What is a modem? Functions of Modem

Similar to Routers, Modems are indispensable devices for computer and mobile phone users who want to use the internet to meet their needs. So what specifically is a Modem? What are the differences with Routers? How many types of Modems are distributed on the current market? Let's find out details with TipsMake through the article below.

What is a modem?

Modem 's full name is Modulator and Demodulator , also known as Modem . This is a device that has the function of modulating analog signals for the purpose of encoding digital data. At the same time, the device also performs the function of demodulating network signals to decode digital signals.

Simply put, Modem devices can convert digital information in internet-connected devices such as phones and computers into analog signals transmitted through wires. On the contrary, Modem also translates analog signals into digital data so that devices such as phones and computers can understand.

What is a modem? Functions of Modem Picture 1

Distinguishing Modem and Router (Router)

Although both Modem and Router are devices that connect computers to the internet. However, between the two devices there are quite a few differences. As follows: 

1. Mechanism of action

The first difference is the operating mechanism. For: 

1. Modem: Can operate independently by connecting with a wired computer device, mobile phone, etc. to convert digital signals into analog signals. 
2. Router: Works by examining information packets, verifying the packet path, and routing those information packets to successfully transmit information to destination devices.

In short, the difference between a Router and a Modem is through a simple operating mechanism: the Router performs the task of streaming information packets and assigning IP addresses to devices that need to be connected in the network system.

What is a modem? Functions of Modem Picture 2

The transmitted information (in copper cables, fiber optic cables) is analog (this is a continuous form of information). This transmitted information is in a different format than the pre-existing digital format of 0 to 1 in the user device. Therefore, it is necessary to equip an additional device to help convert information between these two devices.

The information packets that users transmit will be converted from digital to analog form by the Modem for transmission in the internet space. On the contrary, when the information packet is transmitted from cyberspace back to the user's device, the modem will be responsible for converting from analog to digital form so that computers and mobile phones can read and understand that information.

2. Connection location

The next difference is in connection location. Specifically:

1. Modem: This is a device that connects directly to the network operator via fiber optic cable, copper wire, etc. Or it can be connected wirelessly by radio waves. 
2. Router: Router is installed between the Modem device and the network system. The network here is a collection of computer devices or between a computer and a switch, etc. The Modem and Router devices will be physically connected to each other. Devices connected to the Router can access the internet through the Modem.

What is a modem? Functions of Modem Picture 3

The Router is equipped with Gigabit and Ethernet connection ports to connect to other devices and network systems. Commonly used today are Routers that use Wifi to connect wirelessly.

Between the Modem device and the Router, it is sometimes integrated into a device called a 'Wifi device' . This device can be directly plugged into the fiber optic cable provided to the user by the network operator. However, this Wifi also has the disadvantage of relatively limited Wifi broadcasting ability. Therefore, users need to buy a separate Router device to make the most of the bandwidth. 

3. Connection mode

The final difference is in connection mode.

1. Modem: This device has 3 physical connection modes. Specifically, Half Duplex, Full Duplex, Full Duplex, 4 wires and 2 wires. 
2. Router: This device also has 3 connection modes: User Execution, Global Configuration and Administrative. 

What is a modem? Functions of Modem Picture 4

Although there is a difference between these two devices in connection mode. But sometimes the Modem and Router are integrated into one device. This is the Modem contained inside the router, allowing connection between multiple computers or devices in a local area network (also known as LAN) and the internet wide area network (WAN). 

This is also a technology that is quite commonly used today, making network setup easier and does not require too many separately connected Modem and Router devices. 

Functions of Modem

As mentioned, the Modem's main function is to modulate signals similar to digital information from internet-connected devices provided by network operators (computers, phones) and convert it into digital signals. analog signal to transmit over wire. In contrast, Modems are responsible for translating analog signals into digital data so that devices (computers, phones) can understand. 

What is a modem? Functions of Modem Picture 5

In addition to performing the above main functions, there are also some additional uses of Modem as follows:

1. Data Compression. This is a function that reduces the amount of time it takes to send data and reduces data errors in the signal.
2. Control network traffic.
3. Data transfer and backup.
4. Perform remote management.
5. Fixes. With the following information transmitted between Modem devices. Sometimes, problems occur during the transmission process, causing this piece of data to change or be deleted. If this happens, Modem users need to use the error correction feature to fix it.  

