VoIP

How VoIP Works

If you've never heard of VoIP, get ready to change the way you think about long-distance phone calls. VoIP, or Voice over Internet Protocol, is a method for taking analog audio signals, like the kind you hear when you talk on the phone, and turning them into digital data that can be transmitted over the Internet.
How is this useful? VoIP can turn a standard Internet connection into a way to place free phone calls. The practical upshot of this is that by using some of the free VoIP software that is available to make Internet phone calls, you are bypassing the phone company (and its charges) entirely.


VoIP is a revolutionary technology that has the potential to completely rework the world's phone systems. VoIP providers like Vonage have already been around for a little while and are growing steadily. Major carriers like AT&T are already setting up VoIP calling plans in several markets around the United States, and the FCC is looking seriously at the potential ramifications of VoIP service.

Above all else, VoIP is basically a clever "reinvention of the wheel." In this article, we'll explore the principles behind VoIP, its applications and the potential of this emerging technology, which will more than likely one day replace the traditional phone system entirely.

The interesting thing about VoIP is that there is not just one way to place a call. There are three different "flavors" of VoIP service in common use today:

ATA - The simplest and most common way is through the use of a device called an ATA (analog telephone adaptor). The ATA allows you to connect a standard phone to your computer or your Internet connection for use with VoIP. The ATA is an analog-to-digital converter. It takes the analog signal from your traditional phone and converts it into digital data for transmission over the Internet. Providers like Vonage and AT&T CallVantage are bundling ATAs free with their service. You simply crack the ATA out of the box, plug the cable from your phone that would normally go in the wall socket into the ATA, and you're ready to make VoIP calls. Some ATAs may ship with additional software that is loaded onto the host computer to configure it; but in any case, it is a very straightforward setup.

IP Phones - These specialized phones look just like normal phones with a handset, cradle and buttons. But instead of having the standard RJ-11 phone connectors, IP phones have an RJ-45 Ethernet connector. IP phones connect directly to your router and have all the hardware and software necessary right onboard to handle the IP call. Wi-Fi phones allow subscribing callers to make VoIP calls from any Wi-Fi hot spot.

Computer-to-computer - This is certainly the easiest way to use VoIP. You don't even have to pay for long-distance calls. There are several companies offering free or very low-cost software that you can use for this type of VoIP. All you need is the software, a microphone, speakers, a sound card and an Internet connection, preferably a fast one like you would get through a cable or DSL modem. Except for your normal monthly ISP fee, there is usually no charge for computer-to-computer calls, no matter the distance.
If you're interested in trying VoIP, then you should check out some of the free VoIP software available on the Internet. You should be able to download and set it up in about three to five minutes. Get a friend to download the software, too, and you can start tinkering with VoIP to get a feel for how it works.

Next, we'll look at exactly how VoIP is used.

posted by cs @ 5:29 AM

Drawbacks

VoIP technology still has a few shortcomings that have led some to believe that it is not ready for widespread deployment. However, many industry analysts predicted that 2005 was the "Year of Inflection," where more IP PBX ports shipped than conventional digital PBX ports. This date has been moved on an annual basis and only now (mid 2006) is it beginning to happen. However, many purchasers of VoIP ports just want a phone, so the statistics can be misleading when interpreted by marketeers.


Faxes

One drawback is the difficulty in sending faxes due to software and networking restraints in most home systems. However, an effort is underway to define an alternate IP-based solution for delivering Fax-over-IP, namely the T.38 protocol. Another possible solution to overcome the drawback is to treat the fax system as a message switching system which does not need real time data transmission - such as sending a fax as a email attachment (see iFax) or remote printout (see Internet Printing Protocol). The end system can completely buffer the incoming fax data before displaying or printing the fax image.


Internet Connection

Another drawback of VoIP service is its frequent reliance upon another separate service - an Internet connection. The quality and overall reliability of the phone connection is entirely reliant upon the quality, reliability, and speed of the internet connection which it is using. Shortcomings with internet connections and Internet Service Providers (ISPs) can cause a lot of grief with VoIP calls. Higher overall network latencies can lead to significantly reduced call quality and cause certain problems such as echoing.

