What Is a Modem in Computer Networking? and Functions, One of the hardware needed to connect a computer to the internet is a modem. Not many people understand that the name of the modem itself stands for the process of how it works. Modems also have many types with their advantages and disadvantages. In this article, we will discuss the definition of the modem, modem function, modem types, and modem work.
The modem itself is an acronym of the Demodulator Modulator. That is, this one device can function as a modulator and also a demodulator. Modulator itself means that it converts information signals into carrier signals to send.
Meanwhile, the demodulator is a separator between the information signal and the carrier signal, so that a data can be received perfectly. Broadly speaking, modems can be divided into two types, namely internal modems, and external modems. Explanations of both are displayed in the following points:
1. Internal Modem
As the name implies, an internal modem is a type of modem that is installed directly in the CPU of a computer. If you notice, the shape is a card that is installed in one of the mainboard expansion slots, for example in a PCI or ISA slot. Some of the advantages of using an internal modem are that the price is more efficient, does not require a lot of space, and does not require an adapter, so it is more practical.
Even so, by using an internal modem, you cannot see the indicator that shows the modem status by the naked eye. The internal modem must also supply the power voltage from the CPU because it is connected directly to the device.
2. External Modem
Is a type of modem that is located outside the CPU. Usually, to connect this modem with a computer, it is done via a USB or COM port. One of the advantages of using an external modem is that it is flexible enough to be moved from one computer to another.
In addition, there is no need for an expansion slot to be allocated specifically to the modem. There are also indicators that make users understand and can monitor modem status. Even so, external modems are more expensive than internal modems and require a separate place to put them, even if they don’t need such a large place. There are various types of external modems on the market. When viewed from a wireless network system, for example, there are external modems such as GSM modems, CDMA modems, HDSPA modems, and HSUPA modems.
Modems have several functions so that a computer can be connected to the internet network. In general, a modem does have the main function of converting digital signals from computers into analog signals and vice versa, but modems also have other functions. Modem functions include:
- Turn digital signals into analogs and vice versa
- Connect a device (computer, laptop, etc.) to the network
- Translate signals with modulation and demodulation processes
- Check data packets to communicate
As mentioned earlier, there are various types of modems that you need to know, for example:
- Dial-Up Modem: to connect computers and internet networks via telephone cable. Internal and installed directly on the motherboard. When used, users cannot use the phone temporarily. Access speed is only 12-20 Kbps, but almost all PCs and laptops have dial-up modems installed.
- Cable Modem: a modem that can connect a computer with a cable TV connection. Download speed can reach 27 Mbps and upload speed can reach 2.5 Mbps upstream. Internet services are usually not restricted and payments are made every month. Although it includes a modem that costs a bit expensive, the access speed is not affected by peak hours.
- GSM modem: the modem that requires a GSM Simcard to work. Includes an external modem that must be installed into the computer port. Usually, many people use this modem for their laptops. Previously, the sim card must be topped up with data or data packets in order to be able to connect to the internet. GSM modems have a wide network coverage, it’s just that users can spend quite expensive subscription fees per month.
- CDMA Modem: A wireless modem that works on a CDMA network, which allows more than one signal to occupy a single transmission channel, thus optimizing the available bandwidth. The difference with GSM (which uses TDMA channels), CDMA does not set a specific frequency for its users. Each channel can use the existing full spectrum. The price of CDMA modems is more expensive than GSM, but cellular communication lines and data are separate, so connectivity is more stable.
How the Modem Works
The modem itself is actually a tool that allows one computer with another computer to communicate by translating the transmitted signal. Computers as hardware emit a type of digital signal, a signal capable of producing the appearance of images, documents, or programs. Meanwhile, internet telephone channels are devices that work with analog signal types.
Digital signals sent by a computer must first be converted into analog signals so that they are able to pass through telephone lines. As mentioned before, the modem is an abbreviation of modulator-demodulator. Modulation is the process of translating digital signals into analog, while demodulation is the process of translating analog signals into digital.
Such is the discussion about the understanding of modems, modem functions, and how the modem works. Indeed there are quite a number of types of modems on the market. Use it again to your needs. By weighing their advantages and disadvantages, you can determine what type of modem is the most optimal for connecting your PC to the internet network. Thank you for reading this article.