19216811.live181
TCP
The
Transmission Control Protocol
(TCP) is built on top of Internet Protocol (
IP
). It adds
reliable communication (guarantees delivery of data), flow-control, multiplexing (more than one
simultaneous connection), and connection-oriented transmission (requires the receiver of a
packet to acknowledge receipt to the sender). It also guarantees that packets will be delivered in
the same order in which they were sent.
TCP/IP
The Internet and most local area networks are defined by a group of protocols. The most important
of these is the
Transmission Control Protocol over Internet Protocol
(TCP/IP), the de facto standard
protocols. TCP/IP was originally developed by Defense Advanced Research Projects Agency
(DARPA, also known as ARPA, an agency of the US Department of Defense).
Although
TCP
and
IP
are two specific protocols, TCP/IP is often used to refer to the entire protocol
suite based upon these, including ICMP, ARP,
UDP
, and others, as well as applications that run
upon these protocols, such as telnet, FTP, etc.
TKIP
The
Temporal Key Integrity Protocol
(TKIP) provides an extended 48-bit initialization vector,
per-packet key construction and distribution, a Message Integrity Code (MIC, sometimes called
“Michael”), and a re-keying mechanism. It uses a
RC4
stream cipher to encrypt the frame body
and CRC of each
802.11
frame before transmission. It is an important component of the
WPA
and
802.11i
security mechanisms.
ToS
TCP/IP
packet headers include a 3-to-5 bit Type
of Service
(ToS) field set by the application
developer that indicates the appropriate type of service for the data in the packet. The way the
bits are set determines whether the packet is queued for sending with minimum delay, maximum
throughput, low cost, or midway “best-effort” settings depending upon the requirements of the data.
The ToS field is used by the D-Link DWL-2210AP to provide configuration control over
Quality of
Service
(
QoS
) queues for data transmitted from the AP to client stations.
UDP
The
User Datagram Protocol
(UDP) is a transport layer protocol providing simple but unreliable
datagram services. It adds port address information and a checksum to an
IP
packet. UDP
neither guarantees delivery nor does it require a connection. It is lightweight and efficient. All error
processing and retransmission must be performed by the application program.
Unicast
A
Unicast
sends a message to a single, specified receiver. In wireless networks, unicast usually
refers to an interaction in which the access point sends data traffic in the form of
IEEE 802.1x
Frame
s directly to a single client station
MAC
address on the network.
Some wireless security modes distinguish between how unicast, multicast, and broadcast frames
are encrypted or whether they are encrypted.
See also
Multicast
and
Broadcast
.
Glossary