High-speed dial-up services aim to accelerate traditional dial-up internet connections by reducing the amount of time spent on handshakes between devices and servers. They do this through acceleration servers that handle requests and caching on behalf of users, reducing redundant transmissions. Common file types like text can see compression rates over 50% while images may shrink by 50-90%, decreasing load times. Pop-up blocking and caching of popular pages also conserve bandwidth. Testing of one high-speed dial-up provider found homepage load times were up to three times faster than traditional dial-up. These techniques help prolong the viability of dial-up internet for those not ready for broadband.

1. How High-speed Dial-up Works
1.Introduction to How High-speed Dial-up Works
Surfing the Internet, do you find yourself going to get a cup of tea, a comic or clean your
bathroom between page loads? There are chances are you're using a dial-up connection, and a
sneaking suspicion may be growing on you; eventually , is your connection actually getting
slower? Sometimes, the connection speed of dial-up is limited by the bandwidth of Phone lines.
But, at the same time, the average file size for Web content is getting larger and larger. So Web
sites feel more comfortable bulking up their pages. It takes a lot time to squeeze all of that data
through a dial-up connection. New technology offers a solution to the slow-down that doesn't
necessitate broadband. Services like NetZero and EarthLink are now offering "high-speed
dial-up.“ According to advertisement for these services, you can get connection speeds that are
five times faster than traditional dial-up service. High-speed dial-up providers can't do anything
about the modem handshake, but they can speed up the software handshake.

2. 2. High-speed Dial-up: Acceleration Servers
The standard software handshake is usually a simplified explanation, of course, but you
can get the idea of the back-and-forth that need to occur in the handshake protocol before
information can be sent or received. High-speed dial-up providers have cut down on
this back-and-forth by creating a system that allows the conversing machines to remember
responses to questions. This makes for a much shorter conversation. This shorter
handshake equals much faster connection times. The increase in speed varies by machine,
but in some cases it can reduce the handshake by up to 50 percent. What might take 45
seconds with a "normal" dial-up service becomes maybe a 30-second process with a
high-speed service.
When you search for a Web page on the Internet, your request is routed though your ISP
to the Web. After making a series of stops along the way at machines that help find the
page you're looking for, your machine is connected to the computer that serves the Web
page you requested. When you search for a Web page using high-speed dial-up, your
request is sent from the dial-up modem in your computer to the ISP's acceleration server.
Now the acceleration server is requesting and serving pages on your behalf. The
acceleration server uses a broadband connection to quickly search the Internet for the
server that hosts the page you're looking for. Once it finds that server, the two machines
start talking and exchanging the information you need. Your ISP's acceleration server takes
that information and sends it to your machine

3. 3. High-speed Dial-up: File Compression
You know that there are two types of file compression that is the Key element of
high-speed dial –up Internet. Text and other files that need to remain perfectly intact
during the compression process use lossless compression. Once they are uncompressed,
the files return to their original state. When these files are uncompressed, they are not
exactly as they were before compression. They have lost some of the original data in the
process. The loss in quality may not be important to the user when weighed against the
increase in speed gained through the compression process.
Eventually, 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. I will describe three examples is text, image and other files.
At text files ・・・ Typically, text will compress at least 50 percent using on-the-fly techniques.
At image files ・・・ Typically, the image file size shrinks anywhere from 50 percent to 90
percent in the process.
At many other files ・・・ It is not possible to compress the file any further in a quick way.
In the case of secure Web pages, we already discussed why they cannot be compressed.
The acceleration server will not touch these files -- it just passes them through something.

4. 4.High-speed Dial-up: Filtering and Caching
If you type a URL into the address bar of your browser, you are sending a request for a
specific page. 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.
When you 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.
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. So instead of asking the
HowStuffWorks server thousands of times a day, it just asks once. Then it stores the page
in its memory, and every time another subscriber asks to see that, 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.

5. 5.High-speed Dial-up: The Bottom Line
We decided to try out one of the more popular high-speed dial-up providers to see how
much the service sped up a dial-up connection. After signing up for the service and
choosing the "out of the box" settings, HowStuffWorks tooled around the Web with both
normal and high-speed dial-up connections to test the difference in speed. After log-in, we
surfed repeatedly to some of the most popular sites on the Web. The results varied by site,
but as an example, HowStuffWorks came up three times faster with high-speed dial-up.
For the complete results, see the chart below.
It would seem that a clever combination of fairly straightforward technologies has helped
to overcome some of the speed bumps of dial-up Internet. These advances serve to prolong
the life of dial-up Internet and provide an alternative for those who are tired of standard
dial-up but not quite ready for the leap to broadband. If these advances continue, dial-up
may be here to stay for quite a while. For more information on high-speed dial-up and
related topics, check out the links on the next page.

6. 6. Lots More Information
How WiFi Works ・・・ WiFi has a lot of advantages. Wireless networks are easy to set up and
inexpensive. They're also unobtrusive -- unless you're on the lookout for a place to use your
laptoｐ, you may not even notice when you're in a hotspot. In this article, we'll look at the
technology that allows information to travel over the air. We'll also review what it takes to
create a wireless network in your home.First, let's go over a few WiFi basics.
How DSL Works ・・・ When you connect to the Internet, you might connect through a regular
modem, through a local-area network connection in your office, through a cable modem or
through a digital subscriber line (DSL) connection. DSL is a very high-speed connection that
uses the same wires as a regular telephone line.
How Modems Work ・・・ In this edition of HowStuffWorks, we'll show you how a modem
brings you Web pages. We'll start with the original 300-baud modems and progress all the
way through to the ADSL configurations!
(Note: If you are unfamiliar with bits, bytes and the ASCII character codes, reading How Bits
and Bytes Work will help make this article much clearer.)