The invention relates to a method for matching a number N of reception equipment with a number M of external security modules, each reception equipment being provided with a unique identifier, and each external security module having a unique identifier and containing information about access rights of a user to digital data distributed by an operator. The method comprises the following steps: memorizing a list of identifiers of reception equipment in each external security module, memorizing a list of identifiers of external security modules in each reception equipment, and when an external security module is connected to data reception equipment, a check plan is carried out to determine whether or not the identifier for the security module is present in the list of memorized identifiers in the connected reception equipment, and the same check plan is carried out for the identifier in the list of identifiers memorized in the security module.