Chapter 1. Before You Start
Air Live IAS-2000 User’s Manual V1.0
.
12
SSL
Secure Sockets Layer. Commonly used encryption scheme used by many online retail and banking sites to protect
the financial integrity of transactions. When an SSL session begins, the server sends its public key to the browser.
The browser then sends a randomly generated secret key back to the server in order to have a secret key exchange
for that session.
Static IP Address
A fixed address assigned to a computer or device that is connected to a network.
Subnet Mask
An address code that determines the size of the network.
Subnetwork or Subnet
Found in larger networks, these smaller networks are used to simplify addressing between numerous computers.
Subnets connect 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 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.
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 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.
