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Table of Contents


— Technical Guide to DataPac —

— Brought to you by the —

— NEW Dark Council (1990) —


— If you can stand reading —

— through this entire —

— document, you are a boring —

— person. Go out and get —

— laid! —


Here is the technical "About DataPac" document so efficiently stolen

from the DataPac information service. (Data

Pac address 92100086).

It probably won't teach you much, but it might be nice to have around

if you ever need to do something out of the ordinary.

DATAPAC FAMILY OF SERVICES


DATAPAC 3000


DATAPAC 3000 IS A SYNCHRONOUS, APPLICATION INDEPENDENT SERVICE THAT

ALLOWS DATA TERMINALS (DTE'S) AND DATA COMMUNICATING EQUIPMENT (DCE)

TO EXCHANGE DATA IN A PACKET-MODE OVER A PUBLIC OR PRIVATE PACKET

SWITCHING NETWORK.

THE DTE/DCE INTERFACE CONNECTION, DISCONNECTION AND TRANS

MISSION RULES

ARE DEFINED IN A PACKET SWITCHING PROTOCOL CALLED X.25 RECOMMENDATION

WHICH IS DEVELOPED AND GOVERNED BY THE INTERNATIONAL TELEPHONE AND

TELEGRAPH CONSULTATIVE COMMITTEE (CCITT).

X.25 PROTOCOL IS A BIT ORIENTED FRAMING STRUCTURE BASED ON THE

HIGH LEVEL DATA LINK CONTROL (HDLC). THE CCITT RECOMMENDATIONS

FOR X.25 ARE DIVIDED INTO THREE LEVELS, NAMELY:

THE PHYSICAL INTERFACE (LEVEL 1);

THE FRAME LEVEL LOGICAL INTERFACE (LEVEL 2);

THE PACKET LEVEL LOGICAL INTERFACE (LEVEL 3).

LEVEL 1

SPE

CIFIES THE USE OF FOUR-WIRE, POINT-TO-POINT SYNCHRONOUS

CIRCUIT BETWEEN THE DTE AND THE NETWORK (DCE). THIS CIRCUIT

INCLUDES TWO MODEMS OR DATASETS (ONE CONNECTED TO THE DTE AND

THE OTHER CONNECTED TO THE NETWORK).

TYPICAL CHARACTERISTICS ARE:

- 4-WIRE POINT-TO-POINT OR DIAL VIA A V.22 BIS MODEM;

- FULL DUPLEX ;

- EIA RS232 CONVENTION.

MODEM/DATASET

LEVEL 2 - DEFINES THE FRAME LEVEL LINK PROCEDURES USED TO SYNCHRONIZE

        TRANSMISSION, INITIATE THE "HANDSHAKING" NECESSARY TO
        ESTABLISH

THE 'R-U-THERE'/YES-I-AM SEQUENCE, FLOW CONTROL

        MECHANISM AND PERFORM ERROR CHECKING OF DATA EXCHANGE
        ACROSS THE DTE/DCE INTERFACE (LINK).  THE DTE IS
        USUALLY LOCATED AT THE CUSTOMER PREMISES AND IS CALLED
        HOST WHILE THE DCE IS LOCATED IN THE NETWORK. THE PROCEDURES
        USED TO CONTROL THE LINK ARE DEFINED AS COMMANDS AND RESPONSES.
        CHARACTERISTICS ARE:
  1. HDLC;
  1. LINK ACCESS PROCEDURE -BALANCED

(LAPB)

  1. X.25(80) OR X.25(84).

LEVEL 3 - DEFINES THE PACKET FORMATS AND CONTROL PROCEDURES REQUIRED

        TO ESTABLISH A LOGICAL PATH (CALL REQUEST), EXCHANGE
        INFORMATION (DATA PACKETS) AND FOR REMOVING THE LOGICAL
        PATH (CLEAR REQUEST) BETWEEN THE DTE AND DCE.
        CHARACTERISTICS ARE:
  1. LOGICAL CHANNELS (LCN`S)
  1. PACKET SIZE
  1. WINDOW SIZE
  1. THROUGHPUT CLASS
  1. ETC

HOW IT WORKS


THE CUSTOMER'S TERMINAL (HOST) IS CONNECTED TO A LOCAL MODEM

WHICH IN TURN, IS CONNECTED TO A SECOND MODEM (REMOTE) IN THE

CENTRAL OFFICE VIA BY 4 WIRES WHICH IN TURN, IS CONNECTED

TO A LINE PROCESSING MODULE IN THE DATAPAC NETWORK. THIS

CONFIGURATION IS CALLED THE DTE/DCE LINK AND CAN BE

ASSIGNED SPEEDS OF 1200 BPS THROUGH 19200 BPS.

