As of this writing, there are three basic types of VOIP that exist today. The first is ATA, or Analog Telephone Adaptor. The second is computer to computer and includes Internet software applications such as Microsoft NetMeeting and Skype. The third, and mostly used in a business environment, are IP phones. IP phones are currently expanding and will soon include IP WiFi as another alternative to standard cell service but it is still in development.
ATA, in a nutshell, is a small device that connects to your regular PSTN telephone and then connects to your computer for digital signal traversal over the Internet. With this service, you connect to your computer via your regular telephone. Your telephone sends the digital telephone signal to a receiving station that changes the signal back into analog at the receiving end and into the local PSTN network.
The second type of VOIP is computer-to-computer VOIP. In this style of IP telephony you are connecting directly between two computers over the Internet without the use of any external sources other than your computer and normally a broadband connection. Some services will work with modem technology but, due to an analog modem’s inherent lossy nature, it doesn’t sound very good. With services, such as Skype, Net2Phone and Netmeeting, you are capable of communicating with anyone at their computer throughout the world for just the fee of your broadband connection.
An additional feature within computer-to-computer VOIP is the ability to connect to external telephone numbers throughout the world for a small fee to connect to the distant end PSTN. It’s sort of a hybrid between ATA and computer-to-computer. I guess you could call it CTA or Computer To Adapter, but no official name has been settled on as of yet. There are also a few USB capable telephones that will connect directly to your computer and are set up to work directly with these programs and will even act as a satellite speaker for you computer. These telephones are fully functional with multiple streaming media types.
This crossover was initially done with Netmeeting, but the signal quality was very poor and the per-minute connectivity charges were cost prohibitive. With the newer services that incorporate distributed processing, similar to the SETI@HOME project, the quality of signal has increased to the point that it dwarfs the sound quality of even the best PSTN telephone.
The third type of VOIP is considered to be IP telephones. They are similar to your regular telephones but have added feature capabilities, better sound quality and, in the case of larger businesses, a larger return on investment. What’s so special about them? Well, they plug directly into your router as the digital conversion is built directly into the phone. From your router, the digital telephone signal is sent to the Telephone Company, or telco, where it is split from your regular traffic and sent along the already digital backbones of the telco to the destination.
Something you may or may not realize is that you are already using a smattering of this service when you make a regular telephone call. Unless you are making a strictly local call, your analog signal is converted into a digital signal at the telco to decrease bandwidth size and increase signal quality. It is then transmitted from one station to the next as a smaller digital signal until it reaches the destination “hub” and then converts back into a digital signal.
Currently, Nortel Networks has the daunting task of upgrading all of the legacy equipment onto a completely digital network structure for what is frequently referred to as the “Baby Bells”, or what was left over after the last mandatory restructuring of AT&T, which is now Verizon. This will eventually enhance the PSTN system to a digital network that will allow DSL and other broadband services to all of their customers. One reason for the rush is that cable companies are already offering complete digital packages, including telephone service to your doorstep. I should know. I’ve got the package.
What makes all of these technologies similar is that the all start as analog voice, get transferred into a digital signal, traverse a telco backbone to reach their destination and are broken out into an analog signal at the distant end. As I have shown, the methods for doing this are as varied as the many companies providing VOIP service. Currently, the standards for this emerging technology are lax at best and the only business standards fall within IP telephony. In fact, the VOIP technology used for business has it’s own primary standard, Ethernet. 802.3af, and was finalized in early 2003. Cisco was one of the first companies to comply.
Since this is a Cisco class, I’ll cover the IP Telephony solution that they provide. First, they have broken their solution into four primary components: Infrastructure, IP Phones, Cisco Call Manager and Voice Applications. This solution is in no way all-inclusive and is extremely pointed towards purchasing Cisco products. Heck, the source is from the Cisco website. It’s basically a well-constructed commercial. So here goes:
Infrastructure - Includes PSTN gateways, analog phone support, and digital signal processor (DSP) farms. Cisco IP Telephony infrastructure solutions can support multiple client types such as hardware phones, software phones, and video devices, as well as provide options for integrating traditional PBX, voice mail, and directory systems.
IP Phones - Cisco IP phones combine the functions of a traditional telephone with an Ethernet connection and optional customizations such as access to stock quotes, employee extension numbers, and Web-based content. The Cisco IP SoftPhone is a Windows-based application for the PC that offers IP functionality in conjunction with a Cisco IP phone or as a standalone end station.
Cisco Call Manager - This software-based call-processing agent extends enterprise telephony features and functions to packet telephony network devices such as IP phones, media processing devices, VOIP gateways, and multimedia applications.
Voice Applications - Voice applications are physically independent from the call processing and voice-processing infrastructure, and they may reside anywhere within your network.
There are a lot of cool toys included within these four components. The IP Phones are effectively a cross between a laptop and a PDA with a telephone receiver and a switch-bank. The Voice Applications are capable of utilizing most of the IP Telephone functions but only on a laptop. They even have full support for WiFi IP telephony. If your company has the money to spend then Cisco is almost always the right choice, IP Telephony is no exception.
So, what specifically are the finer points of VOIP? Well, there are a lot of reasons to move your infrastructure over to an IP Telephony infrastructure. Just a few are a cleaner sound, smaller long-term costs, no long distance charges and less bandwidth usage.
