TOPS - Traffic Operator Position System is a computerized operator telephone switchboard

Telephone switchboard

A switchboard was a device used to connect a group of telephones manually to one another or to an outside connection, within and between telephone exchanges or private branch exchanges . The user was typically known as an operator...

 designed by [Bell Northern Research Labs for the SP-1 4 Wire Switch] in the early 1970s and still widely used today by toll and directory-assistance operators. The terminals known as 'TOPS Positions' are usually connected to Nortel

Nortel

Nortel Networks Corporation, formerly known as Northern Telecom Limited and sometimes known simply as Nortel, was a multinational telecommunications equipment manufacturer headquartered in Mississauga, Ontario, Canada...

 DMS-100

DMS-100

The DMS-100 Switch is a line of Digital Multiplex System telephone exchange switches manufactured by Nortel Networks.The purpose of the DMS-100 Switch is to provide local service and connections to the PSTN public telephone network. It is designed to deliver services over subscribers' telephone...

 and DMS-200 telephone switches.

Systems

Below are some of the different TOPS systems developed:

TOPS MP
TOPS Multipurpose Position. An earlier-generation operator position for toll and assistance and directory assistance.

TOPS - MPX
A previous-generation operator position based on industry-standard personal computer customized with Nortel Networks components and interfaces to provide connectivity with IBM directory databases.

TOPS
Traffic Operator Position System. Nortel Networks' operator services system based on the DMS TOPS switch.

TPC
TOPS Position Controller. (Previous generation equipment required for TOPS MP positions) The processing unit that provides intelligence and interfaces to the switch for up to four TOPS MP operator positions.

Technical details

The Class 5

Class 5 telephone switches

A Class 5 telephone switch is a telephone switch or telephone exchange in the Public Switched Telephone Network located at the local telephone company's central office, directly serving subscribers. Class 5 switch services include basic dial-tone, calling features, and additional digital and data...

 switch system for Traffic Operator Position System (TOPS) enables the definition of up to 255 unique queue

Queue

A queue is a particular kind of collection in which the entities in the collection are kept in order and the principal operations on the collection are the addition of entities to the rear terminal position and removal of entities from the front terminal position. This makes the queue a...

s of calls to operators—and up to 255 unique profiles defining the responsibilities of operators and teams, that is, the queues from which they can draw calls. This technology was first introduced in the DMS 200/300. Previously, only four queues were available, all straight-line models, forecasted with Erlang distribution algorithm

Algorithm

In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...

s and table look-ups. Now, a vast array of queues were available, with variable grades of service, served by multiple queues of operators in both primary and secondary capacity. The lookup tables were no longer capable of forecasting for this complex queueing environment.

Above: A picture of a keyboard from the Nortel TOPS position (terminal)