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Motivation

 

In today's Internet many applications demand security related features. In the view of new Internet services, such as video distribution or video conferencing, multicast will become an important technique to reduce network traffic. Because of the possibly large number of subscribers and the possibility for anybody to join the group, security becomes crucial for the correct behavior of multicast applications. Let's take a look at various applications and their security requirements.

• For a military secure channel we would like to have the highest secrecy (confidentiality) and authentication achievable. It also requires protection from traffic analysis.
• Commercial organizations require confidentiality and authentication for their secure communications such as video conferencing.
• Some organized chatting groups such as a virtual classroom need sender authorization to protect from malicious spamming of the group.
• An unorganized group such as non-arbitrated chatting-room may want both sender and receiver anonymity and group confidentiality.
• Commercial data/information distribution such as stock market data, weather broadcast or other database querying need sender authentication and atomicity with billing. Some receivers may want to have privacy (anonymity) too.
• Internet casinos may require customer anonymity and fairness for the game.