Conclusion On DSL Modems - Modem stands for Modulator-Demodulator.Sender performs modulation which means converting analog data into digital data while receiver performs demodulation which refers to converting digital data into analog one.Before choosing a good modem some issues need to be cleared.

I am thinking of changing my old DSL modem supplied by my ISP,because last month I took a fast internet connection & the modem I think is not compatible with it.Is it so that modems incite malware,trojan horses & viruses?I wanted to know.What do you suggest me?Should I stick to an old DSL or purchase a new one.

Some important points to be kept in mind about modem

• At the sender’s side,modem take electrical signals as input & converts them into sound or audio signals.At the receiver’s side,sound or audio signals are converted back to electrical signals.
• Since modems are directly connected to an internet so they cannot stop viruses, malware & any threat from entering inside our system.
• Modems come in various flavours of ADSL modems,cable modems & broadband modems.

Characteristics of ADSL modem

• ADSL stands for Asymmetric Digital Subscriber Line the transfers data faster over copper telephone lines than the conventional modem does.
• ADSL present some issues regarding installation,proper installation of frequency filters is necessary at the customer premises.This is needed to avoid interruption in the voice service.
• Most ADSL modems come attached with microfilters which can be easily attached with the subscriber’s phone & hence avoiding the rewiring at the customer premises.
• ADSL modem operates within the geographic range of 2 to 3 miles.
• ADSL modems supports downstream data rates are 1.5 to 9 Mbps while its upstream datarates are 16 to 640 Kbps.

Characteristics of Cable modems

• Cable modem is a technology used to work with cable TV lines.
• One technical difficulty with Cable modems is that, Cable TV system has been designed to broadcast signals only in one direction while internet requires 2 way transfer-upstream & downstream.
• This modem provides a data rate upto 2 Mbps.
• Cable modem presents 2 times faster download speed in comparision to 1.5 Mbps ADSL modems.While the upload stream of cable modem is same as ADSL modem.
• Cable modem offers cheaper rates at the set up price ranging from $50 to $100 while DSL has higher set up price of $150.Then monthly subscription prices of DSL modem are $5 to $10 more than $40 to $50 price of cable modem.
• Service providers generally provide security features in the hardware of the cable modem.While DSL modem provide better security with features installed in the hardware & software.

How you can use modem in your computer?

Modems can be used in your computer system through many types.Some of the ways are through USB,through ethernet & through a switch.

• USB Modem –
  • It refers to a small portable USB device connected to a computer via USB.It is quite similar to USB flash drive & it weighs only 25 grams.
  • One end of USB modem is connected to USB interface while the other is connected to RJ-11 connector to connect the telephone line.
  • USB modem needs no power supply & can be easily connected to any USB port or your laptop & desktops.
• Ethernet Modem –
  • It is a device which uses ethernet technology for connecting computer to an internet.
  • These modems are more reliable than USB modems in networking.
  • These don’t require the installation of device drivers while USB modem does.
  • It provides higher data rates of 100 to 1000 Mbps.
  • These can be reached to longer distances as compared to USB modems.
• Switch Modem –
  • ADSL modems can also be connected to switch & many computers can be connected to this.
  • For this enable the DHCP property from the modem.Now,remove RJ45 cable from the modem & connect it to switch.After that connect the computers to switch.

Choose to buy a new modem or use one provided by an ISP

• If you wish to use a modem supplied by your ISP then it has a plus point that it comes with a guarantee.If anything changes or damages,then ISP will have to replace it.This is not the case with buying a new modem.
• If you are attempting to buy a modem then it must be compatible with your ISP.Suppose if your ISP switches to different technology,then your new modem relaying on old technology will be unable to use new services.