Concepts inAttribute-based encryption for fine-grained access control of encrypted data

Access control

Access control refers to exerting control over who can interact with a resource. Often but not always, this involves an authority, who does the controlling. The resource can be a given building, group of buildings, or computer-based information system. But it can also refer to a restroom stall where access is controlled by using a coin to open the door. Access control is, in reality, an everyday phenomenon. A lock on a car door is essentially a form of access control.  more from Wikipedia

Encryption

In cryptography, encryption is the process of transforming information (referred to as plaintext) using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information (in cryptography, referred to as ciphertext). The reverse process, i.e. , to make the encrypted information readable again, is referred to as decryption (i.e. , to make it unencrypted).  more from Wikipedia

Broadcast encryption

Broadcast encryption is the cryptographic problem of encrypting broadcast content (e.g. TV programs) in such a way that only qualified users (e.g. subscribers who've paid their fees) can decrypt the content. The challenge arises from the requirement that unsubscription of some users should not affect the remaining users. The problem is further complicated by the fact that there is typically more than one data stream ("channel"), each of which may have a different set of subscribers.  more from Wikipedia

ID-based encryption

ID-based encryption (or identity-based encryption) is an important primitive of ID-based cryptography. As such it is a type of public-key encryption in which the public key of a user is some unique information about the identity of the user (e.g. a user's email address). This can use the text-value of the name or domain name as a key or the physical IP address it translates to.  more from Wikipedia

Cryptosystem

There are two different meanings of the word cryptosystem. One is used by the cryptographic community, while the other is the meaning understood by the public.  more from Wikipedia

Public-key cryptography

Public-key cryptography refers to a cryptographic system requiring two separate keys, one to lock or encrypt the plaintext, and one to unlock or decrypt the cyphertext. Neither key will do both functions. One of these keys is published or public and the other is kept private. If the lock/encryption key is the one published then the system enables private communication from the public to the unlocking key's owner.  more from Wikipedia