of data is sent to a host system, a header of data is sent stating
where the originating "call" is being placed by. Thus, if you were
connecting to "312312" from your local POTS dialin/port that owned an
address of "20231H," the system at 312312 would know the call was being
originated from 20231H. Once again, if someone were abusing any system on
the PSN and that system saved a log of the originating addresses accessing
that system, the owners of the abused system could easily determine which
POTS dialin/port number the abuser was using, and then inform the PSN
security of possible abuse in that dialin's local area. Because of this
ability to "trace" the originating address, there is one way to foil this.
One could connect to another PAD, and then, from that PAD connect to
the target system. Thus, the POTS dialin/port address will be sent to
the connected PAD, and the connected PAD would intercept the POTS address
and send the connected PAD's address to the target system instead of
the POTS address. SO, if the target system was abused and the owners
attempted to "trace" the originating address, they would receive the
address of the connected PAD. For example: you dial your local POTS
dialin/port which had an address of "71516G," log into another PAD at
"415100," connect from 415100 to "213213." The system at 213213 if
"traced" would find that you were originating from 415100, not 71516G.
See how it works? Good... Notice that the system 213213 would still
know that you were originating from 71516G, but the folks you were
genuinely abusing wouldn't know that!


Part VII: Connection To The SprintNet PAD
-----------------------------------------
   The following procedure outlines the methods used to connect to
and through the SprintNet PAD.

Step    Procedures                           Network/Operator Response
----    ----------                           -------------------------
 1      Turn on your terminal. Make sure
        it's Online.

 2      Dial your local SprintNet access
        number.

 3      For data sets Bell 103 & 113 type,
        depress the DATA button.

 4      Enter the hunt/confirm sequence      <CR> <CR>
        for your baud/parity type. For
        E,7,1 1200/2400, type <CR> twice.
        For hunt/confirm sequences, see
        appendix A.

 5      SprintNet will identify itself,      TELENET
        its port address, and then send      909 14B
        a TERMINAL= prompt for terminal
        identification. "D1" specifies       TERMINAL=D1<CR>
        dumb terminal.

 6      NUI Input: After SprintNet gives
        the "@" prompt, type "ID ;" and      @ID ;ABCD<CR>
        then your ID code, follwed by a      PASSWORD=123456<CR>
        <CR>. Then enter your password
        followed by another <CR>. If you
        don't have an NUI, you can always
        access systems which allow collect
        calls.

 7      At the "@" prompt, you can enter     @02341123456790<CR>
        the network user address (NUA) of
        the desired host. If, during the
        connection attempt wish to abort
        the attempt, a BREAK signal will
        bring you back to the "@" prompt.

 8      SprintNet will respond with a        (address) CONNECTED
        connection message, or an error
        message.

 9      To disconnect from your computer,    (address) DISCONNECTED
        log off as usual. SprintNet will
        send a disconnect message. To
        disconnect off of a system without
        logging off, typing "<CR>@<CR>" will
        bring you back to the "@" prompt.


Part VIII: X.121 International Address Format
---------------------------------------------
   Most PSNs around the world follow the X.121 format for access to both
domestic and international hosts. SprintNet does not require some parts
of the format for domestic connection, which will be discussed below.

+-----------------------------------------    Zero Handler For SprintNet
|                                             (Formats The X.121 Address)
|
|
|
|       +---------------------------------    Data Network Identifier
|       |                                     Code (DNIC)
|       |
|       |
|       |       +-------------------------    Area Code of Host
|       |       |
|       |       |
|       |       |         +---------------    DTE Address of Host
|       |       |         |
|       |       |         |
|       |       |         |       +--------    Port Address
|       |       |         |       |
|       |       |         |       |

|0|   |DDDD|   |AAA|    |HHHHH|   |PP|

                                  |
                                  +-------    Optional 'Subaddress'
                                              Field for Packet Mode
                                              DTE

   For a complete list of DNICs/PSNs according to country, please see
appendix D.
   On SprintNet, a "0" MUST lead the NUA, although on other PSNs, this
may not be necessary.
   On SprintNet, the DNIC is defaulted to 3110. Any host entered at the
"@" prompt, if domestic to Telenet/USA, will not require the input of
zero handler or the 3110 DNIC. For example:

