User`s guide

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Trivial File Transfer Protocol (TFTP)
An Internet software utility for transferring files that is simpler to use than the File Transfer
Protocol (FTP) but less capable. It is used where user authentication and directory visibility are
not required. TFTP uses the User Datagram Protocol (UDP) rather than the Transmission
Control Protocol (TCP). TFTP is described formally in Request for Comments (RFC) 1350.
TTY port redirection
The process of establishing a connection between the host and networked serial devices by
creating a local TTY port on the host.
The TTY port appears and behaves as a local port
to the PC or server. See also RealPort
TXD
Transmit eXchange Data.
User Datagram Protocol (UDP)
A communications protocol that offers a limited amount of service when messages are
exchanged between computers in a network that uses the Internet Protocol (IP). UDP is an
alternative to the Transmission Control Protocol (TCP) and, together with IP, is sometimes
referred to as UDP/IP. Like TCP, UDP uses the Internet Protocol to actually get a data unit
(called a datagram) from one computer to another. Unlike TCP, however, UDP does not provide
the service of dividing a message into packets (datagrams) and reassembling it at the other end.
Specifically, UDP does not provide sequencing of the packets in which the data arrives, nor does
it guarantee delivery of data. 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. The
Trivial File Transfer Protocol (TFTP) uses UDP instead of TCP. UDP provides two services not
provided by the IP layer. It provides port numbers to help distinguish different user requests and,
optionally, a checksum capability to verify that the data arrived intact. In the Open Systems
Interconnection (OSI) communication model, UDP, like TCP, is in layer 4, the Transport Layer.
web interface
The web-based interface for configuring, monitoring, and administering Digi devices.
WEP
See Wired Equivalent Privacy.
Wired Equivalent Privacy (WEP)
A data encryption method used to protect the transmission between 802.11 wireless clients and
access points. See also Temporal Key Integrity Protocol (TKIP).
Wi-Fi Protected Access (WPA)
A data encryption/ user authentication method for 802.11 wireless LANs. WPA uses the
Temporal Key Integrity Protocol (TKIP).
WPA
See Wi-Fi Protected Access.
WPA2/802.11i
WPA with AES-based encryption (CCMP)