AFi SM10P, Руководство пользователя

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254 Publication date: Mar., 2012
Revision A1
(Also Port Aggregation, Link Aggregation).
ARP
ARP is an acronym for Address Resolution Protocol. It is a protocol that used to convert
an IP address into a physical address, such as an Ethernet address. ARP allows a host to
communicate with other hosts when only the Internet address of its neighbors is known.
Before using IP, the host sends a broadcast ARP request containing the Internet address
of the desired destination system.
ARP Inspection
ARP Inspection is a secure feature. Several types of attacks can be launched against a
host or devices connected to Layer 2 networks by "poisoning" the ARP caches. This
feature is used to block such attacks. Only valid ARP requests and responses can go
through the switch device.
Auto-Negotiation
Auto-negotiation is the process where two different devices establish the mode of
operation and the speed settings that can be shared by those devices for a link.
C
CC
CCM
CDP
D
DEI
DES
DHCP
CC is an acronym for Continuity Check. It is a MEP functionality that is able to detect loss
of continuity in a network by transmitting CCM frames to a peer MEP.
CCM is an acronym for Continuity Check Message. It is a OAM frame transmitted from a
MEP to it's peer MEP and used to implement CC functionality.
CDP is an acronym for Cisco Discovery Protocol.
DEI is an acronym for Drop Eligible Indicator. It is a 1-bit field in the VLAN tag.
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 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