1. A device for monitoring service data for controlling traffic engineering modules ( 11, 12 ) and delivered by management modules ( 7 ) of a communications network, which device is characterized in that it comprises i) a memory ( 9 ) for storing rules each defined by one or more conditions representative of an event in the network associated with one of said traffic engineering modules ( 11, 12 ) and one or more actions representative of one or more commands to be executed by said associated module and ii) monitoring means ( 3 ) adapted, on receiving service data designating an event, to extract from said memory ( 9 ) one or more of the rules corresponding to said event and to deliver each command representative of an action associated with a condition representative of said event to said traffic engineering module ( 11, 12 ) associated with that event in the extracted rule.