Security of data is a very important feature of VoIP services.
There are two main areas where Security needs to be considered
1. Connection to the VoIP / SIP registration server. SIP generally uses three protocols for connectivity and message handling between the SIP server and clients (phones). These are UDP, TCP and TLS. UDP is a stateless protocol where each communicaiton is sent to the server and an individual acknowedgement is sent back. If packests are lost then messages can be resent again and again. TCP and TLS form a session between the client and the server. TLS is the secure version of TCP with all messages between the clients and the server being encrypted in much the same way that websites are protected with HTTPS.
2. The voice traffic between the devices. RTP is the protocol used to manage the actual media (video and/or audio) call between the two devices. SIP uses a standard called SRTP to encrypt the media traffic in addition to the SIP message traffic.
Irish VoIP supports TLS and SRTP.
