# US 2018/0322259 A1 · Method and system for content and service sharing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0322259 A1 - Document ID: US20180322259A1 - Status: Published application - Kind: A1 - Application number: 15/585,194 - Filed: 2017-05-03 - Published: 2018-11-08 - Earliest claimed: 2017-05-03 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Hillel SOLOW; Yossi Tsuria; Avraham Poupko; Shabtai Atlow - Web page: https://patentgrep.com/patent/US20180322259A1 ## CPC - G06F 21/105: {Arrangements for software license management or administration, e.g. for managing licenses at corporate level} - G06F 21/645: {using a third party} - H04L 9/0819: {Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) (network architectures or network communication protocols for key distribution in a packet data network H04L63/062)} - G06F 21/1085: {Content sharing, e.g. peer-to-peer [P2P]} - G06F 2221/2151: Time stamp - H04L 2209/603: Digital right managament [DRM] - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract In one embodiment, an instruction is received at a blockchain server from a first digital rights management (DRM) client, the instruction including an instruction to transfer a DRM license to an encrypted content item to a second DRM client. A block to be recorded in a blockchain, is created, the block including a content item ID of said encrypted content item, one of a device ID of a device including the second DRM client or a user ID of a user of the second DRM client, DRM license information for said DRM license, and a DRM decryption key for decrypting said encrypted content item. The block is recorded in the blockchain. A confirmation message is sent to the second DRM client confirming that the block was written to the blockchain. Related systems, methods, and apparatuses are also described. ## Claims ### Claim 1 A method comprising: receiving an instruction at a blockchain server from a first digital rights management (DRM) client, the instruction comprising an instruction to transfer a DRM license to an encrypted content item to a second DRM client; creating a block to be recorded in a blockchain, the block comprising: a content item ID of said encrypted content item; one of a device ID of a device comprising the second DRM client or a user ID of a user of the second DRM client; DRM license information for said DRM license; and a DRM decryption key for decrypting said encrypted content item; recording the block in the blockchain; and sending a confirmation message to the second DRM client confirming that the block was written to the blockchain. ### Claim 2 (depends on 1) The method according to claim 1 wherein the block further comprises a blockchain ID. ### Claim 3 (depends on 1) The method according to claim 1 wherein the instruction to transfer the DRM license to the second DRM client comprises an instruction to transfer the DRM license for a limited amount of time. ### Claim 4 (depends on 1) The method according to claim 1 wherein the instruction to transfer the DRM license to the second DRM client comprises an instruction to permanently transfer the DRM license. ### Claim 5 (depends on 1) The method according to claim 1 wherein the DRM license comprises a license expiration date. ### Claim 6 (depends on 1) The method according to claim 1 wherein the decryption key comprises one share of different parts of the decryption key, wherein said one share is used in combination with at least one other share to decrypt the encrypted content item. ### Claim 7 (depends on 1) The method according to claim 1 and further comprising receiving a revocation message from the first device cancelling the DRM license of the second DRM client. ### Claim 8 (depends on 7) The method according to claim 7 wherein the revocation message is received prior to an expiration date of the DRM license transferred to the second DRM client. ### Claim 9 (depends on 7) The method according to claim 7 wherein the instruction to transfer the DRM license to the second DRM client includes an indication that the first DRM client may send a revocation message. ### Claim 10 (depends on 1) The method according to claim 1 and further comprising sending a message to at least one of the first DRM client and the second DRM client, the message comprising a secure time stamp. ### Claim 11 (depends on 1) The method according to claim 1 wherein the DRM license comprises a license for a fixed number of uses of the content item, and the receiving step may be repeated up to the fixed number of times. ### Claim 12 (depends on 11) The method according to claim 11 wherein the step of recording the block in the blockchain comprises recording a child block for each repetition of the receiving step. ### Claim 13 (depends on 1) The method according to claim 1 wherein the blockchain server is comprised at a service provider. ### Claim 14 (depends on 1) The method according to claim 1 wherein the blockchain server is comprised at a client device. ### Claim 15 (depends on 1) The method according to claim 1 wherein the blockchain server is comprised in a cloud server. ### Claim 16 A system comprising: a blockchain server operative to receive an instruction at a network interface, the instruction being received from a first digital rights management (DRM) client, the instruction comprising an instruction to transfer a DRM license to an encrypted content item to a second DRM client, a blockchain, in which the block chain server is operative to create a block, the block comprising: a content item ID of said encrypted content item; one of a device ID of a device comprising the second DRM client or a user ID of a user of the second DRM client; DRM license information for said DRM license; and a DRM decryption key for decrypting said encrypted content item; wherein the blockchain server is operative to record the block in the blockchain; and the blockchain server is operative to send a confirmation message to the second DRM client confirming that the block was written to the blockchain. ### Claim 17 (depends on 16) The system according to claim 16 wherein the instruction to transfer the DRM license to the second DRM client comprises an instruction to transfer the DRM license for a limited amount of time. ### Claim 18 (depends on 16) The system according to claim 16 wherein the instruction to transfer the DRM license to the second DRM client comprises an instruction to permanently transfer the DRM license. ### Claim 19 (depends on 16) The system according to claim 16 wherein the DRM license comprises a license expiration date. ### Claim 20 A method comprising: receiving a confirmation message at a first DRM client from one of a plurality of blockchain servers when a block is recorded in a blockchain by one of said plurality of blockchain servers, said confirmation message confirming that a DRM license that was legitimately held by a second DRM client has been transferred to said first DRM client, wherein said DRM license comprises a license to an encrypted content item and a decryption key for decrypting the encrypted content item; decrypting the encrypted content item using the decryption key; and consuming the decrypted content item, wherein said block comprises: a content item ID of said encrypted content item; one of a device ID of a device comprising the first DRM client or a user ID of a user of the first DRM client; DRM license information for said DRM license; and said decryption key.