11 | Terminology 10BaseT - Physical Layer Specification for Twisted-Pair Ethernet using Unshielded Twisted Pair
wire at 10Mbps. This is the most popular type of LAN cable used today because it is very cheap
and easy to install. It uses RJ-45 connectors and has a cable length span of up to 100 meters.
There are two versions, STP (Shielded Twisted Pair) which is more expensive and UTP
(Unshielded Twisted Pair), the most popular cable. These cables come in 5 different categories.
However, only 3 are normally used in LANs, Category 3, 4 and 5. CAT 3 TP (Twisted Pair) cable
has a network data transfer rate of up to 10Mbps. CAT 4 TP cable has a network data transfer
rate of up to 16Mbps. CAT 5 TP cable has a network data transfer rate of up to 100Mbps.
Access Point - A device that is able to receive wireless signals and transmit them to the wired
network, and vice versa - thereby creating a connection between the wireless and wired
networks.
Ad Hoc - An ad hoc wireless LAN is a group of computers, each with LAN adapters, connected as
an independent wireless LAN.
Adapter - A device used to connect end-user nodes to the network; each contains an interface to
a specific type of computer or system bus, e.g. EISA, ISA, PCI, PCMCIA, CardBus, etc.
Auto-Negotiation - A signaling method that allows each node to define its operational mode (e.g.,
10/100 Mbps and half/full duplex) and to detect the operational mode of the adjacent node.
Backbone - The core infrastructure of a network. The portion of the network that transports
information from one central location to another central location where it is unloaded onto a local
system.
Base Station - In mobile telecommunications, a base station is the central radio
transmitter/receiver that maintains communications with the mobile radiotelephone sets within its
range. In cellular and personal communications applications, each cell or micro-cell has its own
base station; each base station in turn is interconnected with other cells' bases.
Bitmap – A Windows and OS/2 bitmapped graphics file format. Bitmap files provide formats for 2,
16, 256, or 16 million colors. It uses the extension .BMP.
BSS - BSS stands for "Basic Service Set". It is an Access Point and all the LAN PCs that are
associated with it.
CHAP - When authenticating using Challenge Handshake Authentication Protocol (CHAP), the
knowledge of the password, rather than the password itself is what is sent by the client. With
CHAP, the VPN Broadband Router sends the remote client a challenge string. The remote client
uses the challenge string and the password, and creates a Message Digest-5 (MD5) hash which is
then forwarded to the VPN server. The VPN server computes the same hash calculation and
compares the result with the hash sent by the client. If they match, the remote client is
considered an authentic user.
CSMA/CA - Carrier Sense Multiple Access with Collision Avoidance
DES - Data Encryption Standard. A cryptographic encryption algorithm that is part of many
standards.