THIS DTE/DCE LINK IS ASSIGNED A UNIQUE DATAPAC NETWORK ADDRESS

(DNA) AND OTHER LINK PARA

METERS SUCH AS LINE SPEED, MODEM TYPE,

FLOW CONTROL AND SECURITY BY TELECOM CANADA.

WHEN THE ELECTRICAL SIGNALS ARE IN THE CORRECT STATE AS

SPECIFIED IN LEVEL 1, THE DATAPAC LINE PROCESSING MODULE

CONTINUOUSLY TRANSMITS A CCITT COMMAND CALLED SABM (SET

ASYNCHRONOUS BALANCED MODE) TO THE CUSTOMERS'S TERMINAL

(HOST) EVERY THREE SECONDS. IF THE HOST IS READY, IT

RESPONDS TO THE SABM WITH A CCITT RESPONSE UA (UNNUMBERED

ACKNOWLEDGEMENT). WHEN THIS OCCURS, THE LINK IS INITIALIZED

(LEVEL 2 READY), THE HOST AND

DATAPAC MODULE EXCHANGE

RESTARTS OR RESTART/RESTART CONFIRMATION COMMANDS.

WHEN THIS OCCURS, THE DTE/DCE LINK GENERATES A TRANSITION

TO THE NEXT X.25 LEVEL. LEVEL 3.

THE DTE THEN SIGNALS THE ADDRESS IT WISHES TO COMMUNICATE

WITH IN A CCITT DEFINED CALL REQUEST FORMAT (8 DIGITS ), 10

DIGITS IF USING 9TH AND 10TH DIGIT SUBADDRESSING ON A LOGICAL

CHANNEL (LCN)DATAPAC THEN ROUTES THE CALL REQUEST TO THE APPROPRIATE

DESTINATION (NATIONAL OR INTERNATIONAL) AND AWAITS A CCITT

DEFINED CALL ACCEPT PACKET. IF THIS

OCCURS, THE ACCEPT PACKET IS

TRANSMITTED BACK TO THE ORIGINATING HOST AND BOTH HOSTS MAY NOW

EXCHANGE CCITT DEFINED DATA PACKETS. THIS IS CALLED A SWITCHED

VIRTUAL CALL (SVC); PERMANENT VIRTUAL CALLS (PVC'S) ARE ALSO

OFFERED. AT THE END OF THE SESSION, EITHER HOST CAN TERMINATE THE SVC

BY TRANSMITTING A CCITT DEFINED CLEAR REQUEST PACKET. UP TO 255 SVC'S

MAY BE SUPPORTED SIMULTANEOUSLY.

DIAL ACCESS SERVICE IS ALSO OFFERED AT 2400BPS WITH

A MAXIMUM OF EIGHT LCN'S OVER THE PUBLIC TELEPHONE NETWORK

BENE

FITS

DATAPAC 3000 PROVIDES CUSTOMERS WITH A COST EFFECTIVE SERVICE

DERIVED FROM PACKET SWITCHING TECHNOLOGY AND X.25 PROTOCOL.

SOME BENEFITS ARE:

DEDICATED OR DIAL-IN ACCESS

- SIMULTANEOUS COMMUNICATION WITH MANY (UP TO 255) DIFFERENT

 LOCATIONS - NATIONAL AND INTERNATIONAL;

- ERROR FREE TRANSMISSION;

- SYSTEM EXPANSION FLEXIBILITY;

COMMUNICATION UNIVERSALITY

- COST CONTAINMENT THROUGH REDUCED HOST PORT CONNECTIONS;

- 24 HOURS 7 DAYS-A-WEEK SERVICE

- LOWER COMMUNICATION COSTS;

- CALL

PARAMATER SELECTION TO SUIT PARTICULAR APPLICATIONS.

CALL OUR TELEMARKETING STAFF AT 1-800-268-9102 FOR MORE

INFORMATION ABOUT UTILIZING THIS SERVICE AND SERVICE FEATURES.

