Modem Type

1. Modem Dial-up (Modem Phone)
Phone modem to work with the wireline telephone network. The speed of the phone modem is varied. For a minimum requirement on residential Internet access, connections with dial-up modem is sufficient. Installation of the modem dial-up this process easier and lower cost. To be able to subscribe to the Internet with dial-up modem can contact your ISP (Internet Service Protocol).

Type of dial-up modem on the market is comprised of an internal modem and external modem. Internal modem is installed on the mainboard expansion slots, while an external modem attached to the computer using a serial data cable or USB data cable.

In Indonesia, some ISPs may serve Internet services with dial-up modem, including Telkomnet, Indosatnet, Wasantaranet, and CBNnet. For now, the dial-up internet access can be done directly with telkomnet @ instant. When you have a phone line from PT. Telkom can do the configuration or settings by providing dial-up modem.

2. Cable Modem
Cable Modem (Cable Modem) is the hardware that connects your PC with a cable TV connection. Cable modems have a way of working that resembles the workings of the Network Interface Card (NIC) or an ethernet card installed on your computer to a Local Area Network (LAN). The difference between the workings of a modem with an ethernet is the distance problem. Modem is not affected by distance, although only has a speed of about 50 Kbps, while on ethernet which has a speed of about 10 or 100 Mbps can only be within a maximum distance of approximately 1 km. Cable modem speeds range from 3-56 Mbps, and can work within a distance of 100 km more. Working process of the cable modem is separate from cable TV signal into two, namely the signal for television and data signals are connected to a cable modem. Both signals will not interfere with each other. Then, the cable modem connected to a network card Network Interface Card contained in the PC. Data rate downstream (incoming signal) averaging around 4-56 Mbps. While the upstream speed (signal exit) ranges from 256 Kbps to 3 Mbps.

Although the content of cable modem is different, basically now its contents as illustrated in the following diagram:

Tuner: the menguhubungkan directly into the CATV channel, typically using a diplexer to allow transmission of entry and exit through the same tuner. Tuner should be good enough quality to receive digital QAM modulated signal.
Demodulator: IF the incoming signal received by demodulator which normally consists of translating Analog to Digital.
Burst modulators: send the signal out through the tuner, Digital to Analog translator.
MAC: Media Access Control, assigned to perform ranging protocol is very similar to the satellite.
Interface: can be Ethernet, PCI bus, USB, or the other.

3. DDSL Modem
Currently, DSL (Digital Subscriber Line) is the main competitor cable modem. In terms of speed and cost does not vary much with the cable modem. Technology for the new DSL modem available is ADSL (Asymmetric Digital Subscriber Line). In Indonesia, not all areas covered by DSL technology. ASDL uses existing telephone cable network in the upgrade or have a particular enhancement. ADSL does not require a second phone line but need a splitter for the division between the modem and telephone. You can call at the same time when connected to the Internet through a single phone line. This is possible because the system on a phone line that can differentiate between high-frequency data transmission and voice transmission at low frequencies. This system still requires its own internet service provider, and in general there is a special collaboration between the telephone network providers and internet service providers. ADSL speed is not too much different from the cable modem, where the maximum downstream speed of 1.5 Mbps, and upstream speeds ranging from 64 Kbps. ADSL technology will develop a modem with a speed of 52 Mbps, about 50 times better than they are now.

4. Voice Modem
Voice modem is a term commonly used to describe an analog telephone data modem with a built-in ability of transmitting and receiving voice recordings through the telephone line. Voice modem is used for phone and answering machine applications. Similar to the Hayes command set of data used for the modem, where the host PC modem commands through a series of commands, known as AT commands, then there is a well-defined set of Common AT commands are somewhat consistent sound throughout the industry.

Source: Articel Wekekek's