Internet Telephony for Dummies (with CD-ROM)

( 1 )

Overview

Free voice and digital video conferencing over the Internet -- too good to be true? Internet Telephony For Dummies, 2nd Edition, shows you just how true -- and easy -- it is to communicate by voice and video with most any Internet user anywhere in the world.

In Internet Telephony For Dummies, 2nd Edition, authors and telecommunications experts Daniel D. Briere, Patrick J. ...

See more details below
Available through our Marketplace sellers.
Other sellers (Paperback)
  • All (7) from $4.84   
  • New (2) from $97.18   
  • Used (5) from $4.84   
Close
Sort by
Page 1 of 1
Showing All
Note: Marketplace items are not eligible for any BN.com coupons and promotions
$97.18
Seller since 2008

Feedback rating:

(203)

Condition:

New — never opened or used in original packaging.

Like New — packaging may have been opened. A "Like New" item is suitable to give as a gift.

Very Good — may have minor signs of wear on packaging but item works perfectly and has no damage.

Good — item is in good condition but packaging may have signs of shelf wear/aging or torn packaging. All specific defects should be noted in the Comments section associated with each item.

Acceptable — item is in working order but may show signs of wear such as scratches or torn packaging. All specific defects should be noted in the Comments section associated with each item.

Used — An item that has been opened and may show signs of wear. All specific defects should be noted in the Comments section associated with each item.

Refurbished — A used item that has been renewed or updated and verified to be in proper working condition. Not necessarily completed by the original manufacturer.

New

Ships from: Chicago, IL

Usually ships in 1-2 business days

  • Standard, 48 States
  • Standard (AK, HI)
$215.00
Seller since 2015

Feedback rating:

(215)

Condition: New
Brand new.

Ships from: acton, MA

Usually ships in 1-2 business days

  • Standard, 48 States
  • Standard (AK, HI)
Page 1 of 1
Showing All
Close
Sort by
Sending request ...

Overview

Free voice and digital video conferencing over the Internet -- too good to be true? Internet Telephony For Dummies, 2nd Edition, shows you just how true -- and easy -- it is to communicate by voice and video with most any Internet user anywhere in the world.

In Internet Telephony For Dummies, 2nd Edition, authors and telecommunications experts Daniel D. Briere, Patrick J. Hurley, and Rebecca Wetzel reveal

  • What the Internet is and how Internet telephony fits in
  • What hardware and software you need -- and where to get them
  • How to make a call from your PC to a regular telephone
  • How to set up videoconferencing
  • How to get the best possible sound and image quality for your connection speed

Plus, Internet Telephony For Dummies, 2nd Edition, comes complete with a bonus CD-ROM containing Mac and Windows software such as AT&T WorldNetSM Service for Internet access, Internet Explorer 3.02 Web browsing software, and CU-SeeMe, Internet Phone, and WebPhone so that you can try out voice and video Internet telephony right away.

Read More Show Less

Product Details

  • ISBN-13: 9780764501746
  • Publisher: Wiley, John & Sons, Incorporated
  • Publication date: 7/28/1997
  • Series: For Dummies Series
  • Edition number: 2
  • Pages: 384
  • Product dimensions: 7.41 (w) x 9.28 (h) x 1.03 (d)

Table of Contents

Introduction
About This Book
Where to Go from Here?
Part I: Internet Telephony and Video, Unplugged
Part II: You Make the Call: Using Internet Telephony Products
Part III: Internet Telephony: Not Just for PCs Anymore
Part IV: The Part of Tens: Hip Stuff from the Internet
Part V: Appendixes
Icons Used in This Book
Conventions Used in This Book
Feedback, Please
Part I: Internet Telephony and Video, Unplugged

Chapter 1: What's Internet Telephony and Video?

Sending Your Voice and Video over the Internet
Who can use it?
Just whom may I call?
Where Is It All Going?
Why Do It over the Internet?

Chapter 2: Internet Telephony 101

How the Heck Do I Communicate over the 'Net?
Transmission control protocol (TCP)
User datagram protocol (UDP)
A new addition: Real-Time Transport Protocol (RTP)
Moving your data from here to there
Understanding general Internet issues
How Does an Internet Phone Call Work?
Connecting across the Internet
Combining the best connection features: Directory services
Getting a Handle on Internet Conferencing Standards
Why worry about standards?
And the standards are . . .
Gateways to the World
Extra Credit: Fax over the 'Net

Chapter 3: Getting Yourself on the Internet

Getting onto the Internet
Figuring out who the providers are
Getting ISP support for telephony and video
Picking an ISP
Choices, choices, choices
Gauging Your Telephone Line Requirements
Being analog
Deciding on digital (I want my ISDN now)
Getting and paying for digital service
Getting a direct connection

Chapter 4: Getting Outfitted for Internet Telephony

Setting Your Standards
When in Doubt, Go with the Best
The golden digital signal processing (DSP) rule
TCP/IP network and node address
10MB hard disk space
Connectivity hardware
Microphones and Speaker Options
Here's talking to you, kid
What did you say?

