(19)

(11)

EP 0 856 177 A1

(12)

(43) Date of publication: 05.08.1998 Bulletin 1998/32 (21) Application number: 96935047.0 (22) Date of filing: 18.10.1996

(51) International Patent Classification (IPC):  G06F 17/ 30( . ) (86) International application number: PCT/GB1996/002572 (87) International publication number: WO 1997/015017 (24.04.1997 Gazette 1997/18)

(84) Designated Contracting States: BE CH DE DK ES FI FR GB IE IT LI NL PT SE (30) Priority: 19.10.1995 EP 19950307469 (71) Applicant: BRITISH TELECOMMUNICATIONS public limited company London EC1A 7AJ (GB)	(72) Inventor: McKEARNEY, Stephen Dorset BH10 4AM (GB) (74) Representative: Dutton, Erica L. G., et al  BT Group Legal Services, Intellectual Property Department, 8th Floor, Holborn Centre 120 Holborn London EC1N 2TE London EC1N 2TE (GB)