NetWare 4.1/9000 Concepts

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NetWare Glossary
P
See also “HPFS”; “Rights.”
Port, hardware
A connecting component that allows a microprocessor to communicate with
a compatible peripheral.
See also “Parallel port”; “Serial port.”
Port, software
A memory address that identifies the physical circuit used to transfer
information between a client LAN driver and a peripheral.
Power conditioning
Methods of protecting sensitive network hardware components against
power disturbances.
Power disturbances can be categorized in several ways:
• A transient (sometimes called a spike or surge). A very short, but extreme, burst
of voltage.
• Noise or static. A smaller change in voltage.
• Blackouts and brownouts. The temporary drop in or loss of electrical power.
Protection against power disturbances
Three types of protection are available:
• Suppression. Protects against transients. The most common suppression devices
are surge protectors that usually include circuitry to prevent excess voltage.
• Isolation. Protects against noise, using ferro-resonant isolation transformers to
control voltage irregularities.
• Regulation. Protects against brownouts and blackouts. The Uninterruptible
Power Supply (UPS) is the most commonly used form of regulation.
Proper use of power conditioning devices greatly reduces network
maintenance costs.