Method for managing congestion on a transmission link from a first item of network equipment to a second item of network equipment in a packet communication network, the first item of network equipment being associated with a first congestion detection application and the second item of network equipment being associated with a second congestion detection application, and said second application implementing, conjointly with said first application, a congestion control mechanism per class of service on said transmission link in which said second application performs the following steps, for at least one class of service: - receiving, for each said class of service, a first control message coming from the first congestion detection application, the first control message including information representing a first volume of data coloured by said class of service and transmitted by the first item of network equipment up to a first instant; - receiving, for each said class of service, a second control message coming from the first congestion detection application, the second control message including information representing a second volume of data coloured by said class of service and transmitted by the first item of network equipment up to a second instant; - on reception of each first control message, obtaining information representing a third volume of data coloured by said class of service and received by the second item of network equipment via said transmission link up to a third instant; - on reception of each second control message, obtaining information representing a fourth volume of data coloured by said class of service and received by the second item of network equipment via said transmission link up to a fourth instant; characterized in that said second application further performs the following steps: - determining a first divergence between said first volume of data and said second volume of data; - determining, for each class of service, a second divergence between said third volume of data and said fourth volume of data; and - generating or not, for each class of service, an alarm signal representing congestion on said transmission link of the data coloured by said class of service, according to a difference between said first divergence and said second divergence for said class of service. - receiving, for each said class of service, a first control message coming from the first congestion detection application, the first control message including information representing a first volume of data coloured by said class of service and transmitted by the first item of network equipment up to a first instant; - receiving, for each said class of service, a second control message coming from the first congestion detection application, the second control message including information representing a second volume of data coloured by said class of service and transmitted by the first item of network equipment up to a second instant; - on reception of each first control message, obtaining information representing a third volume of data coloured by said class of service and received by the second item of network equipment via said transmission link up to a third instant; - on reception of each second control message, obtaining information representing a fourth volume of data coloured by said class of service and received by the second item of network equipment via said transmission link up to a fourth instant; - determining a first divergence between said first volume of data and said second volume of data; - determining, for each class of service, a second divergence between said third volume of data and said fourth volume of data; and - generating or not, for each class of service, an alarm signal representing congestion on said transmission link of the data coloured by said class of service, according to a difference between said first divergence and said second divergence for said class of service.