User's Manual Part 2

User’s Guide Glossary
D
E
Glossary
bps: bits per second. A measure of the data
transmission rate.
Symbols:
802.11: 802.11 is a family of specifications for
wireless local area networks (WLANs)
developed by a working group of the Institute
of Electrical and Electronics Engineers (IEEE).
The original specification provides for an
Ethernet Media Access Controller (MAC) and
several physical layer (PHY) options, the most
popular of which uses GFSK modulation at
2.4GHz, enabling data rates of 1 or 2Mbps.
Since its inception, two major PHY
enhancements have been adopted and
become "industry standards".
DHCP: Dynamic Host Configuration Protocol
(DHCP) is a communications protocol that lets
network administrators manage centrally and
automate the assignment of Internet Protocol
(IP) addresses in an organization's network.
Using the Internet Protocol, each machine that
can connect to the Internet needs a unique IP
address. When an organization sets up its
computer users with a connection to the
Internet, an IP address must be assigned to
each machine. Without DHCP, the IP address
must be entered manually at each computer
and, if computers move to another location in
another part of the network, a new IP address
must be entered. DHCP lets a network
administrator supervise and distribute IP
addresses from a central point and
automatically sends a new IP address when a
computer is plugged into a different place in
the network.
802.11b adds CCK modulation enabling data
rates of up to 11Mbps, and 802.11a specifies
OFDM modulation in frequency bands in the 5
to 6GHz range, and enables data rates up to
54Mbps.
A
AAA: Authentication, Authorization and
Accounting. A method for transmitting roaming
access requests in the form of user credentials
(typically user@domain and password),
service authorization, and session accounting
details between devices and networks in a
real-time manner.
DNS: Domain Name Service. An Internet
service that translates a domain name such as
gemtek-systems.com to an IP address, in the
form xx.xx.xx.xx, where xx is an 8 bit hex
number.
authentication: The process of establishing the
identity of another unit (client, user, device)
prior to exchanging sensitive information.
EAP: Extensible Authentication Protocol.
Defined in [RFC2284] and used by IEEE
802.1x Port Based Authentication Protocol
[8021x] that provides additional authentication
methods. EAP-TLS (Transport Level Security)
provides for mutual authentication, integrity-
protected ciphersuite negotiation and key
exchange between two endpoints [RFC2716].
EAP-TTLS (Tunneled TLS Authentication
Protocol) provides an authentication
negotiation enhancement to TLS (see Internet-
Draft <draft-ietf-pppext-eap-ttls-00.txt>).
B
backbone: The primary connectivity mechanism
of a hierarchical distributed system. All
systems, which have connectivity to an
intermediate system on the backbone, are
assured of connectivity to each other. This
does not prevent systems from setting up
private arrangements with each other to
bypass the backbone for reasons of cost,
performance, or security.
Bandwidth: Technically, the difference, in Hertz
(Hz), between the highest and lowest
frequencies of a transmission channel.
However, as typically used, the amount of data
that can be sent through a given
communications circuit. For example, typical
Ethernet has a bandwidth of 100Mbps.
Gemtek Systems Page 145