Memoirs of a Developer

Traditional phone systems are susceptible to a number of attacks. Such attacks more often than not involve the use of specialised equipment that can tap into the phone lines. The more common of these being cutting into the phone lines using clippers, evesdropping on the other side of the switch, or using a radio receiver tuned to the right frequency to pick the ongoing microwaves or finally you can evesdrop at the microwave or satellite phone links.

Voip on the other hand is a completely new concept. With the advent of this technology, voice calls are no longer vulnerable to the same attacks that the old phone systems were. Voip unlike telephone systems works on the same principles (since it is transported over) as the internet. Now the major flaw of the IP system is that the packets sent over the internet can be intercepted across any of the stops that the packets make. This provides an opening to hackers to try tap into a conversation by attempting to hack into the conversation in pretty much the same way that they would try to have a normal “data pipe” on the internet.

Normal voip calls are transmitted over unencrypted sockets. This can be fixed by using one of the new secure voip clients which encrypt the information to ensure that no one other than the intended person on the receiving end can listen on the conversation. Encrypting the information makes the information hard if not impossible for anyone without the generated key to decipher what is being transmitted.

There are a number of phones that support this kind of encryption. The one I would trust the most would be Zfone which was written by Philip Zimmermann who was also the author of PGP encryption (for those who are new to the encryption marker, its one of the strongest encryption standards on the market). This technology is still just starting to grow so it would be advisable that if you are really paranoid about your privacy, you might want to give Zphone a try.

Links:

• Zfone
• Encryption
  
• Schneier on Security