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Laptops All-in-One Desk Reference For Dummies- P66 doc

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Letting Your Fingers Do IMing 624 Figure 5-13: An Instant Messenger session from within AOL; you can also obtain an account and a copy of the program to use from a Windows desktop. 43 140925-bk08ch05.qxp 4/8/08 12:52 PM Page 624 Chapter 6: Communicating with VoIP In This Chapter ߜ Making phone calls without the phone company ߜ Getting a good VoIP when you need one ߜ Testing the quality of an Internet phone call ߜ Making beautiful music: VoIP and laptops W hen the Internet began to take hold in the 1990s, it didn’t take long for engineers to realize two important things about the plain old tele- phone system (POTS): ✦ Although some small, incremental improvements could be made to the system, it was no longer practical to use the original phone system for Internet communication. ✦ The new high-speed, high-capacity means of communication — includ- ing broadband connections like cable, DSL, and fiber-optic links — could be used for much more than merely transmitting data. Like what? Video, audio . . . and telephone service. Voice over IP (VoIP) comes in on the considerably more modern and capable coaxial cable strung by what used to be called the cable television company. VoIP networks are much more efficient than the old-style telephone network. ✦ They don’t need to open and maintain a sustained connection between the caller and the recipient; any two points on the Internet are never really connected, but instead are basically tuned into the data stream looking for packets addressed their way. ✦ Because a call is broken into millions of little packets, the network can easily share cables and wireless transmission media amongst thousands of users at the same time. ✦ Because the packets are digital, computers can squeeze all the air (and silence) out of a signal and send only the information that matters. By some estimates, a VoIP call that takes five minutes from beginning to end might occupy the equivalent amount of bandwidth required for about one minute of POTS. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 625 Rocking the Laptop Telephony 626 Rocking the Laptop Telephony Here’s how laptops can take advantage of Internet telephony: ✦ Making and receiving telephone calls through your laptop anywhere in the world where you can connect to the Internet. While the same may be possible with a cell phone, consider the fact that international calls on a VoIP system may cost only pennies per minute, while cell-roaming charges can easily run several dollars per minute. Some Internet cafés, including many on cruise ships, attempt to block use of VoIP, claiming that users are consuming too much of their band- width. In many cases the real reason is they don’t want to lose the rev- enue they otherwise receive by charging exorbitant rates for cell phone or satellite telephone communication. As a user, you should complain Pa Bell In the beginning, there was the telephone. Well, not quite the beginning: more like in the 1870s when Alexander Graham Bell . . . and four or five other inventors who were chasing after the same ring . . . created the first working tele- phone system. The system: a voice-actuated transmitter in the mouthpiece connected by a pair of copper wires to a tiny electrically driven loudspeaker in a device at the other end of the circuit. The signal traveled as an analog wave along the wire. This simple technology worked in 1876 when Bell summoned his assistant: “Mr. Watson. Come here. I want to see you.” And it still works more or less the same way today. Why do I say the original telephone works more or less the same way it did when Bell and others laid out its design? The technology is little changed, but the success of the system led to complexity and distance. Where pairs of wires ran directly from one building to another, the next step was to run the pairs of wires to a central switchboard where a human operator connected the incoming pair to an outgoing line to complete a circuit between two specific points. And then when neighborhoods and then cities and, finally, countries and continents became interconnected, there needed to be multiple switchboards (or mechanical switches) to con- nect local loops to long-distance trunks. And as the distance increased, amplifiers were needed to boost power. But the basic idea of the plain old telephone system, a pair of copper wires connecting Point A to Point B, still applies for standard telephone calls. Switching from one set of wires to another is handled automatically, and many calls change back and forth between analog and digital sig- nals along the way. Some signals are bounced up to a satellite in space to be redirected down to an Earth station, and other calls moved as flashes of light along a fiber-optic cable. But with a little explanation, Bell would have easily recognized his invention in its modern form. