Browse Prior Art Database

Transmission Network Testing

IP.com Disclosure Number: IPCOM000049370D
Original Publication Date: 1982-Apr-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Lenoir, B: AUTHOR

Abstract

Modem data transmission networks use fairly complex equipment with highly sophisticated program-controlled modems. Any failure of a modem or of any portion of the network may be dramatic and should be localized as rapidly as possible even though the network may not include any diagnostics facilities. This article describes low stand-alone diagnostic equipment.

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Transmission Network Testing

Modem data transmission networks use fairly complex equipment with highly sophisticated program-controlled modems. Any failure of a modem or of any portion of the network may be dramatic and should be localized as rapidly as possible even though the network may not include any diagnostics facilities. This article describes low stand-alone diagnostic equipment.

As shown in the figure, the equipment is essentially comprised of an emitter section and a receiver section to be connected to the network. From the network only one portion has been represented, comprising one local and one remote modem with data terminal equipment. More specifically, a connection is made to the local modem associated with (DTE) the link to be tested, through a conventional CCITT interface. The emitter section is provided with two programmable read-only memory (PROM) sections, while the receiver has a PROM and a RAM (random-access memory). A keyboard is also provided to control the different modes of testing. A LED (light-emitting diode) display is used for displaying the test results.

The keyboard is used by an operator to initialize a test command. Under this command, the emitter generates a test pattern in SDLC (Synchronous Date Link Control) procedure, as shown on the following page.

This pattern will be sent on a transmit data lead to the modem when the procedure will permit it, by using the "Test Control" lead.

The following tests may be available and a t...