          Domestic           X.121          SprintNet Int'l
          ----------     --------------     ---------------
          2129966622     31102129966622     031102129966622
          212869         311021200869       0311021200869
          21244          311021200044       0311021200044


Part IX: Network User Identification
------------------------------------
   Network user identifiers (NUIs) offer full SprintNet PAD use for
any distance or amount of time for any host accessible by the PAD in
question. Think of the NUI as a /<-/<00l Kode for calling long
distance. Any systems that you call are logged, and each call is charged.
At the end of the month, the owner of the NUI is billed. So, it is
possible to hack out NUIs and use them, but like k0dez, abuse kills.
   NUIs can be entered into SprintNet in two ways. The first method is to
type "ID ;xxxx" where xxxx can be from 4-? charachters in length, both
alphabetic and numeric. Then, at the password prompt, enter a password.
   The second method for entering an NUI is in conjunction to the NUA
you are accessing. The format is "<NUA>,<ID>,<PW>" where at the "@"
prompt you would type the desired NUA, followed by a comma, then your
ID followed by a comma, and then your password. Your password will not
be echoed.


Part X: Setting PAD ITI/X.3 Parameters
--------------------------------------
   Online PAD parameter modification may be desired for certain
applications, connections, or data transfers. See appendix C for brief
summaries of these parameters. Modification of these parameters can be
done by the following procedure at the "@" prompt:

   X.3 Parameters
   --------------
   To display current parameters: "PAR?<CR>"
       The PAD will respond with: "PAR1:<VALUE>,2:<VALUE>,..."

   To modify parameter(s): "SET? <PARM>:<VALUE>,<PARM>:<VALUE>,..."
       The PAD will respond with: "PAR<PARM>:<VALUE>,..."

   ITI Parameters
   --------------
   To display current parameters: "PAR? 0,<PARM>,<PARM>,..."
       The PAD will respond with: "PAR<PARM>:<VALUE>,<PARM>:<VALUE>,..."

   To modify parameter(s): "SET? 0:33,<PARM>:<VALUE>,<PARM>:<VALUE>,..."
       The PAD will respond with: "PAR0:33,<PARM>:<VALUE>,..."


Part XI: Disconnect Code Sequence
---------------------------------
   When disconnected off of any host on SprintNet, a disconnect coding
sequence with a string of data will be sent to your terminal. The
following is a translation format for the disconnect coding.

<NUA> DISCONNECTED AA BB TT:TT:TT:TT CCC DD

   Where:
           <NUA> is the NUA of the given host system.
              AA is the clearing code.
              BB is the diagnositc code.
     TT:TT:TT:TT is the time spent on the host.
             CCC is the number of frames received.
              DD is the number of frames sent.


Part XII: Misc Network Notes
----------------------------
   Just a few things one might want to know when using PSNs:

   1) When using/abusing a private PAD, try to use it after business
      hours, as the operators will not tend to discover your presence
      as quickly.

   2) When hacking or abusing ANY system on ANY PSN, if anything seems
      different or suspicious, logoff, disconnect, or HANG-UP
      IMMEDIATELY! Much better SAFE than SORRY!

   3) For a complete and updated list of POTS dialin/ports, dial the
      IN-WATS number at 1-800-546-1000 or 1-800-546-2000, type "MAIL,"
      and for user name and password, enter "PHONES." You will be
      diverted to the SprintNet dialing directory & a menu. From then on
      you will have plenty of info about POTS dialins and port numbers.

   4) For international information concerning SprintNet and other PSNs,
      get to a SprintNet "@" prompt and type "MAIL." Then, for the user
      name, enter "INTL/ASSOCIATES." For the password, type "INTL," and
      you will be diverted to the international information menu.

   5) For even more info on SprintNet and PCP, the NUA for the PCP
      support BBS is 311090900631 (909631 domestic).

   6) Some 2400 bps and 2400+ bps PADs have problems recognizing 8,N,1
      connections. Sometimes they only allow E,7,1 transmissions.
      Experimentation or inquiry may yeild results. SprintNet's customer
      information line is at 1-800-336-0437, overseas is 1-703-689-6400.

