Internet connections explained, A guide to dial-up, ADSL and Cable connections.
Welcome to our guide to Internet connections.
In this section we will explain the pros and cons of the different Internet connections currently available for home users.
There are various connection types on offer from the different Internet service providers, your choice will depend on how often and how you intend to use the Internet.
are types of broadband connection, the term "broadband" only refers to the performance of an Internet connection, not to any particular type of connection.
The connection types in this section include:
- Dial-up Connections
- ADSL Connections
- Cable Connections
Dial-up connections are one type of Internet connection available from ISPs, they are the slowest and (usually) the most inexpensive.
A dial-up connection allows you to connect to the Internet via a local server using a standard 56k modem. Your PC literally dials (hence the name) a phone number (provided by your ISP) and connects to the server and therefore the Internet.
note: In the US the FCC passed a regulation limiting V90 dial-up connections to 53Kbps.
Once connected you can utilise all aspects of the Internet, the drawback with a dial-up connection is the speed. A standard 56k modem can theoretically transfer 56 Kilobits of data a second, this means that you can (again theoretically) transfer up to 7 Kilobytes a second (although to get a full 7k is near impossible due to the compression overhead).
When you consider that the average web page including its images is around 50 Kilobytes, this means it would take around 7 seconds for the web page to completely load in your browser.
On top of this, most (though not all) Internet service providers charge by the minute for your dial-up connection, so the longer it takes to load the pages you visit, the more you pay for your connection. The cost is usually the same as you would pay for a local phone call, so as long as they are used sensibly they can be a very cost effective Internet connection.
Dial-up connection Pros
Dial-up connections can be very economic and are widely available, the cost per minute is comparable to that of a local phone call, or priced as a monthly plan which will include a certain amount of time. As these connections use a standard modem the hardware costs are minimal, most modern laptops have a built-in 56K modem.
The fact that you only need a standard phone line to connect makes dial-up connections great for when you are on the move, especially if you find yourself in a location without a WIFI connection point.
Dial-up connection Cons
Dial-up connections are very slow compared to other connection types. When connected to the Internet the same phone line cannot be used for phone calls, so if anyone phones you when you are connected they will get the busy signal and you may be disconnected from the Internet.
Dial-up connections transfer data over an analogue line so before the data is sent it has to be converted from digital to analogue, likewise when data is received it has to be converted from analogue to digital (this is what the modem does). This adds a performance overhead which affects the speed of the connection.
ADSL (Asymmetric Digital Subscribers Line) connections are becoming more and more widely available and can provide an excellent Internet connection.
The connections work by splitting your phone line into two separate channels, one for data (Internet) and one for voice (phone calls), which means you can talk on the phone and be connected to the Internet at the same time.
You will often see ADSL connection services advertised as having different speed specifications, below are some common configurations:
Notice there are two values to each configuration, the first figure states the download speed and the second figure is the maximum upload speed.
As an example let's take the second configuration 512Kbps/128Kbps
, this means that you can potentially
download data at a speed of 512Kbps and upload data at 128Kbps.
The most important figure is the download speed, this depicts how long it will take to view a web page, download a music file or an email attachment
As an example of how the different download speeds can affect your connection, below are some figures to give you an idea of the differences:
Average Web Page (50 Kilobytes including images)
Average MP3 file (music file) (4 Megabytes)
- 256Kbps download speed - roughly 1.56 seconds to view page.
- 512Kbps download speed - roughly 0.78 seconds to view page.
- 1Mbps download speed - roughly 0.39 seconds to view page.
- 2Mbps download speed - roughly 0.195 seconds to view page.
- 8Mbps download speed - roughly 0.048 seconds to view page.
- 16Mbps download speed - roughly 0.024 seconds to view page.
- 256Kbps download speed - roughly 2 minutes and 8 seconds to download.
- 512Kbps download speed - roughly 1 minute and 4 seconds to download.
- 1Mbps download speed - roughly 32 seconds to download.
- 2Mbps download speed - roughly 16 seconds to download.
- 8Mbps download speed - roughly 4 seconds to download.
- 16Mbps download speed - roughly 2 seconds to download.
The figures above are only theoretical
, as there are many other factors which determine the real
download speed, such as the speed of the server/host you are downloading from.
ADSL offers incredible performance compared to standard dial-up connections and is becoming the first choice of broadband for most Internet subscribers.
Most ISPs that offer ADSL packages charge a flat monthly fee, which normally
includes a certain amount of bandwidth each month. The bandwidth refers to how much data (web pages, music, videos, etc) you can download per month without incurring additional charges from your Internet service provider.
ADSL connection Pros
Apart from the obvious speed advantages that ADSL connections offer, ADSL technology eliminates the need for a second phone line by allowing voice and data transfer at the same time (you can use the phone as normal while connected to the Internet).
Because ADSL transfers data digitally it eliminates the usual performance overhead associated with standard dial-up connections, in other words ADSL doesn't need to convert the data from digital to analogue and back again.
ADSL connections are Always on, which makes the usual long wait to connect a thing of the past.
ADSL connection Cons
ADSL connections are not available to everyone, you should always ensure that you have ADSL coverage in your area (an ISP will check for you). The hardware costs can be quite significant as you will need a special ADSL modem and ADSL filters to use the service. Most ISPs allow you to hire these items which can reduce the initial cost.
Because ADSL connections are Always on you will need a firewall to protect your PC.
Cable connections are considered one of the best types of Internet connection available to the home user, they offer very fast and reliable connections with a fixed monthly fee.
Cable companies usually offer different packages to suit different Internet subscribers, your choice of package, as with all Internet connections, will depend on how you intend to use the Internet.
The different packages will offer different speed specifications and bandwidth limits.
Because a cable connection uses a totally separate medium to transfer data, it doesn't affect your ability to make/receive phone calls when connected to the Internet.
Cable connection Pros
Speed is a major reason for having a cable connection, with very high speed packages available it is an excellent choice for those who don't like to wait around tapping their fingers when downloading big files such as music or large attachments.
Like ADSL connections, cable connections transfer data digitally, eliminating any digital/analogue conversion overhead.
Cable connections are Always on, eliminating long waits to make a connection and start surfing the web.
Cable connection Cons
Cable connections are not available in every area, you will need to contact the cable company of your choice to ensure that you have coverage.
Because cable connections are Always on you will need a firewall to protect your PC.