Viaccess is a subsidiary of France Telecom that produces Conditional Access Systems designed for use with digital Pay TV services. There are five main systems in use.
Viaccess PC2.3 is the first system to be developed, but it was compromised by hackers who could use software-modified receivers to watch subscription content for free. The Viaccess PC2.3 system was modified with two main modifications, TPS-Crypt and ThalesCrypt, TPS-Crypt added the use of Advanced Encryption System (AES) keys and switched keys every 12 minutes, causing a lot of inconvenience for unauthorized viewers. ThalesCrypt was developed as a more secure modification following the compromising of the TPS-Crypt modification. Viaccess PC2.3 is often referred to as Viaccess 1, being the first in the line of systems.
Viaccess PC2.4 is the second system to be developed. It was also compromised and is considered insecure. It is beaten with software-hacked receivers that can decode the transmission without the viewer being a paid subscriber. Viaccess PC2.4 is often referred to as Viaccess 2.
Viaccess PC2.5 is the third system to be developed. Unlike Viaccess PC2.3 and Viaccess PC2.4, Viaccess PC2.5 has not yet been broken by hackers, so it remains a secure system to this day and has since its first use years ago. Viaccess PC2.5, like Viaccess PC2.4, is often referred to as Viaccess 2.
Viaccess PC2.6 is the fourth system to be developed and used. It replaces its predecessor Viaccess PC2.5 even though it was never broken. Viaccess PC2.6 has also never been compromised since its 2005 debut, and is still in wide use. Viaccess PC2.6 is often referred to as Viaccess 3.
Viaccess PC3.0 is the latest system to be developed and in use. It is an upgrade over the previous version, Viaccess PC2.6, even though it was never compromised. Viaccess PC3.0 was launched in 2007 and to this day has remained a secure Conditional Access System.
The five Viaccess systems are in use throughout the world to protect against television piracy. Viaccess is the third largest Conditional Access System in use for digital television.