USRobotics Instant802 APSDK - Manual (Page 320)

Professional Access Point
Administrator Guide
Glossary - 320
U
UDP
The User Datagram Protocol (UDP) is a transport layer protocol providing simple but unreliable datagram
services. It adds port address information and a checksum to an
IP packet.
UDP neither guarantees delivery nor does it require a connection. It is lightweight and efficient. All error
processing and retransmission must be performed by the application program.
Unicast
A Unicast sends a message to a single, specified receiver. In wireless networks, unicast usually refers to
an interaction in which the access point sends data traffic in the form of
IEEE 802.1x Frame s directly to a
single client station MAC address on the network.
Some wireless security modes distinguish between how unicast, multicast, and broadcast frames are
encrypted or whether they are encrypted.
See also Multicast and Broadcast .
URL
A Uniform Resource Locator (URL) is a standard for specifying the location of objects on the Internet, such
as a file or a newsgroup. URLs are used extensively in HTML documents to specify the target of a
hyperlink which is often another HTML document (possibly stored on another computer). The first part of
the URL indicates what protocol to use and the second part specifies the IP address or the domain name
where that resource is located.
For example, ftp://ftp.usr.com/downloads/myfile.tar.gz specifies a file that should be fetched
using the FTP protocol; http://www.usr.com/index.html specifies a Web page that should be fetched
using the HTTP protocol.
V
VLAN
A virtual LAN (VLAN) is a software-based, logical grouping of devices on a network that allow them to act
as if they are connected to a single physical network, even though they may not be. The nodes in a VLAN
share resources and bandwidth, and are isolated on that network. The Professional Access Point supports
the configuration of a wireless VLAN. This technology is used on the access point for the virtual guest
network feature.
VPN
A Virtual Private Network (VPN) is a network that uses the Internet to connect its nodes. It uses encryption
and other mechanisms to ensure that only authorized users can access its nodes and that data cannot be
intercepted.