Broadcast Encryption

A broadcast encryption scheme allows the sender to securely distribute data to a dynamically changing set of users over an insecure channel. One of the most challenging settings for this problem is that of stateless receivers, where each user is given a fixed set of keys which cannot be updated through the lifetime of the system. This setting was considered by Naor, Naor and Lotspiech [17], who also present a very efficient “subset difference” (SD) method for solving this problem. The efficiency of this method was recently improved by Halevi and Shamir [12], who called their refinement the “Layered SD” (LSD) method. Both of the above methods were originally designed to work in the symmetric key setting, where only the trusted designer of the system can encrypt messages to users. On the other hand, in many applications it is desirable not to store the secret keys “on-line”, or to allow untrusted users to broadcast information. This leads to the question of building a publ...

• Type: Conference
• Year: 1993
• Where: CRYPTO
• Authors: Amos Fiat, Moni Naor
• Keywords: Broadcast Encryption Scheme, CRYPTO 1993, Cryptology, Key Setting, Public Key