in data communication, a sequence of binary digits, including data and control signals, that is transmitted and switched as a composite whole. The data, control signals, and possibly error control information are arranged in a specific format, according to the communications protocol. In the TCP/IP world, packets have specific names under different protocols and different layers. At the application layer, TCP (Transmission Control Protocol) has streams and UDP (User Datagram Protocol) messages. At the transport layer, TCP has segments and UDP packets. At the Internet (network) layer are datagrams, and at the network access (data link) layer are frames.
one of the simplest and earliest forms of a firewall, a packet filter accepts or rejects traffic based on source and destination addresses, and possibly the type of traffic
string of random data, typically added to plaintext in a block cipher when the last plaintext block is short, or the original data contains long strings of null data
contraction of Web page hijacking. A masquerade attack in which the attacker copies a home page or other material from the target server, rehosts the page on a server the attacker controls, and causes the rehosted page to be indexed by the major Web search services, thereby diverting browsers from the target server to the attacker s server. This practice is infrequent, and usage of this term is rare. This term should not be confused with other forms of Web diversion.
(1) error correcting...
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