Chapter 5: Getting Outfitted for Internet Video and Multimedia

Getting Video on Your System
Here's Looking At You, Kid
Digital video output computer cameras -- the Connectix QuickCam and Color QuickCam
Analog video output computer cameras
Camcorders and general-purpose video cameras
Video capture cards
Taking a Look at Video Standards
True Motion video standards
Videoconferencing standards
QuickTime and Video for Windows

Chapter 6: Getting Your PC Set Up for Internet Telephony

PC Minimum System Requirements
PC Recommended System Requirements
More on What You Need to Make Your System Work
486 or Pentium processor
8MB RAM
Windows 3.1 or later
TCP/IP -- Winsock 1.1 or better compliant
Sound cards
VGA card of 256 colors
Older PCs
An Introduction to PC Internet Telephony Programs -- WOW!
Microsoft NetMeeting
Netscape Conference
Intel Internet Video Phone
VocalTec Internet Phone
CU-SeeMe
WebPhone
FreeTel
Voxware TeleVox
DigiPhone
Speak Freely
Other PC programs
Installing Internet Phone on your PC
Installing Other Programs Is Just As Easy

Chapter 7: Getting Your Mac OS Computer Set Up for Internet Telephony

Mac Minimum System Requirements
Mac Recommended System Requirements
More On What You Need to Make Your System Work
68030, 040, PowerPC
8MB RAM
System 7.0 or greater
SoundManager 3.x
TCP/IP-Open Transport or MacTCP installed -- Open Transport 1.1.2 preferred
Sound cards not needed
Mac Internet Telephony Programs
Netscape Conference
CU-SeeMe
Internet Phone for Macintosh
PGPfone: say what you please
An old favorite with a new name: DigiPhone for the Mac
Other products for the Mac
Installing Internet Phone on Your Mac: Easy as (Apple) Pie

Chapter 8: The "Now Ready for Real-Time" Audio and Video Players

How Live Audio and Video Products Work
Is it live, or is it on demand?
Hardware? Chances are, you've got it
What Are Your Options?
Low, low price
Plug-in versus helper
Multicasting -- the future of streaming?
Streaming Video Applications
Progressive Networks' RealPlayer
Microsoft NetShow
Vivo Software's VivoActive
Xing StreamWorks
VDOLive
Audio-Only Apps
DSP Group True Speech
Macromedia Shockwave
Netscape Media Player
VocalTec IWave
VoxWare ToolVox for the Web
Where to Start?
Part II: You Make the Call: Using Internet Telephony Products

Chapter 9: Using Microsoft NetMeeting

What Does NetMeeting Look Like?
Getting Yourself Configured
How Do I Make a Call?
Placing a call by using the ILS Directory
Calling directly
Speed dialing
Incoming!
Making adjustments
Breaking up is hard to do (Hanging up isn't)
What Else Can I Do with NetMeeting?
Application sharing
File transfer
Whiteboarding
Text chat
It's a Party: Multiparty Conferences
What you can and can't do in a meeting
Hierarchies, and stuff like that
How to set up a meeting
Putting NetMeeting to Bed

Chapter 10: Using the VocalTec Internet Phone

A Quick Peek at the Interface
Configuring Internet Phone
Fine-tuning your audio
Setting up your video
Making the Server Serve You
Connecting to the server
Getting into Chat Rooms
Initiating the Call
Messing around with video
Putting someone on hold
Hanging up
Finding out who's online
Saving Names and Making Calls
Using your Personal Directory
Tracking down someone you already talked to
Using the Session List
Making a Direct Call
Receiving a Call
Manual Accept
Automatic Answer
Blocking calls
What if you're already talking to someone else?
Other Neat Features
Using the Text Chat feature
Using the Whiteboard
Sending a voice mail message
Transferring files
Say Goodnight, Gracie: Quitting Internet Phone
Internet Phone for the Macintosh
Calling from the OnLine Directory
The virtues of being direct
Using the QuickDial feature
Getting back to work

Chapter 11: Using Intel Internet Video Phone on Your PC

A Quick Look around Internet Video Phone
Configuring Internet Video Phone
Establishing calling preferences
Getting listed
Setting your general preferences
Making Your First Call
Calling from a Web directory
Video fun
Placing a direct call
Remember to say "Hello"
Star 69 (Not the REM song)
Speed dialing your way to happiness
Ciao!

