Cabletron Systems 100BASE-FX, Cabling Manual

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Glossary-9
Octet to Redundant
Octet
A numerical value made up of eight binary places (bits). Octets can
represent decimal numbers from zero (0000 0000) to 255 (1111 1111).
OID
Object Identifier.
OSI Model
Open Standards Interconnect. A model of the way in which network
communications should proceed from the user process to the physical
media and back.
Out-Of-Band
Performed without requiring the operation of the network technology.
Most commonly used in reference to local management operations.
Packet
A discrete collection of bits that form a block of information. Packets are
similar to frames. Packets are typically generated at the Network Layer
(Layer 3) of the OSI Model, and are encapsulated in frames before being
transmitted onto a network media.
Passive
Not utilizing per-port reclocking and regeneration of the signal which is
propagated throughout the device. Commonly applied to Token Ring
equipment to distinguish it from active devices.
Phantom Current
A weak voltage passed by Token Ring end nodes to the MAU to open the
relay
for that port.
Plenum
A cabling term which indicates a cable with insulating material that is
considered safe to use in return-air plenum spaces (in contrast to PVC
insulation) due to its low relative toxicity if ignited.
Port
A physical connector which is used as an interface to cabling with
modular or pinned connectors. Ports are associated with Interfaces.
Port Assignment
The association, through software management, of specific ports on a
network device to specific channels of a backplane. This assignment is
done on an individual port basis.
Protocol
A set of rules governing the flow of information within a communications
infrastructure. Protocols control operations such as frame format, timing,
and error correction. See also Architecture.
PVC
Polyvinyl Chloride. A material commonly used in the fabrication of cable
insulation. This term is used to describe a non-plenum rated insulating
material. See also Plenum. PVC releases toxic smoke when burned.
Redundant
Extra or contingent. A redundant system is one that is held in reserve
until an occurrence such as a failure of the primary system causes it to be
required.