Vigitron MaxiiNet Vi30126 Series, Руководство по эксплуатации

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CCM
CCM is an acronym for Continuity Check Message. It is an OAM frame
transmitted from a MEP to its peer MEP and used to implement CC functionality.
CDP
CDP is an acronym for Cisco Discovery Protocol.
D
DEI
DEI is an acronym for Drop Eligible Indicator. It is a 1-bit field in the VLAN tag.
DES
DES is an acronym for Data Encryption Standard. 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 Dynamic Host Configuration Protocol. It is a protocol
used for assigning dynamic IP addresses to devices on a network.
DHCP used by networked computers (clients) to obtain IP addresses and other
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 assignment is valid
(its lease has not expired). Therefore, IP address pool management is done by
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 added to a network without the
hassle of manually assigning it a unique IP address.
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.