Chapter 12: Using Netscape Conference

Snooping Around
Setting Up Conference on Your PC
Off to see the wizard
Options, options, options
Conferencing Know-How
Calling using the DLS system
Adjusting your call quality
Reach out and touch someone on the Web
Adding someone to your Conference Address Book
Calling from the Address Book
Using Speed Dial
Receiving a call
Sharing Is Caring
Better than a chalkboard, but no erasers to clap
Using Text Chat
Browsing the Web with someone else
Sharing files
Talking to the answering machine
See Ya!

Chapter 13: Picture This: Using CU-SeeMe 3.0

The CU-SeeMe Interface
I've Got a Configuration, Jones
Setting things up
Editing your personal profile
Setting calling options
Testing it out
Videoconferencing for (And with) Everyone
Making a call from the PhoneBook
Looking, talking, making adjustments
Hanging up
Be direct!
Checking out who's online
Keeping Track of Addresses
CU-SeeMe and the Web
The WhitePineBoard
Part III: Internet Telephony: Not Just for PCs Anymore

Chapter 14: PC-to-Telephone Gateway Services

What's It All About?
What Do You Need to Use Gateways?
Who Offers Gateway Services?
IDT's Net2Phone
Global Exchange Carrier (GXC)
Killer Applications: Commerce and Call Centers

Chapter 15: Telephone-to-Telephone Gateway Services

What's the Deal?
What Kinds of Services Will Be Available?
Who Offers (Or Has Announced) These Services?
What's Holding Back Development?
The Real Goal: Convergence

Chapter 16: Using Internet Telephony in Your Corporate Intranet

Why Use Internet Telephony on Your Intranet?
The bottom line is the bottom line
Productivity ain't too shabby, either
Internet telephony just plain works better on an intranet
An Easy First Step: Using Client Software
More Complicated, But More Sophisticated: Using Gateways

Chapter 17: Using the Internet for Faxing

Why Does It Make Sense to Fax on the 'Net?
How Does Internet Faxing Work?
How to Get Started with Internet Fax
Some Service Providers
FaxSav
NetCentric FaxStorm
Future providers
Part IV: The Part of Tens: Hip Stuff from the Internet

Chapter 18: Ten Ways You Can Use Internet Telephony and Video Now

Chapter 19: Ten Hot 'Net Sites Where Video Is Used Today

Chapter 20: Ten (Plus One) Tricks to Sounding and Looking Good on the 'Net

Chapter 21: Ten (Or So) Good FAQs and Mailing Lists to Check Out

Chapter 22: Ten Good Publications to Read to Follow This Topic

Chapter 23: Help File: Ten Common Problems and How to Fix Them

Chapter 24: Ten Neat Things You Can't Do on the Net -- Yet!

Chapter 25: Ten Things About to Happen with Internet Telephony and Video

Part V: Appendixes


Appendix A: U.S. National Internet Service Providers

Appendix B: Gateway Hardware Vendors

Appendix C: About the CD

Index

License Agreement

Installation Instructions

IDG Books Worldwide Registration Card

Read More Show Less

First Chapter

Chapter 2
Internet Telephony 101

(The online version of this chapter has been abridged.)

In This Chapter

  • Avoiding bandwidth bottlenecks
  • Understanding the limitations of Internet telephony
  • Getting on the Internet
  • Getting up to speed

Internet is short for internetwork, a term that means connecting different networks together so that they can function, everyone hopes, as one. Indeed, that's what the Internet really is -- a massive network of networks that looks like a single system to you, the user.

In this book, we don't feel the urge to put forth the obligatory Internet history lesson (ARPANET, CERN, and all that stuff), because the chances are good that you've heard that about a MILLION times already -- and if you haven't, you really don't need to know what happened 15 years ago to take advantage of Internet telephony and video applications today.

If you want to know where the Internet came from, how it evolved, and how to master it, check out some of the other ...For Dummies® books, such as The Internet For Dummies®, 4th Edition, by John Levine, Carol Baroudi, and Margaret Levine Young; or The Internet For Macs® For Dummies®, 2nd Edition, by Charles Seiter.

