D
DEI
DEI is an acronym for
D
rop
E
ligible
I
ndicator. It is a 1-bit field in the VLAN tag.
DES
DES is an acronym for
D
ata
E
ncryption
S
tandard. It provides a complete
description of a mathematical algorithm for encrypting (enciphering) and
decrypting (deciphering) binary coded information.
Encrypting data converts it to an unintelligible form called cipher. Decrypting
cipher converts the data back to its original form called plaintext. The algorithm
described in this standard specifies both enciphering and deciphering operations
which are based on a binary number called a key.
DHCP
DHCP is an acronym for
D
ynamic
H
ost
C
onfiguration
P
rotocol. It is a protocol
used for assigning dynamic IP addresses to devices on a network.
used by networked computers (clients) to obtain IP addresses and other
ment is valid
(its lease has not expired). Therefore, IP address pool management is done by
ed to a network without the
ssigning it a unique IP address.
DHCP
parameters such as the default gateway, subnet mask, and IP addresses
of DNS servers from a DHCP server.
The DHCP server ensures that all IP addresses are unique, for example, no IP
address is assigned to a second client while the first client's assign
the server and not by a human network administrator.
Dynamic addressing simplifies network administration because the software
keeps track of IP addresses rather than requiring an administrator to manage the
task. This means that a new computer can be add
hassle of manually a
DHCP Relay
DHCP Relay is used to forward and to transfer DHCP messages between the
clients and the server when they are not on the same subnet domain.
HCP option 82 enables a DHCP relay agent to insert specific information
nt DHCP packets to a DHCP
server and remove the specific information from a DHCP reply packets when
forwarding server DHCP packets to a DHCP client. The DHCP server can use this
information to implement IP address or other assignment policies. Specifically the
option works by setting two sub-options: Circuit ID (option 1) and Remote ID
(option2). The Circuit ID sub-option is supposed to include information specific to
which circuit the request came in on. The Remote ID sub-option was designed to
The D
into a DHCP request packets when forwarding clie
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Summary of Contents for GV-POE0812
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