Web Site Administrator's Survival Guide - Chapter 2: Getting Connected | WebReference

Web Site Administrator's Survival Guide - Chapter 2: Getting Connected

Web Site Administrator's Survival Guide

Chapter 2: Getting Connected

Contents

Getting Connected

Connecting to the Internet can sometimes be a daunting task. With so many options to choose from, even the seasoned administrator can become discouraged. However, a little planning can make the task simple, if not enjoyable.

This chapter covers the following:

Sample Situations

This chapter and some of the following chapters use sample situations of web site construction for the clarification of many issues. Four fictitious customers are used to illustrate the discussion:

The large company has different needs than the small company, and each company has different needs than the Internet Service Provider. Hopefully, your situation fits into one of these categories, or at least somewhere between them.

The school example is Arkham University's paleontology department. Most of Arkham's departments are already connected to the Internet, but the paleontology department wants to put up a dinosaur-reference web site.

The large company is JazzAge, Ltd. JazzAge manufactures, produces, and distributes jazz compact discs and cassette tapes. JazzAge distributes its product to music and specialty stores around the United States. It has quite a large mail-order business as well. The company feels that offering its full catalog on the Internet will increase sales and draw in many new customers. JazzAge employs 600 people nationwide.

The small company is SquareNut, Inc., a fastener distributor. SquareNut buys fasteners of all types—bolts, nuts, screws, rivets, and so on—and then resells them to manufacturers of everyday household products. SquareNut wants to expand its customer base by adding the niche market of computer screws. The company's management feels that by maintaining an Internet presence, it can capture a market share in this area. SquareNut employs 40 people.

The last example is a start-up Internet Service Provider, Wild Onion Internet of Chicago, Illinois. It's a new business that wants to offer web services to customers and "rent" web space to local companies. Wild Onion employs three people, all of whom are programmers working in their spare time.

The end of this chapter summarizes by going over the choices made by each of the four example companies. This should give you a better understanding of the topics and what options exist for you.

Networking 101

Before you get your feet wet determining your connectivity needs and telecommunications requirements, a review of the terms and concepts to be discussed is in order. Some of you might already know what a DS-3 is, but there might be a few readers who think 9,600 bits per second is fast (hi, Mom!). Here's a brief networking/data communications overview.

Computer Communications

There are many different types of computer networks. The most common type of network is a Local Area Network, or LAN. A LAN connects a local set of computers so they can communicate with each other. A LAN can connect to other LANs. Other LANs that connect together in the same physical location only extend the LAN. If one of the other LANs that it connects to is remote, the entire network becomes a Wide Area Network, or WAN.

An analogy that comes to mind is space. Our swirling, spiral galaxy, the Milky Way, is part of what is known as a galaxy cluster. Countless galaxies make up this spiral mass. Observed from afar, a cluster looks just like a spiral galaxy. It's only when you look more closely that you discover the objects that make up the cluster are themselves other galaxies. A WAN exhibits the same principle: Only when you look closely do you realize that the nodes are other networks, not single computers.

For now, just focus on the communication between two computers. If you can nail down the concepts for this pathway, you can apply the same principles to communication between two networks. There really is no difference.

This pathway, as we've been calling it, is composed of two major components: a physical link and a transportation protocol. The physical link is the network cable or phone line that connects the two computers. The transportation protocol is the manner in which the computers talk. When humans talk, our voice is the physical link and the language we speak is the transportation protocol.

Modems

Instead of using sentences to communicate, computers use binary digits. There are only two binary digits: 1 and 0. To communicate these digits, computers use modem or direct connections. Digital signals cannot be sent directly over traditional, analog phone lines because they were designed with humans in mind, not computers. Computers require a device called a modem to translate from digital to analog and back.

Modem stands for modulator/demodulator. Because telephone lines transport data using analog signals, this device is necessary for a computer to decode the information it receives over the phone lines. The binary digits 0 and 1 are represented in analog as a low-frequency wave and a high-frequency wave, respectively.

A transmitting modem encodes the digital 1s and 0s into an analog signal by adjusting, or modulating, the frequency of the wave. The receiving modem decodes, or demodulates, the analog signal back into digital 1s and 0s.

