There is a Digital Telephone in your future!

Even though you probably don’t currently have digital telephony or Voice Over IP (VoIP) service in your home or business, chances are that you have already made a VoIP call without even realizing it. Additionally, many of the homes and business that you are calling already have digital telephony. Why the change VoIP? The change is principally driven by cost in the residential market. Telephone cost reductions will generally be in the range of  30 – 50 percent depending on your current cost. There are additional benefits for business, such as enhanced system administration and detailed web based billing records. The introduction of VoIP is also driving down the cost of traditional circuit switched telephony.  So in many cases, consumers and businesses can get additional telephone cost savings just by knowing the rate plans for VoIP and traditional telephony.

How does VoIP Work?

Let’s start by taking a look at traditional telephony. In telephone circles, this is called Plain Old Telephone Service (POTS). Everyone is familiar with the operation of POTS, so let’s take a look “under the hood.” 

The diagram below shows the configuration for a local (same town) telephone call. The call starts with the person starting the call (Originator), picking up the phone. Lifting the phone sends a signal to the serving telephone office (Central Office), indicating the need for service. The Central Office will send a dial-tone to the Originator of the call. Dial-tone indicates that the Central Office is ready to receive dialed-digits. In this case the originator will dial 7 digits for a local call. The first three numbers of the number defines the Central Office for the party being called and the last 4 digits represent the actual phone address of the person being called. A digit analysis program in the Originating Central Office will analyze the dialed-digits and select a circuit to connect the two telephone offices together. Once the Central Offices are connected, the called-party or terminating phone will receive ringing from the terminating Central Office. Once the phone is lifted by the terminating party, all of the circuits between the two telephones are connected and the two parties can now talk. If both of the parties hang-up, the circuits will be disconnected and the call ended.
 

Since you are familiar with operational aspects of POTS service, you will notice very little difference operationally between VoIP and traditional phone service. VoIP calls can  also use the traditional phone network to terminate calls. There are also call scenarios where the entire VoIP call is completed over an Internet connection. Let’s take a look at  a VoIP only call. Note that this is a simplified diagram and the call processing is in the Internet Cloud in the middle of the diagram. Also note that this configuration is exactly the same as the configuration for you data IP network. In fact you internet communication travels over this same path.

Operationally, the Originating phone goes off-hook and a request for service information packet is sent to the internet. A gateway server on the internet returns a packet that tells the IP phone to turn-on dial-tone. The Originating caller dials the digits and the server on the internet analyzes the digits and determines how to communicate with the terminating phone. Note: each phone on the internet has an IP address, so communicating the phone is a matter of determining how to route packages of information to the phone.  Once the terminating phone has been located, the internet server will send a packet of information to the phone telling it that a call is coming in. The terminating phone will turn-on ringing and the called party will pick-up the phone. Once the phone is answered, a connection path will be established between the two phones and the callers can communicate. Note, this is all possible because the IP phones can convert sound to digital packets of information suitable for transmission over the Internet.

 

Three ways to complete a VoIP Call:

 Since most business and residential users already have an investment in analog telephones, it is only natural to reuse this equipment when transferring an existing installation to VoIP. This is done through using a Analog Telephone Adapter (ATA), sometimes called an ATA gatway. These devices enable you to make use of your existing standard analog phones. You simply plug your standard handset into the ATA (gateway) then connect the ATA to your  internet connection, enabling you to make VoIP calls. An ATA takes the analog signal from your standard phone and turns it into a digital signal ready for transmission over the internet. Some ATAs (gateways) come with additional software that is loaded onto a host computer, enabling you to configure it for VoIP accurately.

IP Phones – These handsets look just like normal standard handsets. They have an RJ 45 Ethernet connector instead of the standard RJ 11 connectors. These phones have all the necessary software and hardware to handle VoIP calls already built in. They connect directly to your router, providing a very fast and cost effective entry into the world of Voice Over IP.

Computer to computer – This is the easiest way to make use of the VoIP technology. There are many companies offering cost effective software that you can use for this type of VoIP. Usually the only charge you pay is the monthly one from your internet service provider, even for long distance calls. All you need is a microphone, speakers, a suitable sound card and a fast internet connection. SKYPE, MSN Messenger and Yahoo Messenger provide this kind of service. Both parties need to subscribe to the same service. This is great tool for reducing long-distance costs as long as communication is kept to people on the same service. These services also provide for video communications.  You will need a web camera to take advantage of the video capability.

What do you need to get started with VoIP. 1) you need broadband service. VoIP rides on your existing internet service. 2) you will need a VoIP provider such as Vonage or sunrocket, AT&T Call Advantage or Time Warner (there are many more). These services provide administration and call processing logic for your service. 3) If you are going to use your current phone equipment, you will need an Analog Telephone Adapter. Lastly if you are going to apply this technology to a whole house or business, you may need a consultant to help sort thing out and provide installation support.

Bottom line, Digital Telephony is in your future and the drivers are low cost telephone service and advanced features such as video conferencing.