VoIP has brought down the rates for long dist5A0ance and local calling so that many more people are trading in their PSTN telephones for spanking new digital VoIP phones. Since this is a new market there are many companies engaged in furious competition. This brings more services and lower costs to a greater number of people every year.

However, while there are several advantages to VoIP telephones in terms of lower costs and better features, there are the pitfalls of VoIP that need to be considered by everyone thinking of switching over to VoIP.

One of the disadvantages of VoIP is that there can often be delays in hearing from the other end making conversation difficult or confusing when there are echoes. These problems are noticeably absent from PSTN telephones. What happens in a VoIP telephone is that when you speak, your voice is taken as digital data that is compressed before it is sent over the internet. This compressed packet then reaches the other end and needs to be decompressed and converted back into sound waves. What happens is that sometimes because of a slow processor or due to insufficient internet bandwidth, the compression or transmission (or both) can result in delays. In the worst of cases it can even result in packet loss resulting in an "information gap" where what you say never reaches the other end. The typical delay in information processing in a PSTN phone is 10 milliseconds under most conditions. When a VoIP phone goes wrong, 590that delay can increase to a staggering 400 milliseconds.

This sort of problem does not matter for the casual user who is using a free service (not paying a monthly charge to a VoIP telephone company) and the nature of the calls is not critical, as it would be for a business. The problem reaches intolerable proportions when corporations (or even a small group of people) rely on VoIP for their business. Since most corporate networks operate behind a firewall for security reasons, one of the problems with VoIP is that, at present, they are not too friendly with firewalls.

Another problem with using one broadband connection for multiple users with VoIP features is that there is no way to determine which user gets how much bandwidth. This makes it impossible to know the exact requirements in terms of bandwidth versus number of users.

Most of these problems occur only under two circumstances. When the internet connection is too slow (there is no point in using VoIP if you use a dialup connection, you need a broadband connection at a minimum) or there are too many users sharing one broadband connection while operating from behind a firewall.

These are merely technical limitations that most VoIP providers are confident to solve in the neat future.