Abstract: A computer-implemented method of managing telecommunications between telephone line subscribers is provided. The method includes at a first telecommunications operator, receiving from a first telecommunications terminal associated with a first subscriber a connection or message request to connect or send a message to a second subscriber. The connection or message request contains a portable extension number associated with the second subscriber. The method includes resolving the portable extension number to discover information regarding a telephone number and second telecommunications operator used by the second subscriber, routing the connection or message request to the second subscriber via the second telecommunications operator using at least the telephone number, and including an identifier so that the second telecommunications operator knows that the connection or message request originated for a portable extension number.