Object ID - Object Identification
The name that uniquely distinguishes one object from all others. The short
form of an Object ID is unique on a local
machine, or a LAN. A longer form of the Object ID may be required to
uniquely identify it on a WAN. (See Universal Name
Space) If the local machine name or LAN name is part of the Object ID, special consideration is required to support Object
Object Mobility Location Transparency
Location Transparency. The ability to move an Object from one machine or LAN
to another without disrupting operations or
modifying source code.
OC - Optical Carrier
defined for SONET. Levels include but are not limited
to: OC-1 = 1 DS3, 28 DS1, 672
DS0; OC-3 = 3 DS3, 84 DS1, 2016 DS0; 0C-12 = 12 DS3, 336
DS1s, 8064 DS0s; OC-48 = 48 DS3s, 1344 DS1s, 32256
DS0s; and OC-192 = 192 DS3s, 5376 DS1s, 129,024 DS0s.
OCC - Other Common Carrier
Carriers providing long distance communications service. Not part of
the original AT&T system.
OCEF - Optical Cable Entrance Facility
area providing space for splicing fibers connecting equipment to outside
OCR - Optical Character Recognition
data using a machine that visually scans the characters in a document and
converts that data into standard form which can be
stored on conventional magnetic medium, e.g. floppy or hard disk.
A term for eight (8) bits that is
sometimes used interchangeably with "byte" to mean the same thing.
OCUDP - Office Channel Unit Data Port
channel bank unit used to interface between the channel bank and the
customer's DDS CSU or DSU.
One of many methods for
detecting errors in transmitted data. An extra bit is added to each character sent and that bit is given a value of
0 (zero) or 1 (one) such that the total number of
ones in the character will be odd.
The signal that the
telephone receiver has been lifted (activated). Originating off hook
activates a dial tone on switched networks.
Destination off hook completes a call (and activates minute-by-minute billing for long distance calls).
Office Repeater Bay - ORB
provides the interface between a T-carrier circuit and the DSX. It
regenerates the incoming signal to the DS-1 level and
provides line powering to the outside plant repeaters.
Phone calls which are
carried in part, on a network but are destined for a phone not on the
network (i.e. some part of the conversation's journey
will be over the public switched network or over
someone else's network.
When the phone handset is resting
in its cradle. The phone is not connected to any particular line.
One Plus - 1+
Customer ability to
access the long distance service provider of their choice by first dialing
1, then the long distance number. Equal Access
guaranteed by the 1982 AT&T MFJ. 1+ is an outbound service where the calling station pays the charges.
Telephone calls which stay on a
customer's private network, traveling by private line from beginning to end are said to be on-net. In other words,
there are no leased components within the communication path of the circuit.
1. A trunk between a switch
(PBX) and a central office, or between central offices, where traffic originates from only one end. 2. A trunk
circuit which can be seized at only one end.
OOF - Out Of Frame
Condition counter that
increments every time either the network or the DTE equipment senses an error in the framing bits of a circuit or device.
Employee of telephone company, or
an individual business or institution, who aids in the completion of phone calls.
Operator Service Call - OSC
that is placed through a human or automated operator (0+) .
Operator Service Provider - OSP
A new breed
of long distance phone company which handles operator-assisted calls - in
particular, Credit Card, Collect, Third Party Billed
A device to amplify an
optical signal without converting the signal from optical to electrical back again to optical energy.
communications, a device used to reduce the intensity of the optical signal.
Any filament made of
dielectric materials, that guides light, whether or not it is used to
transmit signals. It is almost the ideal
transmission medium because of: 1. Transmission losses are very small. 2. Bandwidth is greater than any other
transmission medium known today. 3. Fiber is immune
to electromagnetic interference. 4. Fiber does not radiate. 5. Many
strands of fiber carrying much information can be put
in the same bundle and they won't interfere with each other. 6. It's raw material, silica (sand) is the second most abundant
element on earth.
Optical Time Domain Reflectometer - OTDR
device that measures distance to a reflection surface by measuring the time
it takes for a lightwave pulse to reflect from the
surface. Reflection surfaces include the ends of cables and breaks in fiber. Heavily used during fiber cuts
to locate the exact point of the cut.
OPX - Off-Premise Extensions
station line at a location other than the premise where the PBX (or local
exchange service) is located.
Order Wire Circuit
A voice or data circuit
used by telephone company technical control and maintenance personnel for the coordination and control action relating to
activation, deactivation, change, rerouting, reporting and maintenance of communication systems and
The person, location or
ANI that initiated a call, order, etc.
Outward Sending - Call
Originating - Dialing Out.
1) The use of transmission facilities other than the primary channel
bandwidth for simple transmission control pulses. Contrast with in-band signaling.
2) The use of narrow band filters to place the voice signal on a carrier
channel below 3,400 Hz, reserving the 3,400 - 3,700 Hz band for supervisory
The process of transmitting
address information over a trunk from one switching center to another.
Additional traffic beyond the
capacity of a specific trunking group which is then offered to another group or line.
In communications, all information
such as control, routing and error-checking characters, that is in addition to user-transmitted data.
In frame relay
service definition, over subscription occurs when the sum of the CIRs for
all PVCs on a port exceed the port connection
speed. Subscription levels of 200% are typically allowed. Oversubscription is possible because of dynamic
capacity allocation in modern data networks.