User guide

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Parameter values supported include NONE or ESP.

encryption. The application of a speciﬁc algorithm to a data

set so that anyone without the encryption key cannot under-

stand the information.

ESP. Encapsulation Security Payload (ESP) header provides

conﬁdentiality, data origin authentication, connectionless integ-

rity, anti-replay protection, and limited trafﬁc ﬂow conﬁdentiality.

It encrypts the contents of the datagram as speciﬁed by the

Security Association. The ESP transformations encrypt and

decrypt portions of datagrams, wrapping or unwrapping the dat-

agram within another IP datagram. Optionally, ESP transforma-

tions may perform data integrity validation and compute an

Integrity Check Value for the datagram being sent. The com-

plete IP datagram is enclosed within the ESP payload.

Ethernet crossover cable. See crossover cable.

-----F-----

FCS. Frame Check Sequence. Data included in frames for error

control.

ﬂow control. Technique using hardware circuits or control char-

acters to regulate the transmission of data between a computer

(or other DTE) and a modem (or other DCE). Typically, the

modem has buffers to hold data; if the buffers approach capac-

ity, the modem signals the computer to stop while it catches up

on processing the data in the buffer. See CTS, RTS, xon/xoff.

fragmentation. Process of breaking a packet into smaller units

so that they can be sent over a network medium that cannot

transmit the complete packet as a unit.