EEye Digital Security Retina, Руководство пользователя

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Retina Users Manual Glossary
PING: Packet Internet Groper. A program used to test reach ability of destinations by sending them an ICMP echo
request and waiting for a reply.
Point Of Presence (POP): A site where there exists a collection of telecommunications equipment, usually digital
leased lines and multi-protocol routers.
Point-to-Point Protocol (PPP): The Point-to-Point Protocol, defined in RFC 1171, provides a method for transmitting
packets over serial point-to-point links. See also: Serial Line IP.
POP: See: Post Office Protocol and Point Of Presence
Port: A port in the network sense is the pathway that a computer uses to transmit and receive data.
Post Office Protocol (POP): A protocol designed to allow single user hosts to read mail from a server. There are
three versions: POP, POP2, and POP3. Latter versions are NOT compatible with earlier versions. See also: Email.
Postmaster: The person responsible for taking care of email problems, answering queries about users, and other
related work at a site.
PPP: See: Point-to-Point Protocol
Privacy Enhanced Mail (PEM): Internet email that provides confidentiality, authentication and message integrity
using various encryption methods.
Protocol: A formal description of message formats and the rules two computers must follow to exchange those
messages. Protocols can describe low-level details of machine-to-machine interfaces (e.g., the order in which bits and
bytes are sent across a wire) or high-level exchanges between allocation programs (e.g., the way in which two
programs transfer a file across the Internet).
Protocol Converter: A device/program that translates between different protocols that serve similar functions (e.g.,
TCP and TP4).
Protocol Stack: A layered set of protocols that work together to provide a set of network functions. See also: Layer
and Protocol.
Proxy ARP: The technique in which one machine, usually a router, answers ARP requests intended for another
machine. By "faking" its identity, the router accepts responsibility for routing packets to the "real" destination. Proxy
ARP allows a site to use a single IP address with two physical networks. See also: Address Resolution Protocol
PSN: See: Packet Switch Node.
Q
Queue: A backlog of packets or connections awaiting processing.
R
RARP: Reverse Address Resolution Protocol. A protocol, defined in RFC 903, which provides the reverse function of
ARP. RARP maps a hardware (MAC) address to an Internet address.
Diskless nodes primarily use RARP when they first initialize to find their Internet address. See also: Address
Resolution Protocol, BOOTP, Internet Address, and MAC Address.
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