Abstract: An arrangment to distribute send permission to any of the terminals in a telecommunication network when transmitting information between terminals which are connected to each other through a common ring bus controlled by a computer being located in each of the terminals. On the ring bus a signal word frame (SP) of HDLC format is circulating. The frame which is sent from any of the terminals comprises a send permission word in the form of a specific signal pattern. When one or more of the terminals connected to the bus is in a determined logic condition, that terminal receives the send permission which is first to occupy said logic state in relation to the position of the send permission frame on the loop. As soon as one of the terminals has received the send permission it transmits an abortion pattern within the frame to the bus. The frame then becomes invalid and no other terminal can have the send permission.