[计] 加密

[ noun ]
the activity of converting data or information into code
<noun.act>

encryption \encryption\ n.
the process of converting messages in ordinary language, or
other information into a secret coded form that cannot be
interpreted without knowing the secret method for
interpretation, called the key.

Note: Encryption is used commonly to allow messages to be
transmitted between parties at a distance without
permitting others to read and understand the message.
It is also used to make data more secure from possible
discovery and uninterpretable by unauthorized people
accessing the data. In order to read an encrypted
message, a party normally requires knowledge of both
the method of encryption and the secret key, which may
be a single word or more complex sequence of
characters. Until recently, transmission of such secret
messages required that the key be transmitted secretly
by some seecure and reliable method to the party
receiving the message. More recently, a mathematical
method was discovered to allow a party to publish an
encoding key (the public key) which allows anyone to
encode a message, but the message thus encoded can only
be decoded by the person possessing a corresponding
key, called the private key. This two-key system is
called the {public-key encryption} method.

Syn: encoding, coding, enciphering, ciphering, cyphering,
writing in code.
[WordNet 1.5]