For the purposes of this book, the Internet is a network of networks that enables end users to transmit and receive audio and video communications across a variety of interconnections. Your connection into the Internet enables you to exchange telephony and video communications with others who have similar connections (see Figure 2-1).

How the Heck Do I Communicate over the 'Net?

When we talk about communicating over the Internet, we don't mean just talking or viewing video. Everything about the Internet has to do with communications, whether you're sending e-mail, sharing a file or data, or making a phone call. To the Internet, all these activities are really about the same thing -- transporting bits. The Internet doesn't know whether the packets (small chunks of data) it transports contain your voice or someone's doctoral dissertation on fruit flies with big ears. Nor does the Internet care, generally speaking.

The Internet uses standard protocols to control the flow of data from one point to another. The main protocol, on which everything is based, is Internet Protocol, known as IP. (Make sure that you always remember your IP address -- and remember, too, that every computer on the Internet has its own unique address that identifies that machine -- and only that machine.) The switches, or routers, direct traffic across the 'Net and rely on the Internet Protocol to tell them where packets of data are going. Internet Protocol is really the low-level common denominator of the Internet.

Transport protocols monitor and control data transmission. The two important transport protocols are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). Internet telephony and video programs use one or the other of these protocols, and knowing more about them is important when you're ready to select your telephony software and an Internet Service Provider (ISP).

Transmission control protocol (TCP)

Don't worry too much about remembering the full name of this protocol; you won't be quizzed. The main thing to remember about TCP is that it's a more reliable protocol than UDP (which we describe in the following section). Data transferred by TCP is checked at the far end to ensure that all packets are received -- and if some are missing or lost, TCP resends them. This protocol is great for transferring a data file or an application that doesn't work if even a small piece of data is missing. However, TCP is not so great for transmitting a phone call, because you must wait for TCP to confirm a packet's arrival and then resend the data if it doesn't show up.

User datagram protocol (UDP)

Data sent under UDP is not checked at the receiving end to ensure that all the packets have arrived, and no method exists for resending the data if some is lost along the way. Thus UDP translates into faster transfers at the expense of possibly losing some of the data. Internet telephony and video program designers usually use this system because they've decided that the increased speed and decreased delay outweigh the potential downside of losing a few data packets. You may want to check out the sidebar "Watch out for firewalls" in Chapter 3 for information about UDP and firewalls.

If you have a choice, UDP is the preferred protocol for Internet telephony and video programs.

A new addition: Real-Time Transport Protocol (RTP)

As we mention in the preceding section, developers of Internet telephony and video programs have traditionally used the UDP as the means for sending your voice and video across the 'Net. They've also realized that UDP wasn't really designed for real-time communications -- it's just better than the TCP alternative. So to make things work a bit better, they've designed a new protocol -- actually a pair of protocols: Real-Time Transport Protocol (RTP) and Real-Time Transport Control Protocol (RTCP).

Yet another protocol

We don't want to load you up with too much information on protocols and standards and all that underlying techie stuff that makes 'Net telephony work. After all, if you end up scratching your head and staring glassy-eyed at the book, you'll never get to the fun stuff (actually using the programs). However, we do need to mention one last protocol that is closely related to RTP. Real-Time Streaming Protocol, or RTSP, is a variant of RTP designed specifically for one-way "streaming" multimedia programs -- the Internet TV and radio programs that we talk about in more detail in Chapter 8.

RTSP was developed by Netscape and some of its technology partners as a way to improve the quality of these streaming products and is now a standard. Like RTP, RTSP adds some information to the packets of audio and video data sent over the 'Net that makes it easier for programs to reproduce the multimedia when it gets to your computer.

RTP and RTCP (which work together, and are usually referred to as just RTP) help make your Internet calls work better by adding some special information to the packets you send across the 'Net. Most importantly, RTP adds special timing information to the packets to help programs get these chunks of your call data back together in order on the other end.

Basically, a real-time communication over the Internet is one in which the data (your voice or video) is played back on the other end of the connection immediately as you send it. In the real world, communications over the Internet (or any network for that matter) are never perfectly real-time, due to latency. Latency is the delay imposed upon the signal by the components of the network (it takes a bit of time for all of those routers to figure out where to send the data) and by physics (your data can only go as fast as the speed of light -- which is pretty darn fast but adds a small element of delay when you're talking to someone really far away).

Note: RTP isn't actually a replacement for one of the basic Internet protocols (namely TCP or UDP). In fact, most programs that use RTP use it in addition to UDP (that is, your RTP call is sent over a UDP "connection") -- so even if you communicate with a program that uses RTP, you probably also use UDP as your underlying protocol, with the same benefits and drawbacks.

