THE JOURNAL OF EDUCATION, COMMUNITY, AND VALUES
by Jesse Snyder <snyderjw@pacificu.edu>
Senior, Computer Science Major at Pacific University
Webmaster for the Berglund Center for Internet Studies and the Matsushita Center for Electronic Learning
- .01. Introduction
- .02. Internet Talk
- .03. Tried and True: Dial-Up Service
- .04. Dial-Up's Distant Cousin: DSL
- .05. DSL's Enemy: Cable Modem
- .06. ISDN: A Special Kind of Broadband
- .07. T-1, T-3, and Even Bigger
- .08. Conclusion
.01. INTRODUCTION (Return to Index)
There are more people are getting on the Internet everyday. Some people connect at work, home, school, or even all three. There are a number of way people can get wired, each having benefits and disadvantages over other connection methods. First, we'll cover some Internet lingo you might hear and give it some meaning. Not sure what "kbps" is? This is the article for you. We'll also outline some of the more common ways of getting connected to the Internet, giving the pros and cons of each.
.02. INTERNET TALK (Return to Index)
This first section is to get a handle on some words that may be thrown around when talking about different ways of connecting to the Internet. Some of these are paraphrased from <http://www.webopedia.com>
Kbps (Kilobits per second): This is a measure of data transfer speed. If you are using dial-up modem, you get about 56 Kbps. This means that on average, every second you are connected, your modem will send 56 thousand bits every second. This really isn't very fast. If a web page contains 5 K (kilobytes, not bits) of text, and one kilobyte is 1024 bytes, then a web page contains 5120 bytes * 8 bits (8 bits in a byte) = 40960 bits, or roughly 40 kilobits. Thus, a web page containing 5 kilobytes of text can be downloaded in about a second.
Mbps (megabits per second): This is also a measure of data transfer speed. Mbps is used when comparing high-speed Internet connections. If you have a 1.5 Mbps downstream Internet connection (typical of cable modems and DSL) then you are capable of downloading 1.5 million bits per second.
Downstream: Transmission from a server to an end user. Downstream is usually measured in Kbps and Mbps.
Upstream: Transmission from an end user to a server. This is usually lower in speeds than downstream, and many people do not run servers for home use. This is also measured in Kbps and Mbps.
.03. TRIED AND TRUE: DIAL-UP SERVICE (Return to Index)
Dial-Up service is still one of the most common ways people connect to the Internet. For Dial-Up service, you need a modem. A modem is a piece of hardware that usually takes up a PCI slot (for PC users) and uses a telephone line to communicate with the Internet. Modems cost around $30 but come with most PCs.
Pros:
Who should use it: People who have no other choice, people who can't afford a faster connection method, or people who only want to do basic web browsing and email. Even people who do a lot of web browsing may want to check out something faster if available.
Average Cost:
Modem: $30
ISP: $20 a month.
.04. DIAL-UP'S DISTANT COUSIN: DSL (Return to Index)
DSL stands for Digital Subscriber Line and comes in two flavors. DSL is sometime referred to as xDSL, because there is ADSL and SDSL.
ADSL stands for Asymmetric Digital Subscriber Line. ADSL allows more data to be sent over copper phone lines at a much greater speed than Dial-Up offers. On average, ADSL supports downstream data rates from 1.5 to 9 Mbps and upstream data rates from 16 to 640 Kbps. ADSL is more popular in the United States.
SDSL stands for Symmetric Digital Subscriber line. SDSL allows for data transfer speeds of up to 3 Mbps. SDSL is called symmetric because the upstream and downstream speeds are the same. SDSL works by sending digital pulses in the high-frequency area of telephone wires. Because normal voice communications do not use SDSL, it can operate simultaneously with voice connections over the same wires. SDSL is more popular in Europe.
To connect to the Internet with xDSL, you need to purchase a special DSL modem that connects to your current phone line. This is usually purchased as part of the package you order when you get your xDSL Service.
Pros:
Cons:
Who should use it: Heavy web browsers, people who want to download large files and programs, online gamers, smaller server administrators (if upstream is high enough).
Costs:
Modem: $50-$75
Network Card: $30-$50
ISP: $50-$100 a month depending on package.
.05. DSL'S ENEMY: CABLE MODEM (Return to Index)
Cable modem service competes with DSL for the home broadband market. Instead of transmitting data over phone lines, data is sent over coaxial wire used by cable companies to send video signals. Coaxial cable provides greater bandwidth than standard telephone lines. Since millions are already wired for cable, it makes sense to be able to access the Internet over a pre existing infrastructure. However, cable television signals were only meant to be sent in one direction (from the "server" to the "client"). The Internet is a two-way system, but, because of recent technology advancements, upstream speeds have increased and are comparable to DSL speeds.
Cable Modem services usually get data transfer speeds of up to 2 Mbps downstream and up to 600 Mbps upstream on average. To connect to the Internet with a cable modem service, you need to have cable installed if not already. You also need to purchase a cable modem that runs about the same price as a DSL modem and usually comes with your package.
Pros:
Cons:
Who should use it: Heavy web browsers, people who want to download large files and programs, online gamers.
Costs:
$30-$75 for cable installation
$50-$75 for cable modem
$30-$50 for network card
$30-$80 a month for ISP
.06. ISDN: A SPECIAL KIND OF BROADBAND (Return to Index)
ISDN stands for Integrated Services Digital Network. ISDN comes in over phone lines, but requires that you dial into the network for access. ISDN is almost always guaranteed a certain speed, but the speeds are quite low considering the other options. Packages come in the form of 64 Kbps and 128 Kbps. This is shared so there is no upstream / downstream. Connections are made with an ISDN modem that usually comes with your package. Availability is also limited. ISDN also tends to be a bit pricier than other broadband options. As it stands, IDSN is mainly used for video conferencing lines.
Pros:
Cons:
Who should use: People who can't get DSL or Cable modem service, people who want to do frequent video conferencing.
.07. T-1, T-3, AND EVEN BIGGER (Return to Index)
T-1 lines are brought in over fiber optic line (or sometimes copper wire) that carries 24 digitized voice channels, or it can carry data at a rate of around 1.5 Mbps.
T-1s are generally used for businesses that want to run a server that will generate a lot of traffic, or companies that needs to split the bandwidth among its' employees. However, the costs are astronomical, and the availability is limited. Installation can run around $500, plus monthly fees of thousands of dollars. Usually, one person does not have a T-1 run into their home but some people do this.
T-3s are the next step up. T-3 is considered a backbone part of the Internet, and yes, connections can get even bigger. A T-3 can support 43 Mbps speeds and is composed of multiple T-1s. I have yet to hear of a single person or family with a T-3 in their home. T-3 connections are for large businesses, colleges and universities, and other large institutions.
T-1 and T-3 services also need lots of equipment to be useful. Routers, splitters, switches, are all hardware that is required to divide the bandwidth over its users. T-1 and T-3 lines are directly connected to the ISP so speed is almost guaranteed.
Pros:
Cons:
Who should use: Large institutions (schools, businesses, government buildings, etc), people who want to run heavy traffic servers.
Costs:
$500-$1000+ installation fees
$1000-$5000+ monthly fees
$500- $3000+ for additional hardware costs.
.08. CONCLUSION (Return to Index)
I hope this has helped you get a basic overview of how people get on the Internet. Of course, some of these numbers may already be out of date as far as transfer speeds go. The Internet grows at an incredible rate. Within 10 years, this document will probably be obsolete, as 10 years ago 56kbps modems were just becoming the norm. The services will still be the same, but as technology gets better and the thirst for bandwidth grows, we will see a great increase in speeds.