The thesis presents another form of techniques that can be used to encrypt DVB stream by using block cipher system and stream cipher system. The proposed systems for block cipher are the well known Blowfish and the Advanced Encryption Standard. These block ciphers have great advantages over other forms of block ciphers in now a days furthermore stream cipher that suffer from key Length and key distribution for high security. The thesis suggests the use of gold sequence in the security. This will improve the system because it has excellent randomness and long key space such that the break of such technique is difficult. The DVB-S has been simulate using recent version of MATLAB (ver.7) together with three proposed security systems. Computer test have been carried out to evaluate these systems over the DVB-S from the compatibility point of view. The results show that the three systems operate well with DVB-S and the best recommended one is the AES the best between delay and security.