Moving your data from here to there

The actual transmission of a packet across the Internet is akin to passing a baton in a relay race. A packet is sent from one switch to another. Each switch examines the packet and sends the packet where that switch thinks best. With an international transmission, having a data packet pass through tens of switches is not at all unusual.

Did you RSVP?

In the near future, you may be able to forget everything that you know about how communications on the 'Net work. That's because some major equipment vendors (Intel and Cisco Systems) and an important Internet Service Provider (BBN Planet -- one of the original builders of the Internet) have just announced that they are supporting a new Internet protocol called RSVP, or Resource Reservation Protocol, which has been proposed by the Internet Engineering Task Force (one of the groups that controls how things work on the 'Net).

The RSVP protocol is a standard that enables applications, such as videoconferencing, to communicate with the network equipment in their call path and ensure that enough bandwidth is available for the duration of the session (128 Kbps in the case of the applications we are discussing here). If that level of bandwidth is available, it is reserved for the application; if not, the call isn't connected, sort of like a network busy signal.

This reservation process helps ensure that the delays, lost packets, and outright disconnects that sometimes occur today become a thing of the past. We can't wait!

The Internet uses something called dynamic routing to move data from one place to another. In dynamic routing, the routers that switch packets of data between points on the 'Net try to determine the best route for each individual packet as that packet comes through. The chosen route may not always be the most physically direct route. If, for example, the shortest route is tied up with traffic or has a system failure or is in the path of a major natural disaster, the Internet finds another path and sends the data across it.

Understanding general Internet issues

Being a massive network of networks, the Internet has its own set of hardware, software, protocols, procedures, and overall capabilities. Among the issues that affect how Internet telephony and video signals are carried across the network are the following:

  • Bandwidth
  • Packetization
  • Prioritization
  • Quality assurance
  • Security
  • Cost
  • Freedom of speech

Bandwidth and compression

If you want to pump water from one place to another, how quickly you can do so depends on the size of the pipe and the speed of your pump. The Internet works the same way -- the pipes are the telecommunications circuits that comprise the various networks that form the Internet.

Bandwidth refers to the amount of data a given connection (such as a modem connection) can pass in a given amount of time. Bandwidth is typically given as the number of data bits that can be sent per second, such as 28,800 bits per second. (A bit is the smallest unit of data that computers handle -- you can think of it as the computer equivalent of an atom.) The more information contained in a signal, the bigger the pipe -- that is, the more bandwidth -- that's required to send the signal through in the same amount of time. The more bits per second you can fit in that pipe, the more you can send across the wire. Conversely, the more information a signal contains, the bigger the pipe required to send all of the signal in the same amount of time. As shown in Figure 2-2, the amount of bandwidth required for most audio and video signals is greater than the size of your pipe.

Bandwidth can obviously limit the quality of Internet telephony and video because these communications applications are time dependent. That is, things must happen within a certain time frame to make the communications usable. A minimum interval separates the bits moving over the 'Net.

Most people have a pipe of limited size, however, so the answer is to use compression to reduce the size of the digital signal heading through the modem or other connection point. Compression is a way of taking certain information -- for example, repeated or nonessential data -- out of a data stream. See the sidebar "Compression schemes (and data streams)" for more information.

The trick is to move things fast enough to meet the minimum time intervals required without sacrificing the overall data message. You must compromise somewhere, and this compromise usually rears its head in the form of sampling and compression, as defined in the following list:

  • Sampling: How often you measure the analog voice signals to digitally store a copy of the signals for transmission.

    As an example of sampling, think of the way a movie looks on your TV when played from a VCR tape. Now think of how the same movie looked at the theater. The VCR version should seem a little less crisp in your mind and maybe not as colorful. This is because, to fit that entire movie onto a video tape, some shortcuts must be taken. The movie is sampled into a smaller version of itself. In most cases, however, the movie comes across just as good to the viewer as the original. Internet telephony and video work the same way to get through the bottlenecks in the network fast enough to maintain the quality of the conversation's timing.

