Abstract: Several nodes are connected to a ring structure by means of communication lines in a network for packet-oriented data traffic. Each node is connected to lines of the ring structure. A buffer circuit is provided between the high speed interfaces for reading a routing information on the head of a data packet. The buffer circuits are structured in such a manner that the delay time in the transit traffic is smaller than, for example, 10 .mu.s. Several users are connected at the node. A wait line circuit is provided for each user. A controller ensures the processing of the data packets in the transit, insert and extract modes.

Abstract: A method and apparatus are provided for observing the progress in time of an object program executed by a computer system. Information items relating to the flow of the object program are detected by an observation tool at an interface of the computer system being evaluated. Unambiguously identifiable observation points in the form of output commands are inserted at specifically selected points in a source program allocated to the object program. The observation points are stored in a table in a database in the observation tool. When the source program is executed, identification signals associated with the observation points are sent to the observation tool by the computer system. The observation tool calculates object program events which specify object program execution times for each object computer of the computer system. The calculated events are evaluated in the observation tool in the program language of the source program with reference to the observation points stored in table form.