What is Modem in Computer Network?

Modem stands for Modulation Demodulation. A modem converts the digital data signals into analogue data signals. They can be installed within the computer in a development slot applicable for it.

There are frequently two types of Modems that are as follows −

Standard Modem

The standard modems use generic device drivers, and they can be internal and external ones. The internal modems do not need much physical structure. They can be installed into a compatible development slot. The external modem is connected through one of the COM port to the computer through a cable called a null-modem cable.

Window Modem

A window modem is a private plug and plays tool. It requires a particular device driver supported by the window operating framework to function correctly.

Features of Modems

The main features of modems are as follows −

• They have high uploading and communication rates. An X2 modem provides an uploading bandwidth between 28.8 to 56 Kbps.
• They are upgradeable through a software patch to meet almost any universal standard.
• They enable high-speed downstream data transfers by digitally encoding all downstream data while upstream runs at conventional rates of 33.6 kbps.
• Some modems incorporate dual simultaneous voice and Data (DSVD), i.e., they can carry both analog voices and computer data.
• They can detect callers originating telephone number, and thus they can serve as caller ID.
• Some modems provide advanced voice mail features, and those modems serve as intelligent, answering machines or digital information systems.

Types of Modems

There are the following types of modems which are as follows −

Optical Modem

Optical Modem uses optical cables instead of other metallic media. It converts the digital data signals into the pulse of light transmitted on the optical fiber used by it.

Digital Modem

A digital modem converts digital data into digital signals. It modulates the digital data on the digital carrier signals for transmission on digital transmission lines.

Acoustic Modem

The acoustic modem is a particular type of modem that can couple the telephone handset with a device used by traveling salespeople to connect the hotel phones. It contains a speaker and microphone.

Smart Modem

The smart modem allows auto-dial/redial and auto-answer capabilities. It contains a microprocessor onboard that uses the Hayes AT command set to provide auto-dial and auto answering functions.

Short Haul Modem

The short-haul modem is those who are present in your PC at home. They can transmit data over 20 miles or less, and generally, they are used to connect PCs in a building or office within this area.