The offers that appear on this site are from companies from which DecisionData. If you used the internet in the s, you might remember the sound of your dial-up internet service connecting. At the time, the 56 Kbps speed was cutting-edge technology, even if it tied up the home phone line in the process. In fact, dial-up internet is still available from a handful of providers and might even be the ideal internet service for some users.
But dial-up internet uses the existing phone line to connect you to the internet. This typically requires the installation of software specific to the internet service provider, traditionally acquired by CD, but these days often available via a web download.
When the computer is successfully connected, it keeps the connection open to allow you to send and receive data until you terminate the connection. For this reason, dial-up internet providers typically bill by time spent online.
Dial-up internet uses frequencies between and 3, hertz to translate the 0s and 1s that make up digital data. File compression is an evolving technology, and it doesn't work on every file type yet. The below information will help you understand what will and will not be accelerated by high-speed dial-up.
At this point, the on-the-fly file compression utilized in high-speed dial-up can't be added to the file types specified above because of the nature of the data. For instance, data on secure Web sites is encrypted. When it is transmitted, the code looks like a bunch of gibberish so that no one can read it.
When this gibberish reaches the acceleration server, it can't compress the code: If the compression software were to change even one character in the encrypted transmission, that would render the data unusable. In the next section, we will learn how high-speed dial-up accelerators filter out useless data to increase speed.
When you type a URL like www. If that page uses pop-up advertising, there are pop-up parameters hiding in its programming code. When the information is sent back to your machine, the hidden code executes a program that launches the advertisement. In order for the pop-up to pop, that hidden code must display parameters that tells your machine what size the ad is, where on the screen it should appear, and other details about the ad.
These ads take up valuable bandwidth, slowing down the transmission of data to your machine. To combat this drag, high-speed dial-up providers have bundled a pop-up blocker into the software they send to subscribers. This pop-up blocker is programmed to recognize those lines of code that spell out the ad parameters. When it sees those tell-tale lines of code, it rejects the ad's request to be displayed.
What this amounts to is less information being sent across the phone line to your machine. The less data that is sent, the faster the load time. The first time your browser loads a Web page, it has to load the entire thing, along with all of the images it displays.
If the browser saves the images and text, then the second time it loads the same page it can check for duplicates. If an image has not changed, there is no need to download it again. This process of saving a file in the hopes of reusing it in the future is called caching.
For a complete explanation of the caching process, see How Caching Works. High-speed dial-up uses a similar system for commonly requested Web pages.
Instead of constantly requesting the same page, the acceleration server takes note of which Web pages are being commonly asked for by all subscribers. Then it stores the page in its memory, and every time another subscriber asks to see HowStuffWorks, it simply transmits the page out of its memory to the user.
This is called server-side caching , and it saves time by eliminating redundant requests. There is a second side to caching -- client-side caching. Internet browsers like Explorer or Netscape are made to cache frequently viewed pages to cut down on load times. The browser stores the cached pages on your computer's hard disk. High-speed dial-up software enhances this feature. In addition to storing frequently viewed pages, it also looks for elements in those pages that remain constant.
For instance, instead of caching the entire HowStuffWorks homepage, most of which changes every day, it looks for things that don't change. On our homepage, the logo, the header, the navigation, and the search bar stay the same every day. The software makes note of that consistency, saves those elements, and then only loads what has changed every time you come to the HowStuffWorks homepage.
Here are the facts you need to know:. While broadband services such as DSL, cable modems, and satellite Internet are rapidly becoming available to more areas around the nation, dial-up networking continues to grow. It's estimated that wireless connectivity will pose the biggest challenge to dial-up networking in terms of subscribers sometime in the future. But analysts predict that, as of the end of , more than twice as many people will continue to use dial-up networking than will use broadband services to connect to the Internet.
In the gap will close, but dial-up networking will still be the most popular method by one and one-half times. Dial-up networking is the simplest way to connect to the Internet: You just connect over the phone line using your modem, once you've subscribed to an ISP. For the most part, the software tools you need come built into Windows; some ISPs, such as ihug, furnish a user interface that makes setup even easier.
Whichever method is used, dial-up customers usually only need to enter a user name and password, as well as the ISP's phone number, into a dialog box. The dial-up networking software uses that information to make the connection with the ISP and does all the rest of the work. After the initial setup, all that most customers need to do to make a connection is double-click an icon. When you initiate the process, dial-up networking first directs your modem to dial the ISP's phone number, which is answered by another modem at the other end.
For a few seconds the modems send control signals back and forth to determine how fast each can connect. The familiar screeching you hear when your modem first connects is the sound of your modem and the ISP's modem harmonizing the connection and deciding on a speed to use.
Once the connection is established, your modem silences its internal speaker, and dial-up networking sends your user name and password to the ISP using a process called CHAP - the challenge handshake authentication protocol. At the ISP's end, a computer checks your user name and password against a database of active customers. Once the ISP authenticates your information, the dial-up networking status window disappears, and you are free to surf, check and send e-mail, download files, and so forth.
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