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 626 Book VIII Chapter 6 Communicating with VoIP Cutting the Cord 627 about any café that blocks VoIP and you should seek alternatives: other cafés, and other, unblocked Internet telephone providers. ✦ Most VoIP systems allow video conferencing as well as phone calls, again at very low rates. You can use the built-in webcam on many lap- tops or add a clip-on camera. ✦ You can use your laptop to listen to voicemail left for you on your home or office phone. You may sign into a web site that stores your voicemail, or you may have all voicemail sent to your e-mail address and get mes- sages by downloading your mail. Cutting the Cord Several years ago, I gave Mr. Bell and Mr. Watson their walking papers. I liter- ally cut the connection between my home and office and the copper wires that ran to the phone company’s central office about a mile away. On the island of Nantucket where I live and work, the first local service was intro- duced in 1887 and some of the infrastructure is still in use. I replaced the creaky (and more expensive) phone service with a VoIP tele- phone service. Same phone number, same phones within my home and office, and (nearly) the same quality of voice communication. It works this way: ✦ A coaxial cable comes into my office. It’s the same cable that brings “American Idol” and other drivel (sorry, I mean “entertainment”); a splitter sends one signal to the numerous TV sets scattered about and another signal goes to a cable modem. ✦ The cable modem output goes (via a standard Ethernet cable) to a VoIP gateway. This device, sometimes called an Internet telephone adapter, is similar to a modem in that it converts an analog signal from regular tele- phone devices to a digital signal that can go out over the Internet. It also compresses outgoing signals and decompresses incoming calls. In most setups, the VoIP gateway passes the Internet signal through to your computer or to a router that allows multiple laptops or computers to share the signal. Some VoIP providers offer a device that combines a router and telephone gateway in one box. A VoIP gateway is sometimes also called an analog telephone adapter (ATA). Within the box, an incoming analog wave from a standard telephone is elec- tronically sampled so it can be broken into small packets of digital information that travel over the Internet. Other functions provided by a VoIP gateway include call routing and signaling over the remnants of Bell’s public switched telephone network; this gives a dial tone at your end and rings the telephone 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 627 Cutting the Cord 628 at the number you’ve dialed. (Dialed? That’s a word that has lost its original meaning; yes, kiddies, us old folks used to use a rotary switch to “dial” a number.) The packets include data like your phone number, the number you’re calling, and the IP address of your connection to the Internet. Also in the packet are instructions to a VoIP gateway somewhere else in the world that converts the digital pieces back into an analog signal if the number you called is a tra- ditional telephone; you can also communicate from VoIP gateway to VoIP gateway and stay in digital mode all the way. The digital revolution dials a phone call Computers manipulate digital information. A character onscreen is represented by a number (or set of numbers). So, too, a sound’s volume or pitch of a sound or whether it is a high treble or a low bass tone is made digital. There are many advantages to converting Alexander Graham Bell’s analog waves to digital numbers: ߜ They can be made more precise. ߜ They can be amplified and sent great dis- tances without fear of garbling. ߜ They can be protected from corruption. And perhaps most importantly in this era of local area networks (LANs), wide area net- works (WANs), and the global Internet, digital information doesn’t need to be transmitted or received in a continuous and orderly stream. It can instead be broken up into pieces and reassembled at the other end. On the Internet, for example, a message from Point A to Point B that reads, “The check has been received” might (in logical terms) be divided into five pieces, each within a digital packet that includes the identity of the sender, the identity of the receiver, and a sequential number. The packets are cast out onto the Internet like marbles in a pinball machine and eventually reach their destination, where they quite possibly arrive like this: check [word 2] been [word 4] The [word 1] has [word 3] received. [word 5] The machine at the other end gathers all the pieces and reorders them into a sentence. If for some reason it finds a word missing from the sequence, it can request that it be re-sent. All of this happens within tiny fractions of a second, whether the two computers are across the room from each other and connected by wire, across the office from each other and communicating by WiFi connection, or on the other side of the world from each other and linked by dozens of different pathways includ- ing fiber-optic links, microwave transmission, and satellite uplinks and downlinks. A working VoIP system at a fixed location like your home or office doesn’t need a computer to operate. However, you get a number of advan- tages when setting up a traveling VoIP system. See the “Rocking the Laptop Telephony” sec- tion in this chapter for more information. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 628 Book VIII Chapter 6 Communicating with VoIP Cutting the Cord 629 In most cases, a telephone conversation initiated by someone with a VoIP system will travel most of the way to its destination using the Internet — a system that begins with the local cable to your home or office and then usu- ally moves across major cables or satellite connections before it gets near your call destination. And then the “last mile” may travel to the person you’re calling over a pair of copper wires that Bell would recognize. If both ends of a conversation are using VoIP, the entire interchange may travel over Internet facilities, coming in and going out over cable coaxial or DSL lines. I could have set up a very similar system using a DSL Internet service instead of a cable modem. Deciding POTS is the pits Here are some of the advantages of VoIP: ✦ VoIP service generally costs less than an old-fashioned POTS if you include long-distance call packages. Nearly all VoIP providers have com- pletely eliminated the distinction between local and long-distance calls and have also turned off the meter that charged for length of calls. You can make a phone call across the street or across the nation without regard to distance or time; just like the Internet, your telephone service is available to you all the time for a flat fee. (Some providers include “free” service to Canada in their package.) ✦ Calls to international destinations are generally very inexpensive. ✦ VoIP providers include a package of advanced telephone services including • Call forwarding • Call waiting • Caller ID • “Do-not-disturb” schedules • Speed dialing • Conference calling Most systems allow you to set up an address book on your computer or on a web site that helps you keep track of phone numbers and also inte- grates with the caller ID system; when someone whose name is in my address book calls me, my telephones display their name whether their number is public or its identity blocked. ✦ All providers also include voicemail; one especially interesting feature offered by some providers sends an e-mail with an attachment that includes your voicemail. I regularly use that feature to listen to my voice- mails using my laptop from anywhere in the world. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 629 Cutting the Cord 630 VoIP has some disadvantages, although technology is dealing with most of them: ✦ Because the calls are broken into packets, sometimes a slight delay (called latency) is built into the communication. You may have to teach yourself to wait a half-second before responding to someone who’s talk- ing to you; I sometimes apologize in advance to callers, explaining that I’m on an Internet phone line and I don’t want them to think I’m being rude if I occasionally seem to interrupt them. (It’s a good conversation starter, too; it shows others how technically advanced you are.) ✦ Some systems may deliver voice quality that is slightly less full than a standard telephone call. Your voice may sound tinny. ✦ When a VoIP call is in progress, the telephone gateway may grab a large portion of the available bandwidth which may slow down other tasks on the Internet. The faster your connection, the less likely you are to notice this effect. And you can also contact your VoIP provider and ask about available settings (downloaded over the Internet by a technician) that can adjust how much of the bandwidth can be claimed by the phone system. Your VoIP provider needn’t be affiliated in any way with your Internet service provider (ISP). The phone is just another device using the Internet. You can use an Internet service offered by your ISP or you can mix and match. ✦ If you use different providers for Internet and VoIP services, you may run into a “blame-the-other-guy” response if you have technical problems. The VoIP company may say their service is working fine and that the cable or DSL company is delivering an inferior connection; the ISP may claim that their signal is just fine and that the phone provider is offering subpar service. In my experience, I can push the phone provider a bit harder since they know I can easily change services; remind them of that and make them prove they’ve done everything possible to give you the highest-quality VoIP service. ✦ Your phone service won’t function if your home or office loses electrical power. Some providers, though, offer an adapter that comes with a built- in rechargeable battery backup that keeps the connection alive for sev- eral hours; you can also purchase your own uninterruptible power supply (UPS) and plug the phone adapter and modem into that device. If your Internet service goes down, though, your VoIP service won’t work even if the power is on. Be sure you understand how your VoIP provider handles 911 calls. Dialing that number still gets you to an emergency response agency, but unless you’ve registered an address with your provider — and you’re at that location — the information they receive may not automatically pro- vide them with your address. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 630 Book VIII Chapter 6 Communicating with VoIP Getting to VoIP at Home or Work 631 Many VoIP providers automatically require you to confirm your phone location any time they detect that their telephone adapter has been unplugged or has lost power (a possible indication that the phone has moved). This sort of safeguard doesn’t work with pure Internet services that don’t use a telephone adapter, such as Skype. A valuable feature offered by many VOIP providers is an automatic re-routing of calls to another number in the event your service isn’t working properly (because of a power outage or an Internet outage, for example). My VoIP provider automatically sends incoming calls to my cell phone if necessary. Finding VoIP services Dozens of companies, small and large, offer VoIP services. Some are