   7) PCP outdials and other outdial systems are abundant on the PSNs
      throughout the world. If you have any NUAs to these or find any,
      they utilize the typical Hayes AT command set, so they should be
      easy to figure out. MOST of the time, they ONLY allow dialing of
      local (to the oudial's area code) numbers, but some have been known
      to allow interstate and even international calls. Experimentation,
      again, is always necessary.

   8) Domestically, the "AAA" (Area Code) portion of the NUA is usually
      the same as the area code (NPA) of the same calling area. However,
      some area codes are shared on the network and some non-existant
      area codes such as 909, 223, 224 and others contain hosts.

   9) On any PAD, the data transmission rates may be slowed, due to the
      assembley/disassembley time, called packet delay. Depending on which
      system, baud, and transfer protocol used, pad delay can differ from
      almost none to noticable fractions of seconds. PCP oudials are
      notorious for LLOONNGG pad delays....


Part XIII: Appendix
-------------------
Appendix A: Hunt/Confirm Sequence Codes
=======================================
        Bits  Stop  Parity  Modem Baud  Duplex  Sequence
        ----  ----  ------  ----------  ------  --------
         7     1     EVEN    300-1200    FULL   <CR><CR>
         7     1     EVEN    300-1200    HALF   <CR>;<CR>
         7     1     EVEN      2400      FULL     @<CR>
         7     1     EVEN      2400      HALF     @;<CR>
         8     1     NONE    300-1200    FULL   <CR>D<CR>
         8     1     NONE    300-1200    HALF   <CR>H<CR>
         8     1     NONE      2400      FULL     @D<CR>
         8     1     NONE      2400      HALF     @H<CR>

        At BPS speeds 2400+, wait 1/2 a second BEFORE and AFTER the
        "@" sign in the sequence above.

Appendix B: PAD Command Summary
===============================
   The following is a list of commands usable from the "@" prompt on the
SprintNet PSN.

Command      Description
-----------  -------------------------------------------------------------
<NUA>        Connects to the host specified by that NUA.
C <NUA>      Connects to the host specified by that NUA.
STAT         Displays the network port address (NUA of the port).
FULL         Sets duplex to full.
HALF         Sets duplex to half.
DTAPE        Prepares the PSN for bulk file transfers.
CONT         Continues the current connected session/connect attempt.
BYE          Aborts connect attempt/disconnects from current session.
D            Aborts connect attempt/disconnects from current session.
HANGUP       Logs you off from the SprintNet PAD.
TERM <TERM>  Changes the terminal specification to that of <TERM>.
MAIL         Request connection to SprintNet Telemail.
TELEMAIL     Request connection to SprintNet Telemail.
ID ;<ID>     Enter NUI, <ID> is your ID. This is followed by a PASSWORD
             prompt. Password will not be echoed.
TEST CHAR    Test if you are receiving garbled output. If so, adjust
             parity or data bits, and then try again. If errors persist,
             be sure to complain to SprintNet customer service!
TEST ECHO    Test if your input is being garbled by Telenet. Similar
             otherwise as TEST CHAR.

Appendix C: ITI/X.3 Parameter Summaries
=======================================
Para-                               Para-
meter  Description (Default Value)  meter  Description (Default Value)
-----  ---------------------------  -----  ---------------------------
  1    Line feed Insertion (0)       31+   Interrupt Character (0)
  2    Network Message Display (0)   32    Automatic Hang-up (0)
  3    Echo (1)                      33+   Flush Output (0)
  4    Echo Mask (163)               34    Transmit on Timers (1)
  5    Transmit Mask (2)             35    Idle Timer (80)
  6*   Buffer Size (0)               36    Interval Timer (0)
  7*   Command Mask (127)            37    Network Usage Display (0)
  8*   Command Mask (3)              38    Carriage Return PAD (Variable)
  9    Carriage Return PAD (Fixed)   39    Padding Options (1)
 10    Linefeed Padding              40    Insert on Break (0)

 11    Tab Padding                   41    PAD-Terminal Flow Control (0)
 12    Line Width                    42    PAD-Terminal XON Character (17)
 13    Page Length (0)               43    PAD-Terminal XOFF Character (19)
 14    Line Folding (1)              44*   Generate Break (INV)
 15    Page Wait (0)                 45*   APP on Break (0)
 16    Interrupt on Break (0)        46    Input Unlock Option (0)
 17    Break Code (0)                47    Input Unlock Timer (0)
 18    NVT Options (0)               48    Input Unlock Character (0)
 19    Initial Keyboard State (0)    49    Output Lock Option (2)
 20    Half/Full Duplex              50    Output Lock Timer (10)

