Internet Phone and Video |
Chapter 12Internet Phone and VideoIn Lesson 5, "Understanding E-Mail," you learned how cheap it is to communicate via the Internet. The cost of sending messages back and forth to relatives, friends, and colleagues is practically nothing when you figure the number of messages you can send in a short amount of time. Now consider sending voice rather than text across the Internet. Add into that the ability to carry on real-time conversations, and you're talking about using Internet phone software. Internet phones, or Web phones as they are sometimes called, enable you to talk directly to another person halfway around the world simply by using the Internet. In this lesson, you can find answers to the following questions:
Internet phone use is beginning to grow; new software and increased features will likely be available soon. You should find, however, that the tips in this lesson apply to most Web phone packages. Theory Behind the Web PhoneSince the beginning of the Internet, data has been transmitted from network to network and from computer to computer. Because the human voice can now be digitized, it only seems natural that tools for transmitting speech along these networks would be developed. Enter the Web phone market. Now you can bypass the long-distance phone companies altogether. The global telecommunications network has been replaced by the collection of networks known as the Internet. A digital data signal that represents a voice is sent to the next computer rather than an analog signal that connects to the handset of a standard phone. Making a call to my brother Dave, for example, is no more difficult than checking a Web site for the day's sports highlights. I call up Dave's computer by using my Web phone's phone guide, by typing in his IP address, or by selecting his name from a list of current online users. Assuming that Dave is online at the time and that we are using the same Web phone software, he is notified by the standard phone "br-ring" or some other signal. Dave can accept my call with the click of a button, and we can save ourselves the cost of a long-distance phone call. If only the process were that easy every time. Later in this lesson, I'll give you tips to make calling your friends, relatives, and so on rely less on luck (in my case, Dave happened to be online) and a lot more productive. Now back to the theory: When you speak, your Web phone software digitizes your voice into packets of data. These packets are transmitted through your modem, across the Internet--bouncing from server to server, to your caller's modem, through his or her software, and finally back into an audible signal--or your voice. The main bottleneck with this scenario is the bandwidth required. For a true telephone-quality connection, you would need to transmit about 8 kilobytes of data per second. Unfortunately, a typical 28.8 Kbps modem can handle only around 3K per second. What the hardware is lacking, you can try to make up with software design. Web phone vendors have tried to pump more information into every kilobyte of data they transmit. Every Web phone application now uses some type of audio compression software, or codec. The codec receives your analog voice signal from the microphone and compresses it into a digital signal. On the opposite end, the codec converts the digital signal back into an analog signal that can be reproduced at the computer's speakers. New Term: Codec: This term is short for compression/decompression. A mathematical algorithm is responsible for encoding an analog signal into digital form. It also decodes a received digital signal into an analog signal. Connection TipsIn this section, I provide a few hints to make connecting and conversing with an Internet phone easier and more enjoyable. If your Internet service provider offers static or fixed IP addresses, get one. A static IP address is one that doesn't change every time you dial into your provider. Connecting with another person is easy if you always know his or her IP address. With a standard, dynamically assigned IP address, you lose one form of dialing directly to that person's computer because his IP address changes with each connection to their ISP. Many Web phone vendors maintain servers listing the online users of their software so that connecting to another user is easier, but these servers can go down, leaving you little hope of making a connection. I highly recommend using at least a 28.8 Kbps modem. Any lower speed does not give a reliable connection. Transmission of a conversation over even a 14.4 Kbps connection leads to garbled speech and lower sound quality. When you want to place a Web phone call, plan a rendezvous time and place with your caller. Not many people can afford to sit and wait for the Web phone to ring. Nor do they enjoy searching through hundreds of chat rooms for a person to talk to. Logging onto a vendor's server waiting for a person to call can also lead to your receiving miscellaneous calls from strangers wanting to talk to anyone to test their installation. Use settings that maximize the performance of your software. Choose the correct codec for your connection speed. Identify your correct hardware settings within the Web phone application. Also, adjust the input and output settings on your microphone and speakers to reduce echo and feedback. Headphones are great when you're using a Web phone application. With some connections, you may experience distortion or transmission delays. Headphones place your ears closer to the source. So, from this vantage point, you can often more easily understand what the other person is saying. Using headphones also means you don't have to worry about possible feedback effects and distortion from microphone and speaker interaction. You should purchase a full-duplex sound card if you don't have one. This type of sound card enables you to carry on normal conversations with your caller. Full-duplex cards allow both users to talk simultaneously. Half-duplex cards, which are installed in all but the more recent machines, can carry only one speaker at a time (similar to a CB radio). During installation, most Internet phone applications will tell you what type of sound card you have installed in your computer. Last, but not least, speak clearly and slowly directly into your microphone. Most Web phone software is voice activated, so as long as you're talking, it is transmitting. If you lower your voice and speak softly, you may not register as talking within the application, and nothing you say will be sent to the other person. A Typical Web Phone ConversationI've covered the basic principles behind a Web phone, but I haven't talked about how to use one. As an example, I'll explain how to use the most popular Web phone application, Internet Phone by VocalTec, to demonstrate the following:
Because not all phones offer the same features, some phones may not offer all the options of Internet Phone. I chose Internet Phone for this demonstration because many magazines have rated it their top choice for Web phones. You can download a seven-day trial version from the VocalTec Web site (http://www.vocaltech.com), shown in Figure 12.1. The VocalTec Web site provides the demo version of its Internet Phone software. Dialing into Your ISPNone of this phone software would do you much good without a connection to the Internet. To begin the example, you need to connect to your Internet service provider.
