Edge-Core Direk Tronik 24/48-Port, Руководство по управлению

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Glossary-1
Glossary
Access Control List (ACL)
ACLs can limit network traffic and restrict access to certain users or devices by
checking each packet for certain IP or MAC (i.e., Layer 2) information.
Boot Protocol (BOOTP)
BOOTP is
used to provide bootup information for network devices, including IP
address information, the address of the TFTP server that contains the devices
system files, and the name of the boot file.
Class of Service (CoS)
CoS is supported by prioritizing packets based on the required level of service, and
then placing them in the appropriate output queue. Data is transmitted from the
queues using weighted round-robin service to enforce priority service and prevent
blockage of lower-level queues. Priority may be set according to the port default, the
packet’s priority bit (in the VLAN tag), TCP/UDP port number, IP Precedence bit, or
DSCP priority bit.
Differentiated Services (DiffServ)
DiffServ
provides quality of service on large networks by employing a well-defined
set of building blocks from which a variety of aggregate forwarding behaviors may
be built. Each packet carries information (DS byte) used by each hop to give it a
particular forwarding treatment, or per-hop behavior, at each network node.
DiffServ
allocates different levels of service to users on the network with mechanisms such
as traffic meters, shapers/droppers, packet markers at the boundaries of the
network.
Differentiated Services Code Point Service (DSCP)
DSCP uses a six-bit tag to provide for up to 64 different forwarding behaviors. Based
on network policies, different kinds of traffic can be marked for different kinds of
forwarding. The DSCP bits are mapped to the Class of Service categories, and then
into the output queues.
Domain Name Service (DNS)
A system used for translating host names for network nodes into IP addresses.
Dynamic Host Control Protocol (DHCP)
Provides a framework for passing configuration information to hosts on a TCP/IP
network. DHCP is based on the Bootstrap Protocol (BOOTP), adding the capability
of automatic allocation of reusable network addresses and additional configuration
options.