D-Link AirPremier DWL-2210AP Manual page 176

Glossary
Multicast
A Multicast sends the same message to a select group of recipients. Sending an e-mail message
to a mailing list is an example of multicasting. In wireless networks, multicast usually refers to an
interaction in which the access point sends data traffic in the form of
specified set of client stations
Some wireless security modes distinguish between how unicast, multicast, and broadcast frames
are encrypted or whether they are encrypted. See also
NAT
Network Address Translation is an Internet standard that masks the internal IP addresses being
used in a LAN. A NAT server running on a gateway maintains a translation table that maps all
internal IP addresses in outbound requests to its own address and converts all inbound requests
to the correct internal host.
NAT serves three main purposes: it provides security by obscurity by hiding internal IP addresses,
enables the use of a wide range of internal IP addresses without fear of conflict with the addresses
used by other organizations, and it allows the use of a single Internet connection.
Network Address
See IP Address.
NIC
A Network Interface Card is an adapter or expansion board inserted into a computer to provide
a physical connection to a network. Most NICs are designed for a particular type of network,
protocol, and media, for example,
NTP
The Network Time Protocol assures accurate synchronization of the system clocks in a network
of computers. NTP servers transmit Coordinated Universal Time (UTC, also known as Greenwich
Mean Time) to their client systems. An NTP client sends periodic time requests to servers, using
the returned time stamp to adjust its clock.
OSI
The Open Systems Interconnection (OSI) reference model is a framework for network design.
The OSI model consists of seven layers:
• Layer 1, the Physical layer, identifies the physical medium used for communication between
nodes. In the case of wireless networks, the physical medium is air, and radio frequency (RF)
waves are a components of the physical layer.
• Layer 2, the Data-Link layer, defines how data for transmission will be structured and formatted,
along with low-level protocols for communication and addressing. For example, protocols such
as CSMA/CA and components like
as a part of the Data-Link layer.
(MAC addresses) on the network.
Ethernet or wireless.
MAC addresses, and Frames are all defined and dealt with
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IEEE 802.1x
Unicast and Broadcast.
Frames to a