Modems are classified by speed. The speed is measured in bits per second, or bps. A bit is one binary digit: a 0 or 1. In fact, bit is shorthand for binary digit. As the term bps implies, the bit transfer rate is the number of bits that can be transferred in one second. This rate, however, is the theoretical limit. Each packet of data carries some baggage with it, so actual transfer rates can vary.

Don't confuse baud rate with bit transfer rate (bps). They are not the same thing. The baud rate is a technical specification for modems. It defines the frequency at which electrical impulses are transferred to the communications medium. It only matches the bit transfer rate in some instances. Unfortunately, many people do confuse the two. Be aware that if someone states a speed in baud, they very well might mean bits per second.

Here is a list of the most common bit transfer rates for modems today:

You can probably pick up a 2,400bps modem pretty cheap these days, but you might not be able to connect to many services with it.

Check out these URLs for some great modem and telecommunications information:

https://www.modems.com
https://www.teleport.com/~curt/modems.html
https://molly.ipa.net/modem/
https://www.ee.umanitoba.ca/~blight/telecom.html

Other Communications Methods

In the past, asynchronous communication was adequate for the modem speeds of the day. But with today's high-speed modems and digital communications networks, transferring data bit-by-bit is slow and inefficient. Alternative protocols are available to add performance and efficiency. These protocols are packet-based, which means that instead of sending a bit of data, they send a packet of data. This packet varies in size depending on the protocol used. The protocol is made up of a combination of hardware and software. Each protocol works best in a certain range of line speeds.

In addition to the regular modems described previously, high-speed lines also are available. These lines all fall into a band category. These bands are

Numbers get confusing after a while, so large-capacity lines have names. Here are some of the more popular ones:

Here are a few other protocols that are now available:

Gauging Your Requirements

There are many types of Internet connections available from a wide variety of providers. The most common method of connection for new web sites is a dedicated feed, which consists of a leased line from your site to your Internet Service Provider. The line is conditioned, or cleaned, to provide the quality and clarity needed to run at higher speeds. Dedicated feeds can get quite costly because the phone company's charge is based on conditioning; for example, a line conditioned for 9600bps transmission is going to cost significantly less than a T1-quality line. In addition to the phone company's monthly charge, your provider owns half of the line. This cost is usually passed on to you in its monthly charge.

Dial-up connections, which provide you with "on-demand" access to the Internet, also are available. Your system can be configured to call your provider, transmit any queued data, receive any data bound for your site, and then hang up the line. This reduces your cost to the monthly fee and the cost of the phone call.

Both types of connections, dedicated and dial-up, require a hardware device to convert the signal received through the phone line into a recognizable network packet. The hardware required depends on the type of link you choose. Your Internet Service Provider can suggest the best hardware to use with its network.

Gauging your requirements is essential to deciding what level of connectivity you need. Your requirements can be broken down into two basic categories: presence and usage. Presence is the length of time (usually a percentage) you want to remain online and available. This will determine the type of connection you require. Usage is the quantity of data that you feel you need to send and receive. This quantity enables you to determine the line speed you need for the connection you choose.

Presence

Ultimately, there are just two choices for connecting to the Internet. If you require 100-percent presence, a dedicated feed of some sort is necessary. If you require less than 100-percent coverage, a dial-up link may be sufficient. However, because of usage requirements, at some point you will probably find a dedicated feed is more cost-effective than a dial-up.

If you require 100-percent presence but do not want to pay for a dedicated feed, there is one other option. Many companies sell web space on their servers. This service enables you to have 100-percent presence on the Internet but costs far less than a dedicated feed. The usual cost of this service can range from $5 to $1,000 per month depending on your needs. If this is the way you plan to go, you can probably skip the rest of this chapter and move on to Chapter 3.

Table 2.1 lists some sample prices for a dedicated feed from an Internet Service Provider. 

Speed

Price per Month

14.4Kbps

$125.00

28.8Kbps

$200.00

64Kbps ISDN

$250.00

128Kbps ISDN

$400.00

56Kbps

$450.00

T1

$1,750.00

Table 2.2 lists some sample dial-up feed prices. 

Speed

Price per Month

14.4Kbps

$20[nd]$50.