You don't need to do anything out of the ordinary when you dial in. Just follow the directions that the ISP provided when you opened your account. The Web phone application runs over the same protocol as many other Internet applications. Your ISP should already be capable of using Web phone software, so no changes should be required on that end. A corporate firewall, on the other hand, may not allow use of the particular port that Internet Phone uses. You should contact your system administrator if you run into problems connecting to the Internet Phone directory servers. Launching the Web Phone ApplicationWhen you run the installation program, a copy of the Web phone application and all the files needed for the program to run correctly are installed on your hard drive. Locate the Internet Phone application and double-click it. If you're using Windows 95, you can also find the Internet Phone application listed in your Start menu. After you establish your Internet connection through your ISP, launching Internet Phone opens two Internet Phone windows. One is the phone control window, and the other is the Global Online Directory (GOLD) window.
The software tries to connect you to one of the 20-plus Iphone servers around the world. These GOLD servers are in constant contact with each other and provide a real-time list of the current users. By connecting to one of these servers, your name is simultaneously added to the Online Users list on all the other servers, as you can see in Figure 12.2. The Global Online Directory lists all the current Online Users and Chat rooms. Connecting to one of the GOLD servers may take a few minutes. You can watch on the screen as the software connects to the server. If the server has too many users or does not respond, another server is called until a connection is made. Controls and DisplaysThe Internet Phone control window displays an animated assistant and three primary buttons, as shown in Figure 12.3. The animated assistant serves to notify you of incoming calls, displays your current online status, and identifies users during a conversation. The animated assistant in the Internet Phone control window is waiting for a call. By clicking the Answer button, you can accept an incoming call, like picking up the receiver on a normal telephone. After a call has been made, the button changes to Hang Up. You can click the Hang Up button to end a conversation. The Hold button mutes your microphone, not allowing the other user to hear you. You use the last button, Redial, to call back the last person dialed automatically. To the left of the animated assistant are four more icons (starting at the top):
The whiteboard enables users to draw, diagram, or collaborate using a graphics tablet. Under the animated assistant are three additional panels. They display real-time user information during your conversation. The panels may not always be visible when the application is launched. Click the appropriate button to toggle any of the panels open or closed. The arrow on the button signifies which panels are opened. The Call Center gives you direct access to the Online Directory, your Personal Directory (like your phone guide), and the Web Directory. It also lists the individuals whom you have called for quick reference back to them. The Session List keeps a running tally of your current connection status as well as any previous calls you have placed. The Statistics panel records a real-time log of incoming and outgoing data signals, the codec used, and the transfer rate. This panel is good to use if you notice your connection is hampered with sudden dropouts. New Term: Dropout: A dropout is a sudden loss of digital signal that cuts off the person speaking. A dropout is generally caused by incorrect audio settings on a user's microphone and speakers. Global Online DirectoryThe Global Online Directory (GOLD) window provides a list of individuals who are currently online. It also maintains the status of chat rooms used by callers. Chat rooms are great places to rendezvous or just find someone to talk to. Private chat rooms are "unlisted" and can be created when you want to talk to family or business associates. Access to these rooms is limited to only those people who know they exist. Dialing the RecipientYou can place a call to another person in the following different ways:
After you initiate the call, the animated assistant dials the number. Just to give you some familiarity, a telephone rings until the other person accepts your call. Your conversation can begin when the connection is complete, so watch for the signal from your assistant. Receiving a CallIf you are online, another person can place a call to you. If this should happen, you may be notified in the following different ways:
To accept the call, click the Answer button on the Internet Phone control window, as shown in Figure 12.5. The animated assistant tells you that someone is trying to call.
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