Recently, Sun and Leu proposed an efficient authentication scheme for access control in mobile pay-TV systems based on pairing and elliptic curve cryptography. In Sun and Leu's scheme, there exist two fatal security flaws, including 1) failure in subscriber authentication and 2) vulnerable to unauthorized access, which contradict to the security claims of Sun and Leu's scheme. To meet the claimed security requirements, we strengthen Sun and Leu's scheme with only lightweight modifications.
- conditional access systems
- pay-TV services