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UA - User Agent
Any device or software used to access a web page. A user agent might be a web browser, a
smart phone, or a screen reader.
UDP - User Datagram Protocol
UDP is a connectionless transport service that dispenses with the reliability services
provided by TCP. UDP gives applications a direct interface with IP and the ability to address
a particular application process running on a host via a port number without setting up a
connection session.
UI - User Interface
The part of a software application or hardware device that a user sees and interacts with.
UMTS - Universal Mobile Telecommunications Service
A GSM-based, third-generation broadband, packet-based transmission of text, digitized
voice, video and multimedia at data rates up to 2Mbps. UMTS offers a consistent set of
services to mobile users all over the world. Until UMTS is fully implemented, users can use
multi-mode devices that switch to currently available technology.
USB - Universal Serial Bus
A connection type for computing device peripherals such as a printer, mobile modem, etc.
USB Port Types
The USB ports on computers and hubs have a rectangular Type A socket, and peripheral
devices have a cable with a Type A plug. Peripherals that do not have an attached cable
have a square Type B socket on the device and a separate cable with a Type A and Type B
plug.
VPI - Virtual Path Identifier & VCI
- Virtual Channel Identifier
A VPI is a 8-bit field while VCI is a 16-bit field in the ATM cell header. A
VPI
identifies a link
formed by a virtual path and a
VCI
identifies a channel within a virtual path. In this way, the
cells belonging to the same connection can be distinguished. A unique and separate VPI/VCI
identifier is assigned in advance to indicate which type of cell is following, unassigned cells,
physical layer OAM cells, meta-signalling channel or a generic broadcast signalling channel.
Your ISP should supply you with the values.
Virtual Server
You can designate virtual servers, e.g., a FTP, web, telnet or mail server, on your local
network and make them accessible to the outside world. A virtual server means that it is
not a dedicated server -- that is, the entire computer is not dedicated to running on the
public network but in the private network.
VNC - Virtual Network Computing
A graphical desktop sharing system that uses the RFB protocol to remotely control another
computer.
VPN - Virtual Private Network
A secure private network that runs over the public Internet. Commonly used to connect to
an office network from elsewhere.
VPN Pass through
A feature that allows a client to connect to a VPN server.
WAN - Wide Area Network
A public network that extends beyond architectural, geographical, or political boundaries
(unlike a LAN, which is usually a private network located within a room, building, or other
limited area).
WCDMA - Wideband Code-Division Multiple Access
A 3G mobile wireless technology that promises much higher data speeds to mobile and
portable wireless devices. Another name for UMTS.
WEP - Wired Equivalent Privacy
An IEEE standard security protocol for 802.11 networks. Superseded by WPA and WPA2.