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EP 4 771 838 A1

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(43) Date of publication: 08.07.2026 Bulletin 2026/28 (21) Application number: 24754953.8 (22) Date of filing: 07.08.2024

(51) International Patent Classification (IPC):  H04L 65/611(2022.01) H04L 65/1045(2022.01) H04L 65/612(2022.01) H04L 65/65(2022.01) (52) Cooperative Patent Classification (CPC): H04L 65/611; H04L 65/612; H04L 65/1045; H04L 65/65 (86) International application number: PCT/EP2024/072390 (87) International publication number: WO 2025/045544 (06.03.2025 Gazette 2025/10)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA Designated Validation States: GE KH MA MD TN (30) Priority: 01.09.2023 EP 23194919 (71) Applicant: British Telecommunications public limited company London, Greater London E1 8EE (GB)	(72) Inventors: NILSSON, Michael London Greater London E1 8EE (GB) APPLEBY, Stephen London Greater London E1 8EE (GB) TURNBULL, Rory London Greater London E1 8EE (GB) STEVENS, Timothy London Greater London E1 8EE (GB) (74) Representative: British Telecommunications public limited company Intellectual Property Department  9th Floor One Braham Braham Street London E1 8EE London E1 8EE (GB)