28.8Kbps

$30[nd]$75

One thing to note is that these prices do not include the cost of the line itself or any installation charges. In the case of ISDN lines, this can get quite expensive. In some areas, telephone companies charge by the minute for ISDN connectivity.

Usage

Usage of the link will be twofold: You have incoming traffic to your web server and outgoing traffic to other sites. Estimating your usage can be difficult. The best approach is a percentage of bandwidth method.

Bandwidth

Bandwidth is a measurement of the amount of data that can be transmitted or received through a connection. This is usually expressed in kilobits per second. Table 2.3 lists the most commonly used bandwidth options available from Internet Service Providers around the United States: 

Name

Bits/Second

Bytes/Second

9.6Kbps

9,600

1,067

14.4Kbps

14,400

1,600

19.2Kbps

19,200

2,134

28.8Kbps

28,800

3,200

38.4Kbps

38,400

4,267

56Kbps

57,344

7,168

64Kbps

65,535

8,192

128Kbps

131,072

16,384

T1 (1.5Mbps)

1,536,000

192,000

T3/DS3 (45Mbps)

46,080,000

5,760,000

All bandwidths are stated in theoretical limits. Overhead for link management, packet control, and other miscellaneous data is not included. For line speeds up to 38.4K, a 9-bit byte is used. Modems utilize an extra bit to signify the end of a character. Beyond 38.4K, 8-bit bytes are used because the data is usually transmitted in packets instead of characters. These packets are managed by the communications hardware.

Try to think of an Internet connection as a data pipeline. Depending on the size of the pipe, you can send and receive a small amount of data or a large amount of data at any given time. If you have more data than can fit in the pipe at one time, you have to wait until it empties out a little to send more data. The pipe fills up, however, with data going both ways. A small pipe would be a 14.4Kbps line. This has room for 14,400 bits (or 1,800 bytes) per second. A large pipe, such as a T1, has room for 1.5 megabits (or 192,000 bytes) per second. Figure 2.1 illustrates a typical Internet feed.


Figure 2.1. Your Internet connection.

There are larger and smaller bandwidth options—the 14.4K and T1 were chosen for clarity. As you can see, the T1 provides a huge amount of data. For instance, you could download a 4MB video clip in approximately 22 seconds over a T1, but it would take more than 30 minutes over a 14.4K connection.

Figure 2.2 illustrates the protocols available at different bandwidths.


Figure 2.2. Line capacities and available protocols.

Estimating Bandwidth

To accurately estimate the amount of bandwidth you require, you must measure the amount of data that you will send and receive. There is a catch, however. It is difficult to guess how much traffic your web server will receive initially. If you've got something new and unusual, you could get swamped. Some new web sites get "hit" up to 100,000 times per day! You'll just have to gauge the popularity of your web site beforehand to get an accurate number.

A request from a remote site to your web server is commonly called a hit. Later in the book, you'll see how to set up a hit counter for your pages.

First, if your web site is already designed, calculate your average page size. Most sites average about 35KB per page, including text and graphics. If you haven't designed your site yet, use the 35KB figure. If you plan on having lots of graphics and images, you might want to beef up that figure.

Second, estimate how many hits you think your server will receive per day. This is the tricky part. At first, your site might be hit quite often, but it will level out to a regular number. Expect a large wave in the beginning as word gets out that you are on the web. Now, multiply your hit-count estimate by the size of your average web page. For example, if you estimate your hit count to be 1,000 per day with an average web page size of 35KB, your daily server traffic will be roughly 36MB of data.

Finally, factor in space for other services you plan to offer, such as a news feed, e-mail, outbound Telnet, and inbound and outbound FTP. These are also hard to estimate, but are not immeasurable. If you plan to offer these services, you should reserve about 14.4Kbps of bandwidth just for them.

After calculating the bandwidth requirement for your Internet feed, take that figure and divide it by 28,800. This represents the division of the total data size over 8 hours into seconds (8x60x60). For this example, a bandwidth requirement of 36MB, we've come up with a bandwidth usage of 1,280 bytes per second. Add the 14.4Kbps reserved for other services and you have a total of 2,880 bytes per second. Looking back at the line speeds and bandwidth table, you can see that a 28.8K feed is sufficient to sustain this example's bandwidth.

