Digitus DN-80233, Руководство пользователя

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Command Line Interface.
CLI is a line-item interface for configuring systems. (In the case of our switch,
it is one of the user interfaces they have programmed for allowing programmers to configure their
system).
Common Open Policy Service Protocol.
A proposed standard protocol for exchanging network
policy information between a Policy Decision Point (PDP) in a network and Policy Enforcement Points
(PEPs) as part of overall Quality of Service (QoS) - the allocation of network traffic resources according to
desired priorities of service. The policy decision point might be a network server controlled directly by the
network administrator who enters policy statements about which kinds of traffic (voice, bulk data, video,
teleconferencing, and so forth) should get the highest priority. The policy enforcement points might be
router or layer 3 switches that implement the policy choices as traffic moves through the network.
Currently, COPS is designed for use with the Resource Reservation Protocol (RSVP), which lets you
allocate traffic priorities in advance for temporary high-bandwidth requirements (for example, video
broadcasts or multicasts). It is possible that COPS will be extended to be a general policy
communications protocol.
Complex Programmable Logic Device.
CPLD is a programmable circuit on which a logic network
can be programmed after its construction.
COPS.
See “Common Open Policy Service Protocol.” on page 295.
CPLD.
See “Complex Programmable Logic Device.” on page 295.
D
DAPI.
See “Device Application Programming Interface” on page 295.
Device Application Programming Interface.
DAPI is the software interface that facilitates
communication of both data and control information between the Application Layer and HAPI, with
support from System Support.
DHCP.
See “Dynamic Host Configuration Protocol.” on page 296.
Differentiated Services.
Diffserv is a protocol for specifying and controlling network traffic by class so
that certain types of traffic get precedence - for example, voice traffic, which requires a relatively
uninterrupted flow of data, might get precedence over other kinds of traffic. Differentiated Services is the
most advanced method for managing traffic in terms of what is called Class of Service (CoS). Unlike the
earlier mechanisms of 802.1P tagging and Type of Service (ToS), Differentiated Services avoids simple
priority tagging and depends on more complex policy or rule statements to determine how to forward a
given network packet. An analogy is made to travel services, in which a person can choose among
different modes of travel - train, bus, airplane - degree of comfort, the number of stops on the route,
standby status, the time of day or period of year for the trip, and so forth. For a given set of packet travel
rules, a packet is given one of 64 possible forwarding behaviors - known as per hop behaviors (PHBs). A
six-bit field, known as the Differentiated Services Code Point (DSCP), in the Internet Protocol (Internet
Protocol) header specifies the per hop behavior for a given flow of packets. Differentiated Services and
the Class of Service approach provide a way to control traffic that is both more flexible and more
scalability than the Quality of Service approach.
Diffserv.
See “Differentiated Services.” on page 296..
Distance-Vector Multicast Routing Protocol.
DVMRP is a distance vector routing protocol used
between routers in an intranet. This hop-based protocol describes a method of building multicast trees
from the multicast source to all the receivers (or leaves) of the tree.
DVMRP.
See “Distance-Vector Multicast Routing Protocol.” on page 296.
Dynamic Host Configuration Protocol.
DHCP is a protocol for assigning dynamic IP addresses to
devices on a network. With dynamic addressing, a device can have a different IP address every time it
connects to the network. In some systems, the device's IP address can even change while it is still
connected. DHCP also supports a mix of static and dynamic IP addresses. Dynamic addressing simplifies