User’s Manual of IGS-20040MT
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
TLV is an acronym for
T
ype
L
ength
V
alue. A LLDP frame can contain multiple pieces of information. Each of these
pieces of information is known as TLV.
TKIP
TKIP is an acronym for
T
emporal
K
ey
I
ntegrity
P
rotocol. It used in WPA to replace WEP with a new encryption
algorithm. TKIP comprises the same encryption engine and RC4 algorithm defined for WEP. The key used for
encryption in TKIP is 128 bits and changes the key used for each packet.
U
UDP
UDP is an acronym for
U
ser
D
atagram
P
rotocol. 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.
Common network applications that use UDP include the Domain Name System (DNS), streaming media applications
such as IPTV, Voice over IP (VoIP), and Trivial File Transfer Protocol (TFTP).
UPnP
UPnP is an acronym for
U
niversal
P
lug and
P
lay. The goals of UPnP are to allow devices to connect seamlessly and to
simplify the implementation of networks in the home (data sharing, communications, and entertainment) and in
corporate environments for simplified installation of computer components
User Priority
User Priority is a 3-bit field storing the priority level for the 802.1Q frame.
V
VLAN
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