Patent 5327534 Issued on July 5, 1994. Estimated Expiration Date: July 5, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A duplicate address condition in a computer network may be detected by a station of the type for attachment to a computer communications network, the network capable of maintaining communications among a plurality of stations, the station having means for receiving a frame, the frame having a source address field and a frame control field; means for maintaining an individual address of the station; means for maintaining a source address list of address, the source address list not containing the individual address; means for determining that a contents of the source address field in the frame matches at least one address in the source address list; means for determining that the frame control field of the frame has a predetermined contents; and, means, responsive to the source address of the frame matching at least one address in the source address list and the frame control field of the frame having the predetermined value, for setting an indicator that a duplicate address condition exists. The predetermined contents of the frame control field further comprises an indication that the frame is a predetermined type of control frame. The predetermined type of claim may be a beacon frame, a claim frame, or some other MAC protocol frame. The list of alias addresses may be stored in a content addressable memory. A cyclical redundancy check may be used for determining that bits from the source address field and bits from the frame control field are error free.
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