Modem advantages and disadvantages

Modem is a very important device so that users can use devices to access the internet. Not only that, this device also provides users with many outstanding advantages, supporting many more convenient features. Specifically: 

1. Advantages

The advantages that Modem brings to users in the process of connecting and using the internet to communicate and transmit data signals are as follows:

1. Modem is a device used to convert transmission signals quickly and effectively.
2. Has high internet transmission speed.
3. Providing users with many internet packages with flexible fees, suitable for many different uses of each user. 
4. There are some Modems that are fully compatible with Fax technology. Through Modem, fax messages can be transmitted and received instantly.

What is a modem? Functions of Modem Picture 6

2. Disadvantages

Along with the outstanding advantages that popular Modem devices bring to users. At the same time, this device also has certain limitations such as:

1. Can make users' computers vulnerable to malware containing intrusive viruses or to the influence of disruptive hackers. However, as a way to prevent these things, Modem and router manufacturers have built and integrated firewalls to protect data. In addition, not only firewalls and security software are also used for this purpose. 
2. The upgrade process is difficult and depends heavily on the ISP network service provider.
3. Lack of portability in externally provided Modem lines.
4. Connectivity is unavailable in rural or remote areas for DSL Modem devices.  

What is a modem? Functions of Modem Picture 7

Classification of Modems on the market

On the market today, many types of Modems are used and distributed. In general, Modems are classified into 4 main types based on the following factors:

1. Based on Directional Power

For classification based on directed power, Modem has 2 operating modes. Specifically:

1. Half Duplex mode: At a time, half-duplex modem only allows signals to travel in one direction. If a Modem is detected on the transmission line, the service provider's signal will be transmitted to the DTE through the control signal of the digital interface. 
2. Full Duplex mode - Full Duplex: Full duplex modem allows signals to be transmitted in both directions. Because each direction has a separate physical path. Therefore, with the same wave frequency, it can be used to transmit signals in both directions. 

2. Based on Connect to line

For modem device classification factor based on connection to the line. This device is specifically divided into two specific types as follows:

1. 4-wire Modem: For a 4-wire Modem connection, there will be one pair of wires used for the outgoing carrier wave and the other pair of wires will be used for the incoming carrier wave. This means that, at the same frequency, the device is used to transmit signals at both ends of the wire.
2. 2-Wire Modem: With 2-Wire Modem, the device uses the same pair of wires for outgoing and incoming service providers. 

What is a modem? Functions of Modem Picture 8

3. Based on Transmission Media

Classified based on transmission media, there are 3 types of Modems used to transmit signals specifically as follows:

1. Radio Modem: This type of Modem is used to send information data through a pair of glasses, a radio frequency signal.
2. Optical Modem: This is a Modem that works by using light to perform the task of transmitting data to a pair of glass fibers. Such Modems often apply different technology than Modems that operate on specialized wires.
3. Dial-up modem: This type of modem contains an electrical circuit that simulates a telephone. This means that this Modem can simulate picking up the phone and dialing a number or hanging up the phone.

What is a modem? Functions of Modem Picture 9

4. Based on Transmission Mode

Finally, with the classification based on transmission mode, there are 2 specific types of Modem as follows:

1. Synchronous Modem: This type of Modem can continuously process a stream of data Bits, however, processing requires a clock signal. For synchronous transmission of data Bits, the internal clock of the DTE device can be used and provided to the Modem with the same clock. 
2. Asynchronous Modem: This type of Modem can handle data bytes and start and stop bits. Besides, the internal timing pulses are also synchronized with the leading edge of the starting pulse in the repeating direction.

Epilogue

Above is detailed information about what a Modem device is that TipsMake shares with you. In general, this device is very important in the process of users using the internet. Modem helps convert signals to the device being used quickly, bringing high efficiency to users. Thank you for following the article.

Micah Soto

Update 03 October 2023