User's Manual

SPEEDLAN 4100 & 4200 Installation and Operation User Guide
Glossary-6
Ethernet
This is the most popular physical layer LAN technology in use today. Other LAN types include Token Ring, Fast Ethernet,
Fiber Distributed Data Interface (FDDI), Asynchronous Transfer Mode (ATM) and Local Talk. Ethernet is popular because it
strikes a good balance between speed, cost and ease of installation. These benefits, combined with wide acceptance in
the computer marketplace, create the ability to support virtually all-popular networks and make Ethernet an ideal network-
ing technology for most computer users today. The Institute for Electrical and Electronic Engineers (IEEE) defines the Ether-
net as IEEE Standard 802.3. This standard defines rules for configuring an Ethernet, as well as specifying how elements in
an Ethernet network interact with one another. By adhering to the IEEE standard, network equipment and network proto-
cols will communicate efficiently.
Ethernet Switch
This device helps expand the Ethernet network. LAN switches can link four, six, ten or more networks together, and have
two basic architectures. This switch “cuts through” and “stores and forwards” as well. This technique takes more time to
examine the entire packet, but it allows the switch to catch certain packet errors and keep them from propagating through
the network. A switch also operates between the DataLink and Network Layer of the OSI model. It reads the MAC address
and will either bridge it to the Physical Layer or route to the Network Layer.
Fade Margin
The difference between the receiver signal input level and the receiver sensitivity. Fade margin is usually considered the
safety factor allowing the system to remain operating under additional forms of attenuation.
Fading
The loss of signal strength due to changes in the atmosphere.
Fault
This section of the browser gives the user a detailed list of alarm activity. Along with the alarm activity, the Event Log also
time stamps an alarm, so the user is able to determine when an event occurred, and at what time the event cleared. The
date and time fields are derived from the time read by the radio on the network time server.
Federal Communications Commission (FCC)
Government organization appointed by the U.S. President that regulates interstate communications (by use of licenses,
standards, rates, etc.).
Firmware
Alterable programs in semitransparent storage (e.g., some type of read-only or flash reprogrammable memory).