 21    Real Character Code           51    Output Lock Option (0)
 22    Printer Style                 53*   Break Options (0)
 23    Terminal Type                 54    Terminal-PAD Flow Control (0)
 24    Permanent Terminal (0)        55    Terminal-PAD XON Character (17)
 25    Manual or Auto Connect (0)    56    Terminal-PAD XOFF Character (19)
 26    Rate                          57    Connection Mode (2)
 27    Delete Character (127)        58    Escape to Command Mode (1)
 28    Cancel Character (24)         59*   Flush Output on Break (0)
 29    Display Character (18)        60    Delayed Echo
 30+   Abort Output Character (0)    63    Eight-bit Transparency (1)
                                     64+   Early ACK (0)
                                     65    More-Data Bit Generation (3)
                                     66    Defer Processing of User (0)
                                     67    ESP Packetizing Option (0)
                                     68    Escape Sequence Timer (0)
                                     69    Escape Sequence Maximum Length (0)
                                     70    Escape Sequence Initiator (0)
                                     71    Parameter Reset on Disconnect (0)

 Note: - All Telenet Parameters must follow the National Option Marker
         (Parameter 0, value '21' Hex) in PAD Messages.
       - Parameters marked with "*" should not be used.
       - Parameters marked with "+" should be used with caution.

Appendix D: International DNIC/PSN List
=======================================
   Note: This is not a complete list!