  • Compression: A compressed signal, using much less bandwidth, is also more Internet-friendly and less likely to clog up what is already a busy network. See the sidebar "Compression schemes (and data streams)" for more information.
Two potential bandwidth (pipe) bottlenecks can affect you:
  • In the local connection, at either end of the connection: This connection is usually the local telephone line to which you attach some sort of modem or other transmission device.
  • On the backbone of the Internet itself: Data flow across the Internet and through the various network interconnection interfaces can be impeded by traffic congestion, limited circuit size, and limited hardware connections, among other things.
You have control over your local connection. Choosing a faster connection method -- such as a faster modem or maybe an integrated services digital network (ISDN) line -- can help alleviate bandwidth limitations in your local connection, as can choosing a good Internet Service Provider (ISP) who is outfitted for this sort of Internet traffic. We help you understand how to do both items in Chapter 3.

The Internet network bandwidth limitations are, of course, out of your control but can affect the quality of your calls. You no doubt are going to notice that Web surfing during the middle of the business day, when 'Net usage is heavy, may not be as quick as it is later in the evening. That's because everyone else is trying to surf at those high peak times. Because Internet telephony and video signals are just like those of any other data flowing over the Internet, they are subject to the same congestion and quality effects at high-usage times.

Compression schemes (and data streams)

A decent compression algorithm makes or breaks an Internet telephony or video product. Many different compression schemes are available. Some, such as the GSM (Global System for Mobile Communications) algorithm used in mobile phones, are free for all to use, while others are proprietary. (Many Internet phone programs use a proprietary algorithm and are likely to advertise it as "the best.")

All compression schemes, however, fall into one of two main categories: lossless and lossy:

  • Lossless compression generally finds repeated parts of the signal, removes them, and then puts them back in at the other end. The result is a signal that ends up being identical to what went into the front end of the system. This feature is very important in data applications, as in transferring Excel files, but less so for voice.
  • Lossy compression methods, in comparison, use advanced modeling techniques to determine what is really important to the signal being understood and what can be left out. The signal received on the far end of this system is not the same as what went in, but if the programmers and scientists did their job, the signal should sound or look pretty much the same at both ends. These lossy compression methods, because they can remove more data, are typically more efficient (that is, they compress the signal to a greater degree) and are used for all the audio and video applications that we discuss in this book. <\UL> Some compression programs reach a 50:1 compression ratio, which means that if you have a 50MB file going in, you have a 1MB file coming out. That's pretty impressive compression.

Of course, if a Web site takes an extra 20 seconds to load, you are perturbed but not put out. With time-sensitive telephony applications, however, you can be stopped in your tracks.

Note: We're of the "if they come, someone will build it" school of thought concerning growth of Internet capacity. The almost overwhelming commercial and public demand to be online is sure to drive those groups who collectively continue to build the Internet to expand the backbone bandwidth to accommodate increasing Internet demands.

Packetization

If you look at what is happening as information streams off your computer, over the local access line, through your Internet Service Provider's switch, and into the Internet, you see that the data stream goes through some big changes. Your computer breaks down the data it sends over the Internet into smaller pieces of data known as packets. Each packet has a header that identifies it and its destination. Switches on the 'Net, known as routers, read this header, determine where the packet is going, and send it farther along on its way.

What's an Internet Service Provider?

An Internet Service Provider, or ISP, is just what the name says it is: an organization that provides Internet service or access. ISPs range from small local companies with one access number and 20 or so modems up to huge multinational corporations that provide service to subscribers all around the world.

An ISP doesn't need to be a company either. If you are connected to the Internet through a college, for example, the school is your ISP. (Although it may, in fact, be leasing its 'Net access from one of the large ISPs.)

Basically, you can think of an ISP as your on- and off-ramp to the Internet.

We talk about things to look for when choosing an ISP, and how that choice can affect your use of Internet telephony and video products, in Chapter 3.

After the packets arrive at their destination, the receiving computer reads the headers of the individual packets, puts them back in order if need be, and directs them to whatever program on your computer needs them.

Each packet could take a totally different route through the Internet to get from point A to point B. Data is sent out, bounces from place to place in a somewhat organized fashion, and eventually arrives at its destination. You have no guarantee, nor do you need one, that your next chunk of data is going to follow the same route as the previous one. This type of routing is called connectionless routing, because it does not depend on a specific path for the transmission.

The effect of packetization and connectionless routing is one of timing. Because successive packets in a transmission can travel different routes between two points on the Internet, they can arrive at their destination at different times. Some packets in a transmission may take a long time to arrive at their destination. The computer at the terminating end may wait and store the packets in a buffer so as to put them in correct order without dropping any packets. Some computer applications proceed without the delayed packets and send the data to the screen or output device with holes in the data stream. You may not notice these holes, because the amount of data in each packet is so small that one dropped packet is no big deal -- the holes may result only in a small clipping of speech or a few portions of the screen freezing for a subsecond.