VoIP isn't entirely reliant upon internet connections, however. VoIP systems can also utilize regular telephone lines and business-grade connections like T1 for voice service. A few business VoIP Providers offer dedicated point-to-point T1 connections, thereby not relying on an internet connection for service. Although residential VoIP service typically uses only an internet connection, business-grade VoIP service can use a variety of connection methods to provide ongoing phone service.

Many VoIP users still maintain a traditional analog voice line (business line) which allows them to dial emergency numbers and utilize a traditional fax machine.


Power Outages

Another drawback of VoIP is the inability to make phone calls during a power outage, but this problem also exists with many phones used with conventional land lines and can be remedied with a battery backup. During a power outage you also have the choice to forward your phone to your cell phone or another phone number so you would still be able to receive calls.

If VoIP is used in solitary LAN (with no internet connection), it would consume more resources compared to a PABX.

Modems are now available with lithium ion battery backup so that you can use the service with no power.

posted by cs @ 6:44 AM

Voice over IP

Voice over Internet Protocol, also called VoIP, IP Telephony, Internet telephony, Broadband telephony, Broadband Phone and Voice over Broadband is the routing of voice conversations over the Internet or through any other IP-based network.

Protocols which are used to carry voice signals over the IP network are commonly referred to as Voice over IP or VoIP protocols. They may be viewed as commercial realizations of the experimental Network Voice Protocol (1973) invented for the ARPANET.ce providers. Some cost savings are due to utilizing a single network to carry voice and data, especially where users have existing underutilized network capacity they can use for VoIP at no additional cost. VoIP to VoIP phone calls on any provider are typically free, while VoIP to PSTN calls generally costs the VoIP user.

There are two types of PSTN to VoIP services: DID (Direct Inward Dialing) and access numbers. DID will connect the caller directly to the VoIP user while access numbers require the caller to input the extension number of the VoIP user. Access numbers are usually charged as a local call to the caller and free to the VoIP user(citation/example needed) while DID usually has a monthly fee. There are also DID that are free to the VoIP user but is chargeable to the caller .

posted by cs @ 6:55 AM

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posted by cs @ 5:23 AM

Cheap long distance calls

Cheap long distance calls

IP-telephony phone cards experience great popularity all over the world.
And it is not surprising, the newest information technologies offer Internet-users opportunities unattainable in the past.
IP-telephony is the most modern technology, that provides an alternative way of low tariff long-distance and international telecommunication by means of the Internet.
The use of Internet reduces the price of telecommunication multiple times!

How to call using IP-telephony?
You buy a virtual phone card on the Internet. The virtual phone card works the same way as a real phone card, but You receive a PIN-code — not a real card.
To use the card You dial specially assigned Access number, enter card’s PIN number after a prompt, and then dial the destination number.
This service contributes large savings and is especially important for firms and private individuals who frequently make long distance and international phone calls.
For example, one minute of usual phone conversation between USA and France costs 50 cents; with phone cards' use it costs 2.30 cents. Therefore you save up near 4.8 US dollars for each ten-minute conversation. Savings are significant, aren' they!

How to earn with IP-telephony?
As the question of savings is important for all peoples, IP-telephony becomes a very attractive direction for improving profits.
Within the framework of Affiliate Program WebSTel.com company suggests it’s partners to participate in two Programs: “The Referral Program” and “Own Shop” as well.
Using already designed templates You create your own phone cards Internet shop and receive 10% to 20% from each sale.

Who are IP-telephony phone cards major buyers?
It is very important to understand which Internet users are most interested in IP-telephony services. IP-telephony cards are used for calls from different countries, but the majority of customers are residents of the United States of America (97%) and IP (2%).
As a rule, residents of these two countries not only have an access to the Internet, but also use it actively to make purchases from Internet-shops.
Immigrants, students, tourists and visitors use long-distance communication for business or personal contact most frequently

posted by cs @ 8:43 AM