(19)

(11)

EP 1 417 497 A1

(12)

(43) Date of publication: 12.05.2004 Bulletin 2004/20 (21) Application number: 02747005.3 (22) Date of filing: 15.07.2002

(51) International Patent Classification (IPC)7: G01R 31/08, G06F 11/00 (86) International application number: PCT/US2002/022215 (87) International publication number: WO 2003/007005 (23.01.2003 Gazette 2003/04)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR Designated Extension States: AL LT LV MK RO SI (30) Priority: 13.07.2001 US 904623 (71) Applicant: Ciena Corporation Linthicum, MD 21090 (US)	(72) Inventors: GULLICKSEN, Jeffrey Mountain View, CA 94043 (US) KISH, William Saratoga, CA 95070 (US) TEDIJANTO, Theodore, E. Cupertino, CA 95014 (US) (74) Representative: Tothill, John Paul et al Frank B. Dehn & Co.179 Queen Victoria Street London EC4V 4EL London EC4V 4EL (GB)