Technical data

© 2012 Meru Networks, Inc. Glossary 339
switch
A type of hub that efficiently controls the way multiple devices use the same network so
that each can operate at optimal performance. A switch acts as a networks traffic cop:
rather than transmitting all the packets it receives to all ports as a hub does, a switch
transmits packets to only the receiving port.
T
TCP
Transmission Control Protocol. A protocol used along with the Internet Protocol (IP) to send
data in the form of individual units (called packets) between computers over the Internet.
While IP takes care of handling the actual delivery of the data, TCP takes care of keeping
track of the packets that a message is divided into for efficient routing through the
Internet. For example, when a web page is downloaded from a web server, the TCP
program layer in that server divides the file into packets, numbers the packets, and then
forwards them individually to the IP program layer. Although each packet has the same
destination IP address, it may get routed differently through the network. At the other
end, TCP reassembles the individual packets and waits until they have all arrived to
forward them as a single file.
TCP/IP
The underlying technology behind the Internet and communications between computers in
a network. The first part, TCP, is the transport part, which matches the size of the
messages on either end and guarantees that the correct message has been received. The
IP part is the user's computer address on a network. Every computer in a TCP/IP network
has its own IP address that is either dynamically assigned at startup or permanently
assigned. All TCP/IP messages contain the address of the destination network as well as
the address of the destination station. This enables TCP/IP messages to be transmitted to
multiple networks (subnets) within an organization or worldwide.
TKIP
Temporal Key Integrity Protocol. An enhancement to the WEP encryption technique that
uses a set of algorithms to rotate session keys for better protection. TKIP uses RC4
ciphering, but adds functions such as a 128-bit encryption key, a 48-bit initialization
vector, a new message integrity code (MIC), and initialization vector (IV) sequencing rules.
U
USB
A high-speed bidirectional serial connection between a PC and a peripheral that transmits
data at the rate of 12 megabits per second. The new USB 2.0 specification provides a data
rate of up to 480 Mbps, compared to standard USB at only 12 Mbps. 1394, FireWire and
iLink all provide a bandwidth of up to 400 Mbps.
UTC
Universal Time Coordinated. Also known as Greenwich Mean Time. The time is not adjusted
for time zones or for daylight savings time.
V
Virtual Cell
Proprietary wireless LAN architecture in which multiple access points are pooled into a
single, virtual resource. To the client, APs are indistinguishable because they all use the
same BSSID and radio channel . Because clients remain connected to the same virtual AP
as they move through a network, no client-initiated handoffs are necessary. Instead, the