Patents Assigned to Forte Networks
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Patent number: 5548222Abstract: A termination control circuit is coupled to a far end of a cable. A modulated test signal is reflected back to a near end of the cable at a different frequency but at substantially the same level of attenuation as the test signal. Signal attenuation in the reflected signal is then measured to determine the amount of attenuation in the test signal. A second embodiment of the termination control circuit measures crosstalk by enabling and disabling termination resistors at the far end of the cable. A DC bias voltage located at the near end of the cable selectively turns on switching diodes to enable the termination resistor. Alternatively, both the attenuation and crosstalk circuits are combined together allowing both signal attenuation and crosstalk measurements with the same termination control circuit.Type: GrantFiled: September 29, 1994Date of Patent: August 20, 1996Assignee: Forte NetworksInventors: Gordon A. Jensen, Stephen M. Ernst
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Patent number: 5444695Abstract: A token ring local area network (LAN) testing apparatus is provided. The apparatus monitors history or status of token ring stations. Such information is useful in isolating token ring faults that may occur during its operation. The apparatus includes current and past memory lists that contain status information for each token ring station. The current station memory list contains addresses of all token ring stations that are present during a current neighbor notification process. The last station memory list contains addresses of all token ring stations that were present in the token ring during the neighbor notification process that was previous to the current neighbor notification process. A neighbor notification process is a conventional part of the token ring media access control (MAC) protocol. Included with the addresses in these lists is a determined one of a number of state characters that is indicative of station status.Type: GrantFiled: January 11, 1993Date of Patent: August 22, 1995Assignees: Forte Networks, Inc., Fluke CorporationInventors: Mark Copley, David G. Fish, Chris L. Odell, Charles H. Whiteside
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Patent number: 5425017Abstract: A testing apparatus for token ring local area networks (LANs) which can insert into the token ring network without requiring a separate port on a media access unit (MAU). The testing apparatus of the present invention is connected between a regular network station and the MAU. The testing apparatus is insertable into the network through the MAU, and the regular network station is able to insert into the network through the testing apparatus. Once inserted, the regular network station and the testing apparatus act as separate stations in series on the LAN. Due to its central position in this configuration, the testing apparatus is able to test for possible faults that might be present in the network and/or in the station to which it is connected. In addition, since the testing apparatus does not require a separate port on the MAU, no active user on the network needs to be disconnected for any extended period of time.Type: GrantFiled: January 11, 1993Date of Patent: June 13, 1995Assignees: Forte Networks, Inc, Fluke CorporationInventors: Mark Copley, David G. Fish, Gordon A. Jensen, Chris L. Odell, Charles H. Whiteside, Thomas S. Wisdom, Jr.
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Patent number: 5365513Abstract: A token ring local area network (LAN) testing apparatus is provided. The apparatus includes hardware and software that enables it to determine whether the testing apparatus is able to send frames into the token ring at a correct ring speed. The apparatus includes a conventional network interface card (NIC). The NIC includes two selectable clock signals, with the frequencies of the two clock signals being different. When the NIC is used in transmitting frames into the token ring, one of the two clock signals is selected to accompany the frames. The testing apparatus monitors whether frames and/or tokens are obtained from the token ring using the selected clock signal. If not, the testing apparatus causes the other clock signal to be selected. A determination of proper ring speed is made before a beacon condition occurs that would disrupt normal operation of the token ring.Type: GrantFiled: January 11, 1993Date of Patent: November 15, 1994Assignees: John Fluke Mfg. Co., Forte Networks, Inc.Inventors: Mark Copley, Charles H. Whiteside
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Patent number: 5363366Abstract: A token ring local area network (LAN) testing apparatus is provided. The apparatus includes hardware and software for keeping track of information related to the origination of a beacon frame that occurs due to a fault in the token ring. When a fault occurs in the token ring, a beacon frame is generated and this frame is useful in reporting the network domain or location that initiated the beaconing condition. This information is useful to the network manager in isolating the token ring fault. In addition to the first or original beacon frame, further or phantom beacon frames can be generated. These phantom beacon frames include those generated by other stations on the token ring experiencing a signal loss due to steps taken by the originating station as a result of the fault. These phantom domains are usually not beneficial to the network manager in isolating the fault on the token ring.Type: GrantFiled: January 11, 1993Date of Patent: November 8, 1994Assignees: Forte Networks, Inc., Fluke CorporationInventors: Thomas S. Wisdom, Jr., David G. Fish
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Patent number: D353342Type: GrantFiled: April 30, 1993Date of Patent: December 13, 1994Assignees: Fluke Corporation, Forte Networks, Inc.Inventors: Indle G. King, Roger L. Howell, Chris L. Odell, Jeffrey T. Samson, Harry B. Taylor, Steven W. Fisher