The clarity of a digital signal lies in the ability of a digital signal to be repeated, or rebuilt instead of an analog signal’s limitations to an attenuator. All an attenuator does is strengthen the signal but does nothing to clean the signal. Over long distances this can turn a nice looking sign wave into something that resembles more of an earthquake. A digital signal, on the other hand, only looks like a one or a zero. There’s not much room for interpretation there.
After your initial purchase, you will begin to reap the financial benefits of a more efficient telephone system. You will have fewer lost calls, better organization, and increased productivity. As an advertising tool, this will bring into play potential repeat customers. Remember, if a customer likes the way you handle his or her call there is a greater opportunity for repeat business.
Another monetary boon is the lack of long distance telephone charges. Since all of your new calls are technically being converted into a digital broadband signal, no matter where you call, or how long you talk, it is considered bandwidth and not long distance. There is still a charging system for IP telephony bandwidth usage but it is metered by usage, not destination. This can be very helpful if your business does much overseas or intra-state business. All calls are local calls.
The last benefit I would like to discuss is primarily for the telco side of things. Since an analog signal is so much more intricate than a digital signal, it costs your telco much more bandwidth to transmit. Think of it like the difference between a WAV music file and an MP3 music file. The WAV, although nearly of analog quality, is much larger than the compressed, digital style format of an MP3. Due to the increased bandwidth of the Internet, the standard telco lines have started to become overtaxed and upgrades have been needed. By using all digital backbones the telcos have been able to slow the tide of the ever-increasing need for more bandwidth.
As with most anything that has positives there are a few negatives as well. VOIP is no exception to the rule. It is an emerging technology and has a few kinks to work out as well as some inherent difficulties. Among these are: the initial overhead, the untested technologies, uncertainty of governmental regulations and its low popularity due to under education on the subject.
I believe sticker shock is the term most often used when looking at how much some of the things you may need to purchase to get your VOIP network up and running. A bargain basement phones will run you about 200 dollars per phone and an IP teleconferencing phone will run about 1,000 dollars. This is just the beginning of your costs as voice gateways cost much more than that. If you are planning on buying into a complete IP Telephony system come prepared with a hefty checkbook because the buy in costs are not cheap.
Since this is an emerging technology there will be changes. As I have demonstrated above, the barriers between the three different types of VOIP are becoming hazier as we speak. What will not work with one plan will work under another without any rime or reason. As with other technologies, the posturing will stabilize and most companies will adopt a generally excepted standard. Usually, what will happen is one standard will become more popular than the others and become the adopted standard. Unfortunately, it’s not always the best standard and usually comes from the company with the most overall popularity and trust with the core of businesses.
Something else in the forefront of many VOIP companies, such as Vonage, are the unwritten government regulations for how they are to operate. Since VOIP is essentially turning a telephone service (taxable under federal law) into an Internet service (not taxable under federal law). Since digital voice packets are different from standard data packets they can be filtered at the router or voice gateway and are being tagged by all digital voice products on the market today as VOIP for potential monitoring. This would, in effect, turn VOIP into a telephone service and therefore classified telephone service, monitored as a phone service, and taxed as a phone service.
Therein lies the quandary. If we are gong to tax one form of data service should we be taxing all data services? There are some states that are already classifying this as a telephone service and trying to sue some of the VOIP services for telephone taxes by bandwidth. E-mail could be classified as a similar form of communication some day and therefore taxable. One day we may see an Internet tax as well. It’s all about the services that are available to the user through the government. If the government begins to control things like pornographic or questionable material on the Internet then we would feel safer to allow our children on our computers but we would suffer both restrictions on where we could go, say or do and also have to pay taxes to support the system. Digital voice is no exception to this.
The last problem I see with VOIP technology is that of under-education on the subject. You use it every day and just don’t know about it. There are capabilities through VOIP to completely do away with the standard telephone numbering systems. Imagine logging into any telephone anywhere in the world with a simple user name and password. Since my company uses VOIP services, I can walk up to any telephone on the network, punch in a number and instantly have my telephone extension connected to that phone. Now imagine putting just that service availability to the entire United States, or even the world. I know that appears to be extremely forward thinking but it is quite possible with VOIP technology.
To parallel this to Linux would be fairly accurate. People don’t understand the basics of Linux so the prefer to use an operating system they understand better instead. Some believe that Windows is the way to go and others believe that Mac is more intuitive and easier to use. Use Linux? That’s for geeks! I use Linux Fedora on one of my computers at home. My six-year-old son loves it. As soon as that computer became his I put it on there to see how it would do with a basic user. We’ve never had a problem. My wife hates it. It doesn’t work the way she thinks it should. When she clicks a button it doesn’t perform the same as a Windows machine would. She’s been educated to use a windows machine. Most of us have been educated to use an analog telephone and analog services. I’m sure my six-year-old son would have no problems picking up on it. In fact, when my Skype rings on my computer he runs up and tells me I’ve got a phone call, just like an analog phone.
Basic VOIP Information
Computer VOIP Service
Computer VOIP Service (I use them.)
Nortel Contract Information
CISCO Systems VOIP Information Sheets
Minnesota Judgment Against Vonage