-

DATAPAC FAMILY OF SERVICES

DATAPAC 3101


DATAPAC 3101 IS A NETWORK ACCESS SERVICE WHICH ENABLES TELETYPEWRITER

COMPATIBLE DEVICES, SUCH AS TIME-SHARING TERMINALS, TO ACCESS THE

DATAPAC NETWORK.

LOW SPEED, ASYNCHRONOUS DEVICES ARE SUPPORTED THROUGH AN INTERACTIVE

TERMINAL INTERFACE (I

TI) IN A PACKET ASSEMBLER/DISASSEMBLER (PAD),

WHICH ALLOWS THE DEVICES TO ACCESS THE NETWORK OVER DIAL-UP (DDD)

OR DEDICATED ACCESS LINES.

ITI, THE END-TO-END PROTOCOL FOR DATAPAC 3101 CONFORMS TO THE CCITT

RECOMMENDATIONS X.3, X.28 AND X.29 AND SUPPORTS ACCESS TO THE

DATAPAC NETWORK FOR ASYNCHRONOUS, START-STOP CHARACTER MODE TERMINALS.

X.3 SPECIFIES THE OPERATION OF THE PAD. IT CONTAINS THE SPECIFICATIONS

FOR THE TWELVE INTERNATIONAL PARAMETERS AND THEIR OPERATION. ADDITIONAL

DOMESTIC PARAMETERS ARE A

LSO IN PLACE TO MEET CANADIAN MARKET REQUIREMENTS.

X.28 SPECIFIES THE COMMAND LANGUAGE BETWEEN THE TEMINAL AND THE PAD.

IT ALSO SPECIFIES THE CONDITIONS WHICH DEFINE THE COMMAND MODE AND

THE DATA TRANSFER MODE.

X.29 SPECIFIES THE PROCEDURES TO BE FOLLOWED BY AN X.25 DTE TO

ACCESS AND MODIFY THE PARAMETERS IN THE PAD AS WELL AS THE DATA

TRANSFER PROCEDURE.

THE USER NEEDS NO SPECIAL HARDWARE OR SOFTWARE TO INTERFACE A

TERMINAL TO THE DATAPAC NETWORK. A KNOWLEDGE OF THE ITI PROCEDURES

IS THE ONLY REQUIREME

NT AT THE TERMINAL END.

THE DATAPAC 3101 SERVICE PROVIDES FOR TERMINAL TO HOST (USER'S

COMPUTER) AND TERMINAL TO TERMINAL COMMUNICATION. THE HOST ACCESS

SHOULD CONFORM WITH THE X.25 PROTOCOL, USING THE DATAPAC 3000 ACCESS

SERVICE, AND ALSO SUPPORT THE HIGHER LEVEL PROTOCOL CONVENTIONS OF ITI.

HOST ACCESS MAY ALSO BE PROVIDED VIA THE DATAPAC 3101 SERVICE FOR SOME

APPLICATIONS. THE DATAPAC 3101 SERVICE ALSO PROVIDES BLOCK MODE AND TAPE

SUPPORT.

DATAPAC FAMILY OF SERVICES

D

ATAPAC 3201


NETWORK ACCESS SERVICE WHICH ENABLES VARIOUS TERMINALS

THAT ARE BUFFERED, POLLABLE AND OPERATE ASYNCHRONOUSLY TO COMMUNICATE WITH

HOST COMPUTERS THROUGH THE DATAPAC NETWORK.

APPLICATIONS


THE DATAPAC 3201 SERVICE IS TYPICALLY USED BY THE GENERAL MERCHANDISE AND

SPECIALITY SECTORS OF THE RETAIL INDUSTRY IN CANADA. IT PROVIDES A COST

EFFECTIVE COMMUNICATION SOLUTION WHENEVER THERE IS A REQUIREMENT FOR

SENDING SMALL AMOUNTS OF INFORMATION TO A HOST COMPUTER AND OBTAINI

NG A

SHORT RESPONSE. THE PRIMARY APPLICATIONS ARE ON-LINE COMPILATION OF

SALES DATA TO HELP IN INVENTORY CONTROL, AND ON-LINE CREDIT VERIFICATION

TO DETECT FRAUDULENT CREDIT CARDS. OTHER EMERGING APPLICATIONS INVOLVE

TRUST COMPANIES, CREDIT UNIONS, BANKS AND SERVICE STATIONS.

