I am IT engineer and I work also in IP telephony. I decide to write this article based on experience from the field where users asks me, why I replace old phones and what  will be advantage on new IP phones.  I find the explanation of SIP or H.3232 technology is very difficult to understand, especially for people over 50′s and I decide to find a way to explain that could understand anybody.

At the beginning a little history about telephony:

We are familiar with telephones from long time ago, exactly from year 1870. The first inventor Alexander Graham Bell designed devices that could transmit speech electrically (the telephone).

In the mean time till today happened a lot of new things on the telephones. After the invention of mobile phones we thought nothing new could be invented.

But, there is always something that we can make better. If not better it could be cheaper. And IP telephony (VOIP – Voice over IP protocol) can make calls very cheap in some ways also free of charge. And what is the difference at IP telephony vs. »classical -PSTN« telephony? We don’t need to connect our phones to special outlet and service provider  don’t need to place additional wire to our apartment. We can use pair of wire or much better fiber optic connection for telephony, TV and internet connection. This is view from user site, but if we are looking from provider site, we can see big difference in technology.

Now we find what is media used for IP telephony (VOIP – Voice over IP protocol) and the next question if we already have internet connection is what IP telephone to buy.  Do we really need new telephone or we can use old one?  I believe that everybody wants new phone, because people likes new things.  But there are still a few people who like their old phones. Inventors find solutions for them too, which is called media converters.

 Media converters convert our voice from analog signal to digital and this one is converted to IP world. The box where we connect old phone on one site and the internet on the other site we call media gateway.  Simple!!! Not really, but in this article we will not explain in details how technology works. It is important that you understand basics.  IP telephone we can connect directly to the internet and it should work. And here is first advantage. If you travel to different places around the world, you can take your phone with you. Practical? No of course not. But most people today travel with notebooks and notebooks are usually connected to internet. Another solution and advantage of IP telephony (VOIP – Voice over IP protocol) is soft phones. This is software installed on your system and this software act like phone. Another good thing is that we can find on the internet software for free. Software for free, calls almost  for free( like you call from own country) , you can forward your calls also to mailbox… everything one big advantage.


Now, let we say that we decide to buy new phone. We can find a lot of producers of IP telephones and my experience  is that we have to search to find bad quality telephone. It is important to buy right IP telephone, because they use different technologies. But your provider will tell you what to buy if you ask them. Oh, and I almost forgot to tell you. Most of providers give IP phone for free.

If you are interested please research voip business solution.

Term – VOIP Voice Over IP explanation

VoIP (or IP Telephony, Internet Telephony, DSL Telephony) is a used term for the technology that use the Internet Protocol to exchange voice and other communication services. So far this services mainly have been carried over the public switched telephone network (PSTN)

VOIP and security

The question about security is always in front of everything. However if you are worried that somebody can listen your phone conversation……I really don’t know what is good answer. Of course everything is possible especially if you don’t know what you are doing, for example if you have your soft phone on your laptop and you are connected to wireless router without password for connection. If you have somebody in your company and he is familiar how to connect between your phone and switch or how to make port mirror on switch and capture data. Listening somebody on IP telephony is possible. But I really don’t understand why some people are so worried. In times of analog telephony was listening
conversation on telephone lines much easier. It is throe that you need access to the wires and connect with small speaker and listening.  Access to the wires…..just look around it was not so har to find them.

How can we protect from bad guys on IP world and telephony? If the data is encrypted there is almost not possible to decrypt them and listen conversations. So if you think there is possibility and somebody near you is suspicious you can protect yourself with data encryption.

I will explain on some practical example from field. Regarding to the company use for their employee VPN connections and they can work from home or connect to the company servers from anywhere, this type connections is enough secured also for voice transfer. When you establish VPN connection form your computer to your company you just have to change IP for your SIP gateway on your soft phone and voila, you are connected to your IP PBX. In this case we use VPN client on your computer machine. Regarding I am good friend with administrator in my company we create VP N connection between my router and company router. That mean I can reach company VOIP gateway from home network. Of course I use also desk IP telephone. I don’t need to connect every time and start with procedure to establish VPN connection.

If you are regular user at some Internet Service Provider don’t be afraid. Nobody will listen your conversations, especially not your neighbor.

If you find too much words that you are not familiar with them (VPN, IP PBX, data encryption…) I can tell you that I have in short plan to write articles about Networks. You will find really basic explanations that everybody understands.