Initial viewing period for scalable authorization of streaming multimedia content

A method of multicasting comprising:

• providing program content for multicasting to a plurality of clients;
• encrypting a first portion of said program content by utilizing a first key so as to produce an encrypted first portion of said program content;
• providing said plurality of clients with said first key;
• multicasting said encrypted first portion of said program content to said plurality of clients prior to said plurality of clients indicating an intent to purchase said program content.

A method comprising:

• providing program content for multicasting;
• multicasting a first portion of said program content to a plurality of clients at no charge;
• providing a guaranteed time period during multicasting of said first portion of said program content;
• estimating a number of clients that will purchase said program content during said guaranteed time period;
• receiving orders for said program content from at least one purchasing client during said guaranteed time period;
• providing an initial key distribution period having a duration operable to provide cryptographic keys to said at least one purchasing client so as to allow reception of said program content not to be interrupted at said at least one purchasing client.

A method of multicasting program content, said method comprising:

• providing program content for distribution to a plurality of clients;
• providing a first time period for purchasing an uninterrupted viewing of said program content;
• receiving a purchase request from a purchasing client for said program content;
• providing a second time period for purchasing said program content, said second time period occurring after said first time period;
• receiving a purchase request from a late purchasing client for said program content during said second time period;
• delaying decryption of said program content at said late purchasing client until said program content can be decrypted at said late purchasing client without interrupting presentation of said program content at said late purchasing client.

A computer-readable medium having computer-executable code for performing a method comprising:

• providing a first key to a group of said plurality of clients;
• providing a second key for use in decrypting a first portion of said program content;
• providing said second key to at least one client of said plurality of clients;
• utilizing said second key at a server to encrypt said first portion of said program content so as to create an encrypted first portion of said program content;
• multicasting said encrypted first portion of said program content to said group of said plurality of clients;
• permitting said at least one client to decrypt said encrypted first portion of said program content with said second key.

A computer-readable medium having computer-executable code for performing a method comprising:

• providing program content for multicasting to a plurality of clients;
• encrypting a first portion of said program content by utilizing a first key so as to produce an encrypted first portion of said program content;
• providing said plurality of clients with said first key;
• multicasting said encrypted first portion of said program content to said plurality of clients prior to said plurality of clients indicating an intent to purchase said program content.

A computer-readable medium having computer-executable code for performing a method comprising:

• providing program content for multicasting;
• multicasting a first portion of said program content to a plurality of clients at no charge;
• providing a guaranteed time period during multicasting of said first portion of said program content;
• estimating a number of clients that will purchase said program content during said guaranteed time period;
• receiving orders for said program content from at least one purchasing client during said guaranteed time period;
• providing an initial key distribution period having a duration operable to provide cryptographic keys to said at least one purchasing client so as to allow reception of said program content not to be interrupted at said at least one purchasing client.

A computer-readable medium having computer-executable instructions for performing a method comprising:

• providing program content for distribution to a plurality of clients;
• providing a first time period for purchasing an uninterrupted viewing of said program content;
• receiving a purchase request from a purchasing client for said program content;
• providing a second time period for purchasing said program content, said second time period occurring after said first time period;
• receiving a purchase request from a late purchasing client for said program content during said second time period;
• delaying decryption of said program content at said late purchasing client until said program content can be decrypted at said late purchasing client without interrupting presentation of said program content at said late purchasing client.