Connectionless communication system

A communication system for transmitting at least one fixed-length cell converted from a variable-length information including data and a destination of the data, comprising:

• a plurality of routing control means for receiving said fixed-length cell converted from said variable-length information, for analyzing the destination of the data and for controlling a routing of said fixed-length cell based on the analyzed destination, said routing control means including error detecting means for detecting an error of said variable-length information in said fixed-length cell and alerting means for alerting the error to the other of said plurality of routing control means;
• and
• a network for connecting said routing control means to each other by one of a fixed capacity path and a variable capacity path.

A communication system for transmitting at least one fixed-length cell converted from a variable-length information including data and a destination of the data, comprising:

• a plurality of routing control means for receiving said fixed-length cell converted from said variable-length information, for analyzing the destination of the data and for controlling a routing of said fixed-length cell based on the analyzed destination, said routing control means including error processing means for detecting an error in a first cell, having a message header, of a plurality of cells into which a message corresponding to the variable-length information has been segmented, and rejecting all of the cells following the first cell in which a message identifier has been placed, and alerting means for alerting the error to the other of said plurality of routing control means;
• and
• a network for connecting said routing control means to each other by a fixed capacity path or a variable capacity path.

An exchange apparatus, connected via a virtual connection to a converting apparatus, the converting apparatus converting information including data and destination information from a transmitting side into at least one cell which is a fixed-length packet and assigning a header indicating a destination to the cell, said exchange apparatus receiving the cell via the virtual connection, said exchange apparatus comprising:

• switching means for switching the cell according to the header of the cell;
• and
• routing processing means, connected to said switching means, for receiving the cell with the header, for analyzing the destination information of the information and for generating a corresponding result, for rewriting the header of the cell according to the result, for sending the cell to a receiving side in response to said result, for detecting an error of said information in said cell, and for alerting said error to another exchange apparatus which is located in said receiving side of said cell.