ACCESS ARRANGEMENTS


DATAPAC 3201 PROVIDES SUPPORT AT THE CUSTOMERS' TERMINAL END (FOR EXAMPLE

A RETAIL STORE) BY MEANS OF A PACKET ASSEMBLER/DISASSEMBLER (PAD) WHICH IS

LOCATED IN A TELECOM CANADA MEMBER COMPANY

CENTRAL OFFICE. THE PAD

POLLS THE VARIOUS DEVICES FOR INFORMATION IN AN ON-LINE REAL TIME

ENVIRONMENT.

DEVICES MAY COMMUNICATE TO THE PAD VIA TWO OPTIONS:

1) SHARED MULTIPOINT MULTIDROP ACCESS AT 1200 BPS, OR

2) DEDICATED ACCESS AT 1200, 2400 BPS.

PROTOCOL SUPPORT


COMMUNICATION BETWEEN THE PAD AND THE TERMINAL CONFORMS TO THE ANSI

(AMERICAN NATIONAL STANDARDS INSTITUTE) X3.28-1976 ISO (INTERNATIONAL

STANDARDS ORGANIZATION) POLL/SELECT ASYNCHRONOUS PROTOCOL. TELECOM CANADA

UNDERTAKES T

O TEST TERMINALS WHICH SUPPORT THIS PROTOCOL, PRIOR TO

CONNECTING THEM TO THE DATAPAC 3201 NETWORK. FOR MORE INFORMATION REFER

TO THE "RAPID TERMINAL COMMUNICATION PROTOCOL" SPECIFICATION.

COMMUNICATION BETWEEN THE CUSTOMERS HOST COMPUTER LOCATION AND THE

DATAPAC NETWORK IS ACCOMPLISHED BY THE USE OF A X.25 (DATAPAC 3000)

INTERFACE WHICH SUPPORTS THE DATAPAC 3201 HOST TO PAD "POINT-OF-SALE

(POS) END TO END PROTOCOL" SPECIFICATION.

COMMUNICATION RESPONSE TIME


- DATA COLLECTIO

N: AVERAGE 1.7 TO 2.3 SECONDS IN THE PEAK PERIODS.

- INQUIRY-RESPONSE (CREDIT CHECK): AVERAGE 2.7 TO 4.2 SECONDS IN

THE PEAK PERIODS.

MESSAGE SIZE


A TYPICAL RETAIL DATAPAC 3201 APPLICATION USES SHORT INPUT AND OUTPUT

MESSAGES. (FOR EXAMPLE AN AVERAGE OF 50 CHARACTERS). ONE KILOPACKET

(1,000 PACKETS OR 256,000 BYTES) IS EQUAL TO APPROXIMATELY 1,000 SALES

TRANSACTIONS OR 500 CREDIT AUTHORIZATIONS. AVERAGE TRANSACTION VOLUME

WOULD BE LESS THAN 5000 PACKETS PER DAY.

OPTIONAL DATAPAC NET

WORK FEATURES:


CLOSED USER GROUP (CUG): ALLOWS DEVICES WITHIN ONE GROUP TO COMMUNICATE

                        ONLY WITH ACCREDITED DEVICES OF THE SAME GROUP,
                        RESULTING IN A HIGH DEGREE OF DATA SECURITY.
                        ADDITIONAL OPTIONS ARE AVAILABLE TO LIMIT CALL
                        ATTEMPTS BETWEEN CLOSED USER GROUPS OR WITHIN A
                        CLOSED USER GROUP.

REVERSE CHARGE CALL: ALLOWS A USER TO CHARGE A

CALL TO THE DESTINATION

                        ADDRESS

REVERSE CHARGE CALL

BLOCKING: REVERSE CHARGED CALLS DESTINED TO A DATAPAC 3201

                        ADDRESS WILL BE BLOCKED BY THE NETWORK.

Whew! I probably didn't get all of it, but hey, I'm lazy, and I am not

about to read through it all too see if it makes sense! <grin>

Your Phriend,

Lithium

Call: T h e NEW _ _ The Motor Inn | \ /\ || |_/

3/12/2400 Baud |/ /–\ | \ | \_ 24 Hours a Day

(403) 963-0658 / / \ | | |\ | / | |

Headquarters of the New Dark Council. | | | \|| | |

                          \__ \__/  |__| |  | \__ | |___

Phreaking is alive in 1990


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

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