The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 2003
Filed:
Aug. 03, 1999
Applicant:
Inventors:
Patrick M Overs, Caddington, GB;
Ronald R Aszkenasy, Chesham, GB;
Assignee:
3Com Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04J 3/16 ; H04J 3/22 ;
U.S. Cl.
CPC ...
H04J 3/16 ; H04J 3/22 ;
Abstract
The invention concerns an improvement to an auto-negotiation process for a link between network devices and in particular the avoidance of ambiguity when signals at a higher rate, such as 100BASE-Tx scrambled idle signals, resemble signals at a lower rate, such as 10BASE-T link pulses. Analog and digital filtration is employed to identify 100BASE-Tx energy more accurately and a resultant indicating signal is used in conjunction with another signal characteristic of the higher rate signals, such as a descrambler lock signal, to ensure that the link is not established unless the bit error rate is reasonably low.