The packet arrival rate is not necessarily always staggered, however. At times when the network is underutilized, packets can arrive in their correct order and in perfect synchronization.

We call the environment in which packets may or may not arrive on time and in sequence variable real-time communications.

Prioritization

Prioritization -- or lack thereof -- is another facet of the Internet that may affect your use of Internet telephony and video programs.

Consider what happens if you make a phone or videoconference call today over the regular telephone network (which is called the Public Switched Telephone Network, or PSTN). Like the Internet, the PSTN is a network of networks, made up of interconnections between the long-distance carriers, local telephone companies, cellular companies, and others. The PSTN, however, is designed to offer a higher level of quality at a correspondingly higher price.

Say that you place a telephone call from your home in Peoria to your brother's house in Missoula using your carrier, MCI. After your brother answers the phone, you have a connection that is exclusively yours, running through the telephone network. You can engage in a reliable, fixed-bandwidth, stable conversation over the network, regardless of how many other people choose to place calls in the midst of your conversation.

Purists may point out situations in which this scenario is not wholly true, such as with international links, where bandwidth is constrained; in these cases, bandwidth can be scaled back as more people come onto the connection, depending on the telephone carrier.

With the Internet, the picture is slightly different. You do not have an end-to-end connection reserved for you during your communications, nor a guaranteed level of bandwidth; instead, your data travels over a shared backbone that can cause you problems during periods of high Internet usage. Internet telephony does not offer a way to achieve a higher level of quality or to obtain any sense of prioritization over other people's traffic. But the Internet is a low-cost, viable option whenever you are willing to accept its terms and limitations.

The simple solution is to call over the PSTN if your business is of a critical nature. With the PSTN, you essentially reserve your bandwidth any time you make a phone call.

Quality assurance

A related, yet slightly different, angle on the Internet is quality control. Because the Internet is made up of hundreds of networks and providers, you have no promise of consistency.

Consider again your call from Peoria to Missoula, except now you get cut off before you finish. If you're using a traditional local or long-distance carrier, you can contact the carriers, complain, and probably get your money back. MCI, for its part, can pull up call records and attempt to determine what went wrong. It can talk to the local carriers who were part of the call and reconstruct an exact circuit-by-circuit map of how that call was placed, and each carrier can test that circuit for problems. You can be fairly well assured that all participants are going to try to fix the problem so that it doesn't happen again. That's part of what you are paying for.

Calls made over the Internet have no such assurances of quality or reliability. Your provider of Internet access services can only assure you a quality connection into the Internet; after your data crosses out of your ISP's equipment, your data packets are on their own. (We hope you have tough data packets -- it's a rough world out there.)

In the not-so-distant future, you can expect to see companies offering some sort of industrial-strength Internet service that parallels the Internet but has more of the quality and reliability controls of the PSTN. You're probably going to have to pay more for it, too.

Telephone and videoconferencing are both very forgiving applications; if you lose a small piece of your data stream, you may merely clip a word or not refresh a portion of the video picture for a moment -- not nearly as devastating as losing part of a spreadsheet or word processing file.

Privacy

Is someone listening? Probably not, but possibly. We're not paranoid, but the fact is that any data you send over the Internet travels an unpredictable and convoluted path through many switches before it reaches its final destination. On a theoretical level, somewhere along the way, in any of these switches, people can, if they really want to, intercept some of your data and read, listen to, or watch it.

Should you worry? Not really. We argue that privacy is very much a nonissue. In practice, all that anyone may obtain is snippets of information that don't make much sense without the bigger picture (pardon the pun).

Some Internet telephony products have options, such as encryption, to protect your privacy. See the discussion of PGPfone in Chapter 7 for more on this topic.

Cost: How long will it be free?

Strictly speaking, the Internet is not free. Someone has to pay for all those miles of fiber optic cable and wire and the servers and routers that make up the 'Net. At first, the government paid (sorry, a little history slipped in), but now the Internet is privately maintained and built. Your Internet Service Provider pays for its little part of it, and you, of course, pay the ISP.

But unlike the PSTN, the charge is not based upon the distance you send your data or what time of day you send it. In fact, with the advent of unlimited Internet access service pricing, you don't even pay for how long you use it or, up to a limit, how much data you send.

Some local telephone company access-line options, as we describe in Chapter 3, do carry per minute or per hour fees, however, so you could be hit with some add-on fees.

