AddPac IPNext190 Installation Manual page 128

IPNext 190 System Installation Guide
LAN
Link
Loopback Test
MAC Address
MAN
MGCP
NAT
NTP
Stands for Local Area Network. This is a low-error, high-speed data network that covers
relatively small geographical areas of up to several thousand meters. LAN inter-connects
workstations, peripherals, terminals, and other devices in a building or a geographically
limited area. The LAN standard specifies a cable connection and signal processing method
in the physical layer and data link layer of the OSI model. Reference: MAN, WAN.
This is a network communication channel configured with lines or a transmission path
between the transmitter and receiver and related devices. A link mainly refers to WAN
connections, and is sometimes called a line or a transmission link.
This test is performed as follows: Transmit a signal or return it to the transmitter at a
location on the communication path. This loopback test is usually performed to test the
availability of network interfaces.
Stands for Media Access Control Address. This is a standard data link layer address
required for any and all ports and devices connected to LAN. Other devices on a network
use this address to locate a specific port within the network and to create or update a
routing table and data structure. A MAC address is 6 bytes long, and is managed by IEEE.
A MAC address is called as a hardware address, a MAC-layer address, or a physical
address. Compare to: Network Address
Stands for Metropolitan-Area Network. This network covers the entire area of a large city.
The operation area of MAN is geographically larger than that of LAN; however, is smaller
than that of WAN. Compare to: LAN, WAN.
MGCP, which is also known as H.248 or Megaco, is a standard protocol required to operate
signals required during a multimedia conference or to manage sessions. This protocol
defines a method of communications between the media gateway that converts the data
format required for a circuit switching network to the one required for a packet switching
network and the media gateway control device. MGCP may be used to set up, manage, and
complete calls among multiple endpoints. Megaco and H.248 are the improved version of
MGCP.
Stands for Network Address Translation. NAT is a mechanism for reducing the need for
globally unique IP addresses. NAT allows you to access the Internet as an organization
whose address is not globally unique converts the address to an address space where the
address can be globally routed. NAT is also called Network Address Translator.
Stands for Network Time Protocol. NTP, which is built based on TCP, sets a local time
accurately based on a wireless clock and an atomic clock on the Internet. NTP can
synchronize a distributed clock in the unit of milliseconds for a long time.
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