(19)

(11)

EP 0 997 020 A2

(12)

(88) Date of publication A3: 08.04.1999 (43) Date of publication: 03.05.2000 Bulletin 2000/18 (21) Application number: 98935050.9 (22) Date of filing: 14.07.1998

(51) International Patent Classification (IPC)7: H04L 12/56, H04Q 11/04 (86) International application number: PCT/FI9800/591 (87) International publication number: WO 9904/536 (28.01.1999 Gazette 1999/04)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE Designated Extension States: AL LT LV MK RO SI (30) Priority: 14.07.1997 FI 972981 22.09.1997 FI 973746 09.04.1998 FI 980825 (71) Applicant: Nokia Networks Oy 00530 Helsinki (FI)	(72) Inventor: MA, Jian FIN-02940 Espoo (FI) (74) Representative: Honkanen, Jukka Samuli  Patent Agency Compatent Ltd.,Pitkänsillanranta 3 B 00830 Helsinki 00830 Helsinki (FI)