Overall, although the Internet is not really free, it sure is cheap. Now, how long can this low-cost status continue? No one really knows for sure. Many pundits, including us, believe that alternative Internets may offer similar connectivity options, with higher quality, reliability, customer services, and so on -- for a slightly higher subscription fee.

Free(?) speech

Freedom of speech is surely a slippery issue when you think of the Internet these days. As we write, the Internet is on trial (to quote the headlines). Certain groups (some of whom know about the 'Net, some of whom really don't quite get it) want to regulate the Internet as they would a broadcast medium (television or radio, for example). Others see these rules as the first step on a slippery slope that infringes on the free speech of all 'Net users. So a battle rages.

We don't want to have to choose sides here, but we can say this: Regulating the 'Net is impractical at best and perhaps even impossible. You can log on from your computer in Arizona and, within a minute, be reading files from a computer in London or talking to someone in Kuala Lumpur, Malaysia. Laws that apply in Singapore, for example, don't apply in the United States or France. The global nature of the 'Net makes it almost immune to efforts of a single country to control it.

Freedom of speech is likely to become a big issue with Internet video especially, because a whole industry is ready to offer nude shows via the Internet for anyone with a credit card in hand.

Although a regulator may be able to control static text or graphics files at a Web site, dealing with real-time voice and video communications is a different story. No record is left behind, so unless the regulator can monitor everything as it happens, enforcement is impossible.

Note: Consider that you can pretty much say anything, about any subject, on the phone with impunity. If you use the phone to harass someone or to plan something illegal, you may be breaking the law -- but no one tries to censor the phone system itself.

(The online version of this chapter has been abridged.)

Read More Show Less

Customer Reviews

Average Rating 5
( 1 )
Rating Distribution

5 Star

(1)

4 Star

(0)

3 Star

(0)

2 Star

(0)

1 Star

(0)

Your Rating:

Your Name: Create a Pen Name or

Barnes & Noble.com Review Rules

Our reader reviews allow you to share your comments on titles you liked, or didn't, with others. By submitting an online review, you are representing to Barnes & Noble.com that all information contained in your review is original and accurate in all respects, and that the submission of such content by you and the posting of such content by Barnes & Noble.com does not and will not violate the rights of any third party. Please follow the rules below to help ensure that your review can be posted.

Reviews by Our Customers Under the Age of 13

We highly value and respect everyone's opinion concerning the titles we offer. However, we cannot allow persons under the age of 13 to have accounts at BN.com or to post customer reviews. Please see our Terms of Use for more details.

What to exclude from your review:

Please do not write about reviews, commentary, or information posted on the product page. If you see any errors in the information on the product page, please send us an email.

Reviews should not contain any of the following:

  • - HTML tags, profanity, obscenities, vulgarities, or comments that defame anyone
  • - Time-sensitive information such as tour dates, signings, lectures, etc.
  • - Single-word reviews. Other people will read your review to discover why you liked or didn't like the title. Be descriptive.
  • - Comments focusing on the author or that may ruin the ending for others
  • - Phone numbers, addresses, URLs
  • - Pricing and availability information or alternative ordering information
  • - Advertisements or commercial solicitation

Reminder:

  • - By submitting a review, you grant to Barnes & Noble.com and its sublicensees the royalty-free, perpetual, irrevocable right and license to use the review in accordance with the Barnes & Noble.com Terms of Use.
  • - Barnes & Noble.com reserves the right not to post any review -- particularly those that do not follow the terms and conditions of these Rules. Barnes & Noble.com also reserves the right to remove any review at any time without notice.
  • - See Terms of Use for other conditions and disclaimers.
Search for Products You'd Like to Recommend

Recommend other products that relate to your review. Just search for them below and share!

Create a Pen Name

Your Pen Name is your unique identity on BN.com. It will appear on the reviews you write and other website activities. Your Pen Name cannot be edited, changed or deleted once submitted.

 
Your Pen Name can be any combination of alphanumeric characters (plus - and _), and must be at least two characters long.

Continue Anonymously
Sort by: Showing 1 Customer Reviews
  • Anonymous

    Posted August 9, 2002

    How to get this book?

    I would like to get this book for free,if you would be kind to send it to me.I haven't any payment card which is valid there.But I would like to get this book,to show it in my Company to my boss and I hope that my Company will order next books from you soon. If you think that you can do it,please contact me at my email

    Was this review helpful? Yes  No   Report this review
Sort by: Showing 1 Customer Reviews

If you find inappropriate content, please report it to Barnes & Noble
Why is this product inappropriate?
Comments (optional)