COUNTRY                     NETWORK                             DNIC
-------                     -------                             ----
ALASKA                      ALASCOM                             3135
ANTIGUA                     ANTIGUA                             3443
ARGENTINA                   ARPAC                               7220
ARGENTINA                   ARPAC                               7222
AUSTRIA                     DATEX-P                             2322
AUSTRIA                     RA                                  2329
AUSTRALIA                   AUSPAC                              5052
AUSTRALIA                   MIDAS                               5053
BAHAMAS                     BATELCO                             3640
BAHRAIN                     IDAS                                4263
BARBADOS                    IDAS                                3423
BELGIUM                     DCS                                 2062
BELGIUM                     DCS-TELEX                           2068
BELGIUM                     DCS-PSTN                            2069
BERMUDA                     IPSD                                3503
BRAZIL                      INTERDATA                           7240
BRAZIL                      RENPAC                              7241
BRAZIL                      RENPAC                              7249
BRAZIL                      RENPAC                              7248
CAMEROON                    CAMPAC                              6242
CANADA                      DATAPAC                             3020
CANADA                      GLOBEDAT                            3025
CANADA                      CNCP                                3028
CANADA                      TYMNET CANADA                       3106
CAYMAN ISLANDS              IDAS                                3463
CHILE                       ENTEL                               7302
CHILE                       ENTEL                               3104
CHINA                       PTELCOM                             4600
COLUMBIA                    DAPAQ                               3107
COSTA RICA                  RACSADATOS                          7120
COSTA RICA                  RACSAPAC                            7122
COSTA RICA                  RACSAPAC                            7128
COSTA RICA                  RACSAPAC                            7129
COTE D'IVOIRE               SYTRANPAC                           6122
DENMARK                     DATAPAK                             2382
DEMMARK                     DATAPAK                             2383
DOMINICAN REPUBLIC          UDTS                                3700
EGYPT                       ARENTO                              6020
FINLAND                     FINNPAK                             2442
FRANCE                      TRANSPAC                            2080
FRANCE                      N.T.I.                              2081
FRANCE                      TRANSPAC                            9330
FRANCE                      TRANSPAC                            9331
FRANCE                      TRANSPAC                            9332
FRANCE                      TRANSPAC                            9333
FRANCE                      TRANSPAC                            9334
FRANCE                      TRANSPAC                            9335
FRANCE                      TRANSPAC                            9336
FRANCE                      TRANSPAC                            9337
FRANCE                      TRANSPAC                            9338
FRANCE                      TRANSPAC                            9339
FRENCH ANTILLES             DOMPAC                              3400
FRENCH GUYANA               DOMPAC                              7420
GABON                       GABONPAC                            6282
GERMANY                     DATEX-P                             2624
GREECE                      HELPAK                              2022
GREENLAND                   DATAPAK                             2901
GUAM                        LSDS-RCA                            5350
GUATEMALA                   GUATEL                              7040
HONDURAS                    HONDUTEL                            7080
HONG KONG                   IDAS                                4542
HONG KONG                   DATAPAK                             4545
HUNGARY                     DATEXL                              2160
HUNGARY                     DATEXL                              2161
ICELAND                     ICEPAC                              2740
INDONESIA                   SKDP                                5101
IRELAND                     IPSS (EIRE)                         2721
IRELAND                     EIREPAC                             2724
ISRAEL                      ISRANET                             4251
ITALY                       DARDO                               2222
ITALY                       ITAPAC                              2227
IVORY COAST                 SYTRANPAC                           6122
JAMAICA                     JAMINTEL                            3380
JAPAN                       DDX-P                               4401
JAPAN                       VENUS-P                             4408
JAPAN                       NISNET                              4406
JAPAN                       NI+CI                               4410
KUWAIT                                                          4263
LEBANON                     SODETEL                             4155
LUXEMBOURG                  LUXPAC                              2704
LUXEMBOURG                  PSTN                                2709
MALAYSIA                    MAYPAC                              5021
MAURITIUS                   MAURIDATA                           6170
MEXICO                      TELEPAC                             3340
NETHERLANDS                 DATANET-1                           2040
NETHERLANDS                 DATANET-1                           2041
NETHERLANDS                 DABAS                               2044
NETHERLANDS                 DATANET                             2049
NETHERLANDS/ANTILLES        UDTS ITT                            3620
NETHERLANDS/MARIANAS        PCINET                              5351
NEW CALEDONIA               TOMPAC NC                           5460
NEW ZEALAND                 PACNET                              5301
NORWAY                      DATAPAK                             2422
PANAMA                      INTELPAQ                            7141
PANAMA                      INTELPAQ                            7142
PHILIPPINES                 CAPWIRE                             5151
PHILIPPINES                 PHILCOM RCA                         5152
PHILIPPINES                 GMCR                                5154
PHILIPPINES                 ETPI-2                              5156
POLYNESIA                   TOMPAC                              5470
PORTUGAL                    TELEPAC                             2680
PORTUGAL                    SABD                                2682
PUERTO RICO                 UDTS- PDIA                          3301
PUERTO RICO                 UDTS- I                             3300
QATAR                       DOHPAC                              4271
REUNION ISLAND              DOMPAC                              6470
SAN MARINO                  X-NET                               2922
SAUDI ARABIA                BAHNET                              4263
SINGAPORE                   TELEPAC                             5252
SINGAPORE                   TELEPAC                             5258
SOUTH AFRICA                SAPONET                             6550
SOUTH AFRICA                SAPONET                             6559
SOUTH KOREA                 DACOM-NET                           4501
SOUTH KOREA                 DNS                                 4503
SPAIN                       TIDA                                2141
SPAIN                       IBERPAK                             2145
SWEDEN                      TELEPAK                             2405
SWEDEN                      DATAPAK                             2402
SWITZERLAND                 TELEPAC                             2284
SWITZERLAND                 DATALINK                            2289
TAHITI                      TOMPAC                              5470
TAIWAN                      UDAS                                4877
TAIWAN                      PACNET                              4872
THAILAND                    IDAR                                5200
TORTOLA                                                         3483
TRINIDAD                    TEXTET                              3740
TRINIDAD                    DATANETT                            3745
TUNISIA                     RED25                               6050
TURKEY                      TURPAC                              2862
TURKS BWI                                                       3763
UNITED ARAB EMIRATES        EMDAN                               4241
UNITED ARAB EMIRATES        TELEX                               4243
UNITED ARAB EMIRATES        TEDAS                               4310
UNITED KINGDOM              IPSS                                2341
UNITED KINGDOM              PSS                                 2342
UNITED KINGDOM              MPDS MERCURY                        2350
UNITED KINGDOM              PSS MERCURY                         2352
U.S.S.R.                    IASNET                              2502
UNITED STATES OF AMERICA    TELENET                             3110
UNITED STATES OF AMERICA    TYMNET                              3106
U.S. VIRGIN ISLANDS