- Internet users need a modem to connect to the internet because signals that comes from telephone and cable lines are analog, and computers can only process digital information.
- The modems takes the analog signal from the connection line and converts it into digital that the computer can read.
Types:
ADSL:
- It stands for Asymmetric Digital Subscriber Line.
- Standard twisted-pair telephone cable used for shot distances, carry signals with much higher frequencies than the cables maximum frequency rating.
- ADSL's performance gradually declines as the telephone cables length increases.
- This limits ADSL broadband service to subscribers within a relative short distance of the telephone exchange.
Cable Modems:
- It is a hardware device that allows your computer to communicate with an ISP over a landline connection.
- It converts an analog signal to digital signals for the purpose of granting access to broadband internet.
- Cable modem works by connecting a coaxial cable to jack in the wall and then a cat 5 cord from the modem to a computer or network router.
WiFi and WiMax:
- The WiFi and WiMax standards use wireless mobile broadband modems operating at microwave frequencies.
Mobile Broadband:
- Modems which use a mobile telephone system (GPRS, UMTS, HSPA, EVDO, WiMax..etc) are known as mobile broadband modems.
- It is also called as wireless modems.
- Wireless modems can be embedded inside a laptop or appliance, or be external to it.
- External wireless modems are connect cards. USB modems for mobile broadband and cellular routers.
Advantages:
- Get a high speed internet.
- Converts the analog to digital signals.
Disadvantages:
- DSL modems works better when you are closer to the provider's central office.
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