The present invention relates to a method for communicating in a network, comprising a) a secondary station preparing the transmission to a primary station of a message comprising at least a data field for containing data in an allocated resource, said resource comprising a plurality of resource blocks, and b) if the size of the allocated resource is bigger than required for the size of the message, the secondary station dividing the allocated resource in a first portion and a second portion, each portion comprising at least one resource block, c) the secondary station transmitting the message to the primary station in the first portion of the resource, d) the secondary station preventing from transmitting in the second portion of the resource.