2

What is the exact difference between attribute-based encryption (ABE) and attribute-based broadcast encryption (ABBE)? Is ABBE equivalent to broadcast encryption on top of ABE?

akshu281
  • 23
  • 2

1 Answers1

2

At first, the abbreviation “ABBE” is used by Zhou et al. in [2] as a name for his ABE scheme. Zhou builds on top of a CP-ABE scheme which in addition supports “constant” ciphertexts (named CCP-ABE). From this perspective ABBE is a specific ABE scheme based on CP-ABE supporting constant ciphertexts.

However, in a more general way, I see ABE in the context of Broadcast communication as:

A merge ofthe notion of ABE and Broadcast Encryption. Broadcast related use-cases have special requirements which you have to take into consideration not only when applying ABE.

There are broadcast-enabled ABE schemes which build on top of KP-ABE[1,3] or CP-ABE[1,2,2a]. More or less broadcast-enabled ABE schemes face the same challanges and thus focus on similar properties/aspects.

Some often recurring aspects in ABE-based broadcast scenarios are:

  • Size of the ciphertext: a constant message size is often advantage. In addition the message size itself is of interest.

  • Access Structure: The ciphertext size depends on the embedded access structure. The access structure is important not only when thinking about how to enforce revocation.

  • General communication and storage overheads are more of importance in Broadcast scenarios - compare [2a].

[1] Attrapadung et al., 2009: Conjunctive Broadcast and Attribute-Based Encryption.

[2] Zhou et al., 2010: On Efficient Ciphertext-Policy Attribute Based Encryption and Broadcast Encryption, Source: http://eprint.iacr.org/2010/395

[2a] Zhou et al.2015: Efficient Privacy-Preserving Ciphertext-Policy Attribute Based Encryption and Broadcast Encryption

[3] Sun et al., 2013: A Key-Policy Attribute-based Broadcast Encryption.