Patent SG-11201805542T-A (SG)
Title: Secure multiparty loss resistant storage and transfer of cryptographic keys for blockchain based systems in conjunction with a wallet management system
Inventor: WRIGHT CRAIG STEVEN
IPC: G06Q20/38
Filed: 2017-02-14
Abstract: INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property -, Organization 11M1111101110101011111 HO 11111 0111010 11111 10011111010110111110111011# International Bureau 0.. .... .. (10) International Publication Number ..... ..or:;„, (43) International Publication Date WO 2017/145010 Al 31 August 2017 (31.08.2017) WIPO I PCT (51) International Patent Classification: AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, G06Q 20/38 (2012.01) BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (21) International Application Number: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KH, KN, PCT/IB2017/050829 KP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, (22) International Filing Date: MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, 14 February 2017 (14.02.2017) NI, NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, (25) Filing Language: English TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, (26) Publication Language: English ZA, ZM, ZW. (30) Priority Data: (84) Designated States (unless otherwise indicated, for every 1603117.1 23 February 2016 (23.02.2016) GB kind of regional protection available): ARIPO (BW, GH, 1605026.2 24 March 2016 (24.03.2016) GB GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, 1619301.3 15 November 2016 (15.11.2016) GB TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, (71) Applicant: NCHAIN HOLDINGS LIMITED [AG/AG]; DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, Fitzgerald House, 44 Church Street, St. John's (AG). LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, (72) Inventors: WRIGHT, Craig Steven; c/o Urquhart-Dykes SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, & Lord LLP, 7th Floor Churchill House, Churchill Way, GW, KM, ML, MR, NE, SN, TD, TG). Cardiff CF10 2HH (GB). SAVANAH, Stephane; c/o Ur- Published: _ quhart-Dykes & Lord LLP, 7th Floor Churchill House, with international search report (Art. 2 1 (3)) — Churchill Way, Cardiff CF10 2HH (GB). — for every (81) Designated States (unless otherwise indicated, AG, AL, AM, = kind of national protection available): AE, = = = (54) Title: SECURE MULTIPARTY LOSS RESISTANT STORAGE AND TRANSFER OF CRYPTOGRAPHIC KEYS FOR WITH A WALLET MANAGEMENT SYSTEM = BLOCKCHAIN BASED SYSTEMS IN CONJUNCTION = _ 1 \ = = tif 19 Fig. 1 _ Third node = = 3 27 = ,,t,01, Networi = =......=- 0 Second node First node 23 = b ill ing lig 11 5 Ille III/W 13 17 1 1 — 11 Eavesdropper (57) : The invention provides a computer- implemented solution for controlling access to a computer-related resource such , I as, for example, a digital wallet. In one or more embodiments, the wallet may be implemented using a blockchain such as the Bitcoin © blockchain but the invention is not limited in this regard. Use of the invention during the initial set-up of the wallet can enable sub - in sequent operations such as wallet transactions to be handled in a secure manner over an insecure channel such as the internet. A 71' method according to an embodiment of the invention can comprise the steps of splitting a verification element (such as a private key Il ---- in an asymmetric cryptography pair) into a plurality of shares; determining a common secret at two or more nodes in a network; and IN using the common secret to transmit at least one share of the verification element between the two or more nodes. The shares can be C split such that no share on its own is sufficient to arrive at the verification element. This means that no one party stores the entire ei private key, providing for enhanced security of the key. Two or more shares are required to restore the key. The shares are stored at 0 separate locations one of which is an independent back-up or safe-storage location. If one of the other shares becomes unavailable, the share can be retrieved from back up to ensure that the key (and thus the controlled resource) is still accessible. To [Continued on next page] WO 2017/145010 Al 1#11101MOMMIONOIDEOMMEIN001111010110MOVOIS ensure safe transmission then used to or a message generate an encryption key. comprising it, to ensure that of the share(s), the The the common secret is generated at two different nodes independently of each other encryption key can be used to encrypt at least one share of the verification share(s) are transmitted securely. and element,