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reassembling it at the other end. Specifically, UDP doesn't provide sequencing of the
packets that the data arrives in. This means that the application program that uses UDP
must be able to make sure that the entire message has arrived and is in the right order.
Network applications that want to save processing time because they have very small
data units to exchange (and therefore very little message reassembling to do) may
prefer UDP to TCP.
Upgrade
- To replace existing software or firmware with a newer version.
Upload
- To send a file transmitted over a network. In a communications session,
upload means transmit, and download means receive.
URL (Uniform Resource Locator)
- The address that defines the route to a file on the
Web or any other Internet facility. URLs are typed into the browser to access Web
pages, and URLs are embedded within the pages themselves to provide the hypertext
links to other pages.
UTP
- Unshielded twisted pair is the most common kind of copper telephone wiring.
Twisted pair is the ordinary copper wire that connects home and many business
computers to the telephone company. To reduce crosstalk or electromagnetic induction
between pairs of wires, two insulated copper wires are twisted around each other. Each
signal on twisted pair requires both wires. Since some telephone sets or desktop
locations require multiple connections, twisted pair is sometimes installed in two or more
pairs, all within a single cable.
VLAN (Virtual LAN)
- A logical association that allows users to communicate as if they
were physically connected to a single LAN, independent of the actual physical
configuration of the network.
Virtual Server
- Multiple servers that appear as one server, or one system image, to the
operating system or for network administration.
VPN
(Virtual Private Network) - A security measure to protect data as it leaves one
network and goes to another over the Internet.
WAN
- A communications network that covers a wide geographic area, such as a state
or country.
WEP (Wired Equivalent Privacy)
- A data privacy mechanism based on a 64-bit shared
key algorithm, as described in the IEEE 802.11 standard.
WINIPCFG
- Configuration utility based on the Win32 API for querying, defining, and
managing IP addresses within a network. A commonly used utility for configuring
networks with static IP addresses.
WLAN
(Wireless Local Area Network) - A group of computers and associated devices
that communicate with each other wirelessly.
Workgroup
- Two or more individuals that share files and databases.