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Telecom Dictionary - O

Object - (1) A unit, piece, entity, or component of information, or (2) in telecom services, it is a numeric value that is used to represent an aspect of a device.

Object Code - This programming term describes the executable form of the software (i.e., the program).

Object Handle - This piece of code is used by a programmer to point to some specific piece of information (the object).

Object Oriented Programming (OOP) - This is a type of software programming that maintains and uses many data-containing objects to carry out the desired behavior.

Octet - This is an 8-bit byte.

Odd Parity - This is a way to detect errors in data that is being transmitted in which the parity bit checks for odd numbers of 1s.

Off-Hook - When the telephone handset or receiver is off the cradle; the circuit is closed (active) and ready to communicate information.

Off/On Hook - These is a modem function that causes the modem to be taken off-hook and then put back on-hook again.

Off-Peak - This is the time of the day, not during business hours (typically 7:00 pm to 7:00 am), when telephone rates are lower than during high-traffic, on-peak times (during business hours).

Ohm - The unit of resistance. One ohm of resistance will let one ampere of current pass at a potential of 1 volt.

Ohm's Law - This is the electrical circuit law that states that V=IR. That is, the electric potential (in volts) equals the current (in amperes) times the resistance (in ohms).

On-Hook - When the telephone handset or receiver is on the cradle; the circuit is open (inactive) and cannot communicate information.

Online - When (1) a device is actively connected to a computer (and ready to receive instructions), or (2) you are connected to the internet.

OOP - see Object Oriented Programming.

Open Circuit - To transmit a signal, an electrical circuit must be a complete, closed loop. When this loop is broken or not closed, the circuit is said to be open.

Open Systems - When all types and brands of hardware and software equipment are interchangeable and able to function together.

Operating Systems (OS) - This is a computer's primary software program, and it controls all basic operations of the computer. MS Windows and Linux are examples of operating systems.

Optical Fiber - This is a filament that is made of dielectric materials that has the purpose transmitting light, which may or may not carry information.

Optical Receiver - A circuit that converts an optical signal to an electrical signal.

Orbit - This term describes the motion of a body of matter around another more massive body and is governed by the force of gravity. Johannes Kepler first observed that the planets in our solar system orbit around the Sun in the shape of an ellipse. A body follows an orbit because it feels forces in two distinct directions acting on it: (1) directly towards the more massive body (i.e., a star or planet) and (2) tangent to the orbital path. See polar orbit, Clarke orbit.

Orbital Period - This is the time that it takes a revolving body (i.e., a satellite) to undergo one complete circumnavigation of its orbit.

Orbit Raising - This is the process for placing a satellite into its orbit once it has been separated from the launch vehicle that carried it into space.

Orbital Slots - These are the exact orbital locations of satellites (in degrees).

Originate - This is one of two main modes of a modem (the other being answer mode), and it is the mode used to transmit information (the answer mode is used to receive information).

Originate Mode - This is the first mode of operation of a modem. It begins the data phone call by dialing the phone, finding the remote modem and connecting to it.

Oscilloscope - This is a device that displays on a cathode ray tube screen a voltage or current signal waveform.

OS - see Operating Systems.

Outage - This is an interruption of service.

Outlet - A set electrical contacts into which electrical devices are plugged.

Overwrite - To replace the contents of a file with different contents.