One of the biggest concerns with VoIP is the lack of connectivity to emergency phone services (like 911) and the other is security in terms of privacy. Data transmitted over the internet is not always secure and there is no telling when someone might not be listening to your private conversations. Then there is the matter of someone hacking into a VoIP account.

Of course, the VoIP providers are constantly working on new technologies to increase the security features. The trouble however might not be at the consumer end but at the provider end. A common problem is when the VoIP server is not used exclusively for VoIP purposes. So all the other services (web server, FTP server, mail server, etc) are also functioning on it. That makes it a potential target for hackers. Similarly, the internet pipeline of a VoIP provider is often shared between VoIP services and other internet services, another potential security threat.

All these concerns become of paramount importance because more and more home users are switching over the VoIP because of the lower costs involved. The regular PSTN phone does not offer entertainment, news, online shopping, voice-based services and similar advantages that are available for free over a VoIP telephone.

Home users can use their regular telephone handsets and PSTN connections for VoIP after installing a device known as ATA (analog telephone adaptor) that converts the analog signals of PSTN phones into the digital signals required for internet based VoIP. Other options include phones that have built-in functions similar to a router or DSL modem. For people who own desktops or computers, it is possible to simply install a small software that functions as the equivalent of a telephone. The only hardware needed is a microphone and speakers or headphones to successfully use VoIP.

As of today, the VoIP market is more popular among the people who have VoIP enabled hardware because it a lot cheaper and more convenient to simply get an ATA adaptor for an existing PSTN connection than to get a digital phone or using VoIP through a computer.

One major advantage of VoIP over PSTN is that within a VoIP network, all subscribers can call each other free. This is applicable to long distance calls as well. Since the calls are routed over the internet there is no difference between calling someone in the same postcode or in a different country, as long as the VoIP network is the same.

With VoIP it is also possible to integrate voice and data requirements into a single service. So your ISP can be your VoIP provider and vice versa.

Stuart Drew is the owner of the popular PimpMyPageRank bog, which deals in all issues

technology, especially content, and income, generation in the online world.