(19)

(11)

EP 0 870 372 A1

(12)

(43) Date of publication: 14.10.1998 Bulletin 1998/42 (21) Application number: 97910182.0 (22) Date of filing: 24.10.1997

(51) International Patent Classification (IPC):  H04B 7/ 08( . ) H04L 1/ 06( . ) (86) International application number: PCT/CA1997/000801 (87) International publication number: WO 1998/019402 (07.05.1998 Gazette 1998/18)

(84) Designated Contracting States: DE FR GB SE (30) Priority: 25.10.1996 CA 19962188845 20.12.1996 US 19960777674 (71) Applicant: NORTHERN TELECOM LIMITED Montreal, Quebec H2Y 3Y4 (CA)	(72) Inventor: TODD, Stephen, Ross Ottawa, Ontario K1Y 3R8 (CA) (74) Representative: Ryan, John Peter William, et al  Nortel Patents, London Road Harlow, Essex CM17 9NA Harlow, Essex CM17 9NA (GB)