Patent ID: 6697943
Filing Date: 2004-02-24
Classification: H04L

Abstract:
A method of securing a communications link comprising the steps of:determining if a packet to be transmitted is a data packet or a control packet; if said packet is a data packet, computing a first error detection code (EDC) and attaching said first EDC to said packet; but if said packet is a control packet, computing a second EDC and attaching said second EDC to said packet; and checking a received EDC in a received packet against a computed third EDC, said received packet having a header; if said checking indicates a valid received EDC, checking said header; if said header is not a control header, processing said packet, otherwise discarding said packet; but if said checking indicates an invalid received EDC, checking said received EDC against a fourth EDC; if said checking against said fourth EDC indicates a valid received EDC, checking said header; if said header is a control header, processing said packet, otherwise discarding said packet; but if said checking against said fourth EDC indicates an invalid received EDC, discarding said packet.