Demanding a video program by using demand short message

A Video-on-Demand system for demanding a video program via a short message, comprising:

• short message generating means for receiving a user demand, and generating a demand short message based on the user demand, said demand short message including at least a User Identifier field, a Program Identifier field of the demanded video program and an Authentication field;
• short message sending means for sending the demand short message generated by the short message generating means;
• demand short message processing means at a program delivering end for receiving the demand short message, processing the received demand short message to extract the user identifier and using the Authentication field to authenticate the legality of the user, and sending the program identifier of the demanded program by a legal user to video delivering means;
• video delivering means for sending program content corresponding to the program identifier from the program delivering end to the user end indicated by a legal user identifier;
• and
• program playing means at the user end for receiving the video program sent by the video delivering means and playing it back to the user.

Short message generating means in a Video-on-Demand system, comprising:

• a receiving unit for receiving a user demand;
• a program information generating unit for generating, according to the user demand, program information including at least a User Identifier field and a Program Identifier field of the demanded video program;
• an Authentication field generating unit for generating a Authentication field according to the program information generated by the program information generating unit;
• and
• an output unit for outputting said program information and the Authentication field as a demand short message to short message sending means.

A short message generating method in a Video-on-Demand system, comprising the steps of:

• receiving a user demand;
• generating, according to the user demand, program information including at least a User Identifier field and a Program Identifier field of a demanded video program;
• generating an Authentication field according to the generated program information;
• and
• outputting said program information and the Authentication field as a demand short message to short message sending means.

Demand short message processing means in a Video-on-Demand system, comprising:

• a receiving unit for receiving a demand short message;
• an extracting unit for extracting a user identifier from the demand short message received by the receiving unit;
• an authentication unit for authenticating legality of a user identified by the user identifier extracted by the extracting unit, according to the Authentication field in the demand short message received by the receiving unit;
• and
• an outputting unit for outputting a program identifier of the program which the legal user demands.

A demand short message processing method in a Video-on-Demand system, comprising the steps of:

• receiving a demand short message;
• extracting a user identifier from the received demand short message;
• authenticating legality of a user identified by the extracted user identifier, according to the Authentication field in the received demand short message;
• and
• outputting a program identifier of the program which the legal user demands.