Compact USB 2.0 10/100 Network Adapter
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Instant EtherFast
®
Series
Appendix F: Glossary
10BaseT - An Ethernet standard that uses twisted wire pairs.
100BaseTX - IEEE physical layer specification for 100 Mbps over two pairs of
Category 5 UTP or STP wire.
Adapter - Printed circuit board that plugs into a PC to add to capabilities or
connectivity to a PC. In a networked environment, a network interface card is
the typical adapter that allows the PC or server to connect to the intranet and/or
Internet.
Boot - To cause the computer to start executing instructions. Personal comput-
ers contain built-in instructions in a ROM chip that are automatically executed
on startup. These instructions search for the operating system, load it and pass
control to it.
Buffer - A buffer is a shared or assigned memory area used by hardware
devices or program processes that operate at different speeds or with different
sets of priorities. The buffer allows each device or process to operate without
being held up by the other. In order for a buffer to be effective, the size of the
buffer and the algorithms for moving data into and out of the buffer need to be
considered by the buffer designer. Like a cache, a buffer is a “midpoint hold-
ing place” but exists not so much to accelerate the speed of an activity as to
support the coordination of separate activities.
CAT 5 - ANSI/EIA (American National Standards Institute/Electronic
Industries Association) Standard 568 is one of several standards that specify
“categories” (the singular is commonly referred to as “CAT”) of twisted pair
cabling systems (wires, junctions, and connectors) in terms of the data rates
that they can sustain. CAT 5 cable has a maximum throughput of 100 Mbps
and is usually utilized for 100BaseTX networks.
CSMA/CD (Carrier Sense Multiple Access/Collision Detection) - The LAN
access method used in Ethernet. When a device wants to gain access to the net-
work, it checks to see if the network is quiet (senses the carrier). If it is not, it
waits a random amount of time before retrying. If the network is quiet and two
devices access the line at exactly the same time, their signals collide. When the
collision is detected, they both back off and each wait a random amount of time
before retrying.
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Domain - A subnetwork comprised of a group of clients and servers under the
control of one security database. Dividing LANs into domains improves per-
formance and security.
Ethernet - IEEE standard network protocol that specifies how data is placed
on and retrieved from a common transmission medium. Has a transfer rate of
10 Mbps. Forms the underlying transport vehicle used by several upper-level
protocols, including TCP/IP and XNS.
Fast Ethernet - A 100 Mbps technology based on the 10Base-T Ethernet
CSMA/CD network access method.
Hardware - Hardware is the physical aspect of computers, telecommunica-
tions, and other information technology devices. The term arose as a way to dis-
tinguish the “box” and the electronic circuitry and components of a computer
from the program you put in it to make it do things. The program came to be
known as the software.
Hot Swap - The ability to replace a card or other hardware part in a hardware
device without turning it off or losing functionality.
Hub - The device that serves as the central location for attaching wires from
workstations. Can be passive, where there is no amplification of the signals; or
active, where the hubs are used like repeaters to provide an extension of the
cable that connects to a workstation.
IEEE - The Institute of Electrical and Electronics Engineers. The IEEE
describes itself as “the world’s largest technical professional society—promot-
ing the development and application of electrotechnology and allied sciences
for the benefit of humanity, the advancement of the profession, and the well-
being of our members.”
The IEEE fosters the development of standards that often become national and
international standards. The organization publishes a number of journals, has
many local chapters, and several large societies in special areas, such as the
IEEE Computer Society.
IP Address - In the most widely installed level of the Internet Protocol (IP)
today, an IP address is a 32-binary digit number that identifies each sender or
receiver of information that is sent in packet across the Internet. When you
request an HTML page or send e-mail, the Internet Protocol part of TCP/IP
includes your IP address in the message (actually, in each of the packets if more
