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SSL
Commonly used encryption scheme used by many online retail
and banking sites to protect the financial integrity of transac-
tions. When an SSL session begins, the server sends its public
key to the browser. The browser then sends a randomly gener-
ated secret key back to the server in order to have a secret key
exchange for that session
Subnetwork or
Subnet
Found in larger networks, these smaller networks are used to
simplify addressing between numerous computers. Subnets con-
nect to the central network through a router, hub or gateway.
Each individual wireless LAN will probably use the same subnet
for all the local computers it talks to.
Switch
A type of hub that efficiently controls the way multiple devices
use the same network so that each can operate at optimal per-
formance. 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.
TCP
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 down-
loaded from a web server, the TCP program layer in that server
divides the file into packets, numbers the packets, and then for-
wards 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 reassem-
bles 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 communi-
cations 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 perma-
nently 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 mul-
tiple networks (subnets) within an organization or worldwide.
VoIP
Voice transmission using Internet Protocol to create digital
packets distributed over the Internet. VoIP can be less expen-
sive than voice transmission using standard analog packets over
POTS (Plain Old Telephone Service).