(19)

(11)

EP 0 993 721 A1

(12)

(43) Date of publication: 19.04.2000 Bulletin 2000/16 (21) Application number: 98932363.9 (22) Date of filing: 03.07.1998

(51) International Patent Classification (IPC)7: H04L 12/56, H04L 12/28, H04B 7/02, H04B 7/15 (86) International application number: PCT/GB9801/965 (87) International publication number: WO 9901/964 (14.01.1999 Gazette 1999/02)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 03.07.1997 GB 9714071 (71) Applicant: Worldpipe Limited Cambridgeshire CB2 5NH (GB)	(72) Inventor: BARTLETT, David, William-Worldpipe Limited Cambridgeshire CB2 5NH (GB) (74) Representative: Beresford, Keith Denis Lewis et al BERESFORD & Co.High Holborn2-5 Warwick Court London WC1R 5DJ London WC1R 5DJ (GB)