Upward Mobility

As your Internet needs grow, your link will need to grow as well. Choosing some connectivity options can be costly if upgrading is in your future.

One of the newer connectivity options is fractional T1 service. This service uses a portion of the 24-channel T1 circuit, allowing 64Kbps increments from two-channel 128Kbps all the way to 1.5Mbps. This service varies in price from city to city. However, the average cost is significantly lower than a full T1. Some providers offer this type of flexibility with ISDN feeds as well. Fractional T3 services also are available.

If you plan on upgrading, steer clear of low-speed options such as 14.4Kbps and 28.8Kbps dedicated feeds. Most likely you'll be locked into hardware that's not upgradable and is unusable when you need more bandwidth. Don't buy a compact car when you're going to need a minivan. Go with an ISDN feed or a fractional T1. These links are scaleable and allow for future expansion.

Internet Service Providers

So far, you've determined the type and speed of service you require. Now it's time to shop for a provider. Selecting an Internet Service Provider, or ISP, can be difficult if there are many in your area.

Where to Look

Because you can't look in the phone book under Internet Service Providers, you'll probably need to use the Internet itself to locate ISPs. You might also find Internet Service Providers listed under the Computers section of the Yellow Pages. But if you want to find a hen, look in the henhouse. Check out the web sites of each potential ISP. Mentally rate each provider's site—this will be reflective of its service.

Most large long-distance companies now offer Internet services. Sprint, MCI, and AT&T have offerings that compete with local providers. If you are going to have a large-capacity line (T1 or greater), you might be better off going with a major player. These larger companies might be able to provide less-expensive solutions and have years of communications experience.

For comprehensive lists of Internet Service Providers, check out the following URLs:

https://thelist.internet.com

https://www.cybertoday.com/cybertoday/isps/

https://wings.buffalo.edu/world

What to Ask

When choosing a provider, you must decide which features and services are most important to you. Following are some areas about which you should question your ISP:

What is a POP?

A POP, or Point of Presence, is a location for connecting to an ISP. Depending on the size and customer base of the ISP, it might have POPs located throughout an entire area, or just one POP. Each ISP is different. Figure 2.3 shows some example POP locations in Illinois for several ISPs.

If you are going to connect to your ISP with a dial-up link, the locations of your ISP's POPs are very significant. Some local phone companies bill phone calls based on the distance between the two calls. If you are calling a POP that is 30 miles away, it will cost you more than calling a POP that is 5 miles away. Check with your phone service provider to ensure the charges are acceptable.


Figure 2.3. Example POP locations in Illinois.

Following is a list of services you should look for in an ISP. Pick the ones most important to you and ensure that the ISP you choose has them.

In most situations, ISPs resell portions of the bandwidth that they have purchased. You'll find that the total bandwidth sold is far beyond their total bandwidth. If your ISP is selling you a T1 link, ensure that you are buying a T1 link to the Internet, not to the ISP.

Connecting the Dots

Now that you've learned about all of the available options and how to select a service level, now it's time to check with the example customers and see how and what they chose.

Arkham's paleontology department already has connectivity to the Internet from the computer science department of the school, and has totally skipped this chapter.

JazzAge has estimated that its web site will be heavily used and is thinking toward the future. The company has determined that it requires 100-percent presence with moderate inbound usage, and therefore chose a 64Kbps ISDN feed that is upgradable to a 128Kbps feed. JazzAge also will use the Internet for market research and will run contests with giveaways to attract business.

The third company, SquareNut, wants to maintain a 100-percent Internet presence but does not want to pay for a dedicated feed. Most of its employees don't use computers in the office, so the Internet is not a tool they would readily use. SquareNut has decided to rent web space on its local ISP's server. This provides the company with an adequate amount of disk space and its own domain name, e-mail, and other value-added services. The company will hire a consultant to maintain its web pages.

The last example company is the Internet Service Provider, Wild Onion Internet. The company wants a big pipe so its customers will get the best feed in town. It has contracted to get a T3 from Sprint.

Summary

This chapter describes how to estimate your Internet usage, determine your presence, and make an educated decision regarding the level of connectivity you need. You have also learned a little bit about bandwidth and how it's measured.

Buzzword Checklist

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