In a communications network, such as a telephone network or a computer network, an exchange that (a) is connected to one or more satellite exchanges and (b) has one or more attendant positions, i.e., operator positions. Note: The connections between main exchanges and satellite exchanges may be via electronic or fiber optic trunks. See also  attendant position,  computer network,  connection,  electronic,  exchange,  exchange access,  exchange area,  exchange line,  fiber optic trunk,  operator,  satellite exchange,  telephone network,  trunk.