PLANET WGSD-8020 - Manual (Page 371)

User’s Manual of WGSD-8020
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responsible for ensuring that a message is divided into the packets that IP manages and for reassembling the packets
back into the complete message at the other end.
Common network applications that use TCP include the World Wide Web (WWW), e-mail, and File Transfer Protocol
(FTP).
TELNET
TELNET is an acronym for TELetype NETwork. It is a terminal emulation protocol that uses the Transmission Control
Protocol (TCP) and provides a virtual connection between TELNET server and TELNET client.
TELNET enables the client to control the server and communicate with other servers on the network. To start a Telnet
session, the client user must log in to a server by entering a valid username and password. Then, the client user can
enter commands through the Telnet program just as if they were entering commands directly on the server console.
TFTP
TFTP is an acronym for Trivial File Transfer Protocol. It is transfer protocol that uses the User Datagram Protocol (UDP)
and provides file writing and reading, but it does not provides directory service and security features.
ToS
ToS is an acronym for Type of Service. It is implemented as the IPv4 ToS priority control. It is fully decoded to
determine the priority from the 6-bit ToS field in the IP header. The most significant 6 bits of the ToS field are fully
decoded into 64 possibilities, and the singular code that results is compared against the corresponding bit in the IPv4
ToS priority control bit (0~63).
TLV
A LLDP frame can contain multiple pieces of information. Each of these pieces of information is known as TLV (TLV is
short for "Type Length Value").
U
UDP
UDP is an acronym for User Datagram Protocol. It is a communications protocol that uses the Internet Protocol (IP) to
exchange the messages between computers.
UDP is an alternative to the Transmission Control Protocol (TCP) that uses the Internet Protocol (IP). Unlike TCP, UDP
does not provide the service of dividing a message into packet datagrams, and UDP doesn't provide reassembling and
sequencing of the packets. 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 may prefer UDP to 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.