MULTIPORT MODEM AND THE USE THEREOF IN A METHOD AND A SYSTEM FOR TESTING A MULTILEVEL COMMUNICATION NETWORK

摘要

MULTIPORT MODEM AND THE USE THEREOF IN A METHOD AND A SYSTEM FOR TESTING A MULTILEVEL COMMUNICATION NETWORK A method of testing a communication network that comprises first and second multiport modems communicating with each other through a transmission channel. Each of said modems is provided with a number of input/output interfaces and each of the interfaces on either modem is associated with a corresponding interface on the other modem. In accordance with the method of the present invention, a test request is applied to one of the interfaces on the first multiport modem, which responds thereto by generating a test configuration code identifying that interface. This modem is then caused to assume a so-called test configuration, in which only that interface to which the test request was applied is active, and a test command comprising an indication of the test to be performed and a link level identifier is applied to that interface. If the identifier designates the link level to which the first modem belongs, this modem will control the test specified in the test command. If another link level is designated then the test command and the test configuration code will both be sent to the second multiport modem. The second modem will then decode the link level identifier and, if the link level so designated is not the one to which is pertains, will assume a test configuration such that only the interface associated with the first modem interface which received the test request will be active, and the test command will be applied to that active interface. In accordance with another aspect of the invention the test configuration code also identifies the bit rate associated with the test command. The invention also provides a test system that implements the above method. The invention further provides an improved multiport modem to be used in conjunction with the test method and system mentioned above. FR9-79-013