The word modem is an acronym for MOdulator / DEModulator. Modems are used to send digital data signals over analog circuits. The modem uses the Public Switched Telephone Network (PSTN) and either PSTN for dial or private copper wires for leased line or private wire applications. A 2-Wire Facility is one that supports transmission in two directions simultaneously while mixing signals (Half Duplex) for 2-Wire Leased applications. A 4-Wire Facility is one that supports transmission in two directions but isolates the signals (Full Duplex) by Frequency, Time, and Space division plus other techniques that enable reflections to occur without causing the signals to mix together for 4-Wire Leased applications.

Modems are governed by the International Telecommunications Union – Telecommunications (ITU-T) Service Sector based in Geneva, Switzerland. The ITU-T sets the (V. Series) standards including V.92 / V.90 at 56Kbps, V.34BIS at 33.6Kbps, V.34 at 28.8Kbps, V.29 / V.27 at 19.2, 9.6 & 4.8Kbps, V.32BIS at 14.4Kbps, V.22 at 2.4Kbps, and V.23 at 1.2Kbps. There are also BELL standards still used such as BELL202T at 1.2Kbps and BELL103 at .3Kbps. Most modems today come with built in error correction, data compression technology based on ITU-T Industry Standards and are used in a wide range of applications.

ISDN Terminal Adapter, DDS Unit, T1/FT1 DSU/CSU, T1 CSU, DSL Router, and Cable Router are all called modems but technically don’t modulate or demodulate. The modems in this section all modulate and demodulate and meet with the ITU-T and BELL standards. The Security features found in some of the modems offer Password Protection, Call Guard, and Call Back Security Options.

At Data Connect, we offer a wide range of modem products to suite your network needs. We can assist you in finding a solution that maximizes your investment while providing the solutions that will benefit your customers both now and for years to come. With the ability to match all requirements and standards, your choice becomes a wise choice and made easy by Data Connect expertise.

 

Dial and Leased Line Modems