Network message security method and apparatus
AssigneeUngermann-Bass, Inc.
InventorsBrian Schanning, Sadredin Tavana, Steven E. Archambault, Carl G. Hayssen, III
Life of this patent
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Abstract
A security system for local area networks (LAN) to prevent eavesdropping of or to control access to LAN traffic at repeater or concentrator ports. The security system determines which repeater ports are to have security activated according to a given set of criteria. For ports with security activated, the contents of the data field of data frame transmitted from the repeater port to the local device are replaced with an arbitrary bit pattern.
Claims18
In a local area network having a plurality of input/output devices coupled to a multiport repeater, a method for securing data on the network comprising the steps of:
- receiving at the repeater a data frame having a data field and a frame check sequence field;
- replacing a content of said data field with a substitute bit pattern to form a secured data field;
- replacing a content of said frame check sequence field with a new frame check sequence field calculated from said substitute bit pattern;
- and
- wherein a valid secured data frame is formed.
In a local area network having a plurality of input/output devices coupled to a multiport repeater, a repeater structure for securing data on the local area network comprising:
- means for replacing a content of a data field of a data frame received at said repeater with a substitute bit pattern to form a secured data field;
- and
- means for replacing a content of a frame check sequence field of said data frame with a new frame check sequence field calculated from said substitute bit pattern.
In a local area network having a plurality of input/output devices coupled to a multiport repeater, a repeater structure for securing data on the local area network comprising:
- means for replacing a content of a data field of a data frame received at said repeater with a substitute bit pattern to form a secured data field;
- a security selection logic circuit, coupled to a local area network management system, to said means for replacing a content of a data field and to a receive port of said repeater, having:
- (i) means for identifying given ones of a plurality of data frames received at said receive port to be secured;
- (ii) means for activating said means for replacing;
- (ii) means for calculating a frame check sequence field from said substitute bit pattern for said given data frames containing said secured data field.
Dependencies are inferred from the claim text.