divi- sions of major telecommunications companies that are trying to hold on to customers in one way or another: ✦ AT&T (CallVantage) ✦ Comcast ✦ Verizon Others are new technology companies that have little or no infrastructure of their own (other than computers) to manage routing and accounting for calls; these include companies like ✦ Skype ✦ Vonage ✦ Magic Jack In my experience, the old-line telecommunications companies generally offer a better product, although they may not be the least expensive services. Getting to VoIP at Home or Work Here’s what you need to use VoIP at a fixed location like your home or office: ✦ A broadband Internet service. This can come from a cable modem provider, a DSL service from a phone company or independent provider, or a fiber-optics service. ✦ A VoIP gateway (telephone adapter) and a broadband modem. Some VoIP providers offer both devices in one box. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 631 Getting to VoIP at Home or Work 632 Because VoIP systems use the Internet instead of telephone wires, you’re required to notify the Internet phone provider of your address so 911 and other emergency services can function properly. Anytime your phone adapter is turned off or loses power, you have to re-register your address. ✦ An account with a VoIP provider. These companies provide a tele- phone number or (in most cases) transfer an existing standard telephone number or cell phone number to their service. ✦ A laptop or desktop computer for system configuration and to manage the special features. You don’t actually need a computer to use a func- tioning VoIP system, and your computer doesn’t need to be powered on or running any software for the phone adapter and cable modem to pro- vide service. ✦ One or more telephones. In the simplest setup, you can merely plug a wired telephone into the standard telephone jack on the back of the phone adapter. But it’s also very easy to extend telephone service throughout your home or office. Here are two ways to do that: 1. Attach a multiphone wireless telephone base station to the back of the phone adapter. 2. Place additional phones anywhere they can receive a strong signal. And this way: 1. Disconnect your existing telephone system. 2. Go to the Network Interface. The old copper wires had come into your home or office here. 3. Unplug the incoming wires. 4. Change the wiring at the box. You should have a closed loop of a system. 5. Plug a telephone cable from your VoIP gateway into a phone outlet. You can then plug ordinary telephones into any outlet that formerly used the old phone company wiring. If the rewiring scheme sounds vague or frightening, it’s only because I want you to follow the recommendations of your VoIP provider. Ask them for techni- cal assistance in reusing your existing “inside” wiring. (Don’t be frightened — the electrical power in a phone line isn’t dangerous — but you do need to do the job properly, and some VoIP companies have differing recommendations based on their equipment.) 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 632 Book VIII Chapter 6 Communicating with VoIP Getting Quality VoIP 633 Getting Quality VoIP For a VoIP system to work well, you need ✦ A high-speed Internet connection ✦ A clean, well-performing network Troubleshooting Network congestion, poor-quality connections (wired or wireless), and atmospheric conditions can conspire to make your telephone conversation sound like it’s coming from the bottom of a deep well . . . in a hurricane . . . with six simultaneous conversations working their way into and out of the call at the same time. It shouldn’t be like that. Before you call your VoIP service support desk, do a bit of troubleshooting on your own: ✦ Does the signal seem to degrade under certain conditions — whenever you run streaming video from YouTube, for example? ✦ Does the signal seem fine in the morning but fall apart at 3 p.m. — just about the time the neighbors’ kids get home from school and start trolling the Web? ✦ Has your voice connection gotten worse since you moved your wireless telephone from one spot to another — such as the other side of the house? Each of these conditions, and others, has a different troubleshooting path to follow: ✦ Your telephone adapter may need to be re-set by your service provider to grab hold of more of the Internet bandwidth. ✦ You may need to upgrade your connection speed. ✦ You may need to fix or replace your plain old telephone system. TestMyVoip A number of online web sites can test your Internet connection with a spe- cial emphasis on technical problems that can affect the sound quality. Among my favorites is www.testmyvoip.com, which is offered by Brix Networks, a supplier of services and software tools to Internet providers. 44 140925-bk08ch06.qxp 4/8/08 12:52 PM Page 633 . Internet phone call ߜ Making beautiful music: VoIP and laptops W hen the Internet began to take hold in the 1990s, it didn’t take long for engineers to realize two important things about the. system for Internet communication. ✦ The new high-speed, high-capacity means of communication — includ- ing broadband connections like cable, DSL, and fiber-optic links — could be used for much. send only the information that matters. By some estimates, a VoIP call that takes five minutes from beginning to end might occupy the equivalent amount of bandwidth required for about one minute

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