D-Link DES-3226L, Справочник команд интерфейса командной строки

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126 D-Link DES-3226L Command Line Reference
Multiplexing. A function within a layer that interleaves
the information from multiple connections into one
connection.
MUX. See “Multiplexing” on page 126.
N
NAT. See “Network Address Translation” on page 126.
Network Address Translation. Sometimes referred to as
Transparent Proxying, IP Address Overloading, or IP
Masquerading. Involves use of a device called a Network
Address Translator, which assigns a contrived, or logical,
IP address and port number to each node on an
organization's internal network and passes packets using
these assigned addresses.
Network Layer Reachability Information. Information
that is carried in BGP packets which reveals the IP
addresses of the destination systems.
NLRI. Network Layer Reachability Information
NM. Network Module.
nm. Nanometer (1 x 10e
9
) meters.
NP. Network Processor.
O
Open Systems Interconnection. OSI is a seven (7) layer
architecture model for communications systems developed
by the ISO for the interconnection of data communications
systems. Each layer uses and builds on the services
provided by those below it.
Operating System Application Programming
Interface.
OSAPI is a module within the System Support
software that provides a set of interfaces to OS support
functions.
OS. Operating System.
OSAPI. See “Operating System Application
Programming Interface” on page 126.
OSI. See “Open Systems Interconnection” on page 126.
P
PDU. See “Protocol Data Unit” on page 126.
PMC. Packet Mode Channel.
Port Mirroring. Also known as a roving analysis port.
This is a method of monitoring network traffic that
forwards a copy of each incoming and outgoing packet
from one port of a network switch to another port where
the packet can be studied. A network administrator uses
port mirroring as a diagnostic tool or debugging feature,
especially when fending off an attack. It enables the
administrator to keep close track of switch performance
and alter it if necessary. Port mirroring can be managed
locally or remotely. An administrator configures port
mirroring by assigning a port from which to copy all
packets and another port where those packets will be sent.
A packet bound for or heading away from the first port
will be forwarded onto the second port as well. The
administrator places a protocol analyzer on the port
receiving the mirrored data to monitor each segment
separately. The analyzer captures and evaluates the data
without affecting the client on the original port. The
monitor port may be a port on the same SwitchModule
with an attached RMON probe, a port on a different
SwitchModule in the same hub, or the SwitchModule
processor. Port mirroring can consume significant CPU
resources while active. Better choices for long-term
monitoring may include a passive tap like an optical probe
or an Ethernet repeater.
Protocol Data Unit. PDU is a packet of data passed
across a network. The term implies a specific layer of the
OSI model and a specific protocol.
Q
QoS. See “Quality of Service” on page 126.
Quality of Service. QoS is a networking term that
specifies a guaranteed level of throughput. Throughput is
the amount of data transferred from one device to another
or processed in a specified amount of time - typically,
throughputs are measured in bytes per second (Bps).
R
Real-Time Operating System. RTOS is a component of
the OSAPI module that abstracts operating systems with
which other systems can interface.
RFC. Request For Comment.
RMON. Short for remote monitoring, a network
management protocol that allows network information to
be gathered at a single workstation. Whereas SNMP
gathers network data from a single type of Management
Information Base (MIB), RMON 1 defines nine additional
MIBs that provide a much richer set of data about network
usage. For RMON to work, network devices, such as hubs
and switches, must be designed to support it. The newest
version of RMON, RMON 2, provides data about traffic at