This article introduces the MUDS function in rural cable television development,it emphasizes the character of MUDS system which is made up of five parts: the centre of the digital television,the connecting station,the transmitter station of the digital MUDS,the direct broadcast station of the digital MUDS and the receiving system of the users.

SQL injection is a type of script attack,both the principle and general step of SQL injection are elaborated comprehensively in the paper,unified certain special details,blind SQL Injection,Cross Site Scripting,crack examination and how to keep away from SQL injection are also discussed.

Implementation of EPON upstream access;