(19)

(11)

EP 0 829 160 A1

(12)

(43) Date of publication: 18.03.1998 Bulletin 1998/12 (21) Application number: 97914010.0 (22) Date of filing: 27.03.1997

(51) International Patent Classification (IPC):  H04N 7/ 15( . ) H04M 3/ 56( . ) H04L 12/ 18( . ) H04M 7/ 12( . ) (86) International application number: PCT/CA1997/000204 (87) International publication number: WO 1997/037484 (09.10.1997 Gazette 1997/43)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 29.03.1996 US 19960014335P (71) Applicant: NORTHERN TELECOM LIMITED Montreal, Quebec H2Y 3Y4 (CA)	(72) Inventors: CRADDOCK, A., Julian Greely, Ontario K4P 1E7 (CA) DIXON, Fred Ottawa, Ontario K2B 8J5 (CA) NG, Charles Ottawa, Ontario K1T 3L7 (CA) (74) Representative: Berkson, Michael David  Nortel Patents, London Road Harlow, Essex CM17 9NA Harlow, Essex CM17 9NA (GB)