EEye Digital Security Retina, Руководство пользователя

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Retina Users Manual Glossary
Checksum: A computed value that is dependent upon the contents of a packet. This value is sent along with the
packet when it is transmitted. The receiving system computes a new checksum based upon the received data, and
compares this value with the one sent with the packet. If the two values are the same, the receiver has a high degree
of confidence that the data was received correctly.
Circuit Switching: A communications paradigm in which a dedicated communication path is established between two
hosts, and on which all packets travel. The telephone system is an example of a circuit switched network. See also:
Connection-Oriented, Connectionless, and Packet Switching.
Client: A computer system or process that requests a service of another computer system or process. A workstation
requesting the contents of a file from a file server is a client of the file server. See also: Client-Server Model and
Server.
Client-Server Model: A common way to describe the paradigm of many network protocols. Examples include the
name-server/name-resolver relationship in DNS, and the file-server/file-client relationship in NFS. See also: Client and
Server.
Congestion: Congestion occurs when the offered load exceeds the capacity (or bandwidth) of a data communication
path.
Connection-Oriented: The data communication method in which communication proceeds through three well-
defined phases: connection establishment, data transfer, and connection release. TCP is a connection-oriented
protocol.
Connectionless:
The data communication method in which communication occurs between hosts with no previous
initialization. Packets between two hosts can take different routes, since each is independent of the other. UDP is a
connectionless protocol.
Research Networks (RARE), the CCIRN provides a forum for cooperative planning amongst the principal North
American and European research networking bodies.
Cracker: A cracker is an individual who attempts to access computer systems without authorization. These
individuals are often malicious, as opposed to hackers, and have many means at their disposal for breaking into a
system.
Cyberspace: A term coined by William Gibson in his fantasy novel Necromancer to describe the "world" of
computers, and the society that gathers around them.
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