# US 8,751,821 B2 · Secure read-write storage device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,751,821 B2 - Document ID: US8751821B2 - Status: Granted - Kind: B2 - Application number: 13/774,578 - Filed: 2013-02-22 - Published: 2013-07-04 - Granted: 2014-06-10 - Earliest claimed: 2005-11-14 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Itsik Mantin; Perry Smith; Yaron Sella; Erez Waisbard - Web page: https://patentgrep.com/patent/US8751821B2 ## CPC - G06F 21/6218: {to a system of files or objects, e.g. local or distributed file system or database} - G06F 21/55: Detecting local intrusion or implementing counter-measures - G06F 21/554: {involving event detection and direct action} - G06F 21/575: {Secure boot} - G06F 21/62: Protecting access to data via a platform, e.g. using keys or access control rules - G06F 21/78: to assure secure storage of data (address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00) - H04L 9/0894: {Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage} - H04L 9/30: Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy - G06F 2221/2143: Clearing memory, e.g. to prevent the data from being stolen - G11B 20/00086: {Circuits for prevention of unauthorised reproduction or copying, e.g. piracy (indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00)} - G11B 20/00666: {involving a step of erasing or nullifying data, e.g. data being overwritten with a random string} - G11B 20/00826: {wherein a spoiler signal is added to degrade the signal quality} - H04N 9/8205: {involving the multiplexing of an additional signal and the colour video signal} - 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) - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A method and system for securing a read write storage (RWS) device, the method comprising, providing the RWS device, the RWS device comprising a controller comprising a processor and a bit bucket storing data, and employing the controller to corrupt at least a portion of the data. ## Claims ### Claim 1 A method for securing a read write storage (RWS) device, the method comprising: determining that there is evidence of an attack on the RWS device; employing a sanction, wherein the employing is performed by a controller on the RWS device and the employing comprises at least corrupting a portion of data on the RWS device, wherein the corruption of the corrupted portion of data is reversible by an authorized server; forwarding logging information regarding the corrupted portion of data to the authorized server for analysis; subsequent to a determination by the authorized server in accordance with at least the results of the analysis that the RWS device may resume functioning normally, receiving a private key needed to reverse the corruption from the authorized server; and using the received private key to reverse the corruption of the corrupted portion of data. ### Claim 2 (depends on 1) The method according to claim 1 and wherein the determining comprises: authenticating a boot code by a secure bootloader, wherein the secure bootloader is implemented in a boot area on the RWS device; and based at least on the authenticating, determining if there is evidence of an attack on the RWS device. ### Claim 3 (depends on 1) The method according to claim 1 and wherein the portion of the data which is corrupted comprises control data. ### Claim 4 (depends on 3) The method according to claim 3 and wherein the control data comprises at least one of: keys; mapping tables; or configuration data. ### Claim 5 (depends on 1) The method according to claim 1 and wherein the authorized server comprises a broadcast headend. ### Claim 6 (depends on 1) The method according to claim 1 and wherein the employing a sanction comprises at least one of: the controller resetting; and any other part of the RWS device resetting. ### Claim 7 (depends on 1) The method according to claim 1 and wherein the employing a sanction comprises at least one of: the controller turning itself off; and any other part of the RWS device turning itself off. ### Claim 8 (depends on 1) The method according to claim 1 and wherein the employing a sanction also comprises all or part of the RWS device entering an infinite loop. ### Claim 9 (depends on 1) The method according to claim 1, wherein the RWS device also comprises a plurality of counters. ### Claim 10 (depends on 9) The method according to claim 9 and wherein the plurality of counters comprises positive counters and negative counters. ### Claim 11 (depends on 10) The method according to claim 10 and wherein the positive counters comprise: counters which count successful authentications of code; and counters which count receiving authenticated new versions of software. ### Claim 12 (depends on 10) The method according to claim 10 and wherein the negative counters count events which increase suspicion of an attack on the device. ### Claim 13 (depends on 10) The method according to claim 10 wherein the positive counters and the negative counters are used in the determining. ### Claim 14 (depends on 1) The method according to claim 1 and wherein the employing a sanction comprises disguising the portion of the data on the RWS device. ### Claim 15 (depends on 1) The method according to claim 1 and wherein the corrupting comprises at least one of: erasing the portion of the data; and overwriting the portion of the data with other data. ### Claim 16 (depends on 15) The method according to claim 15 and wherein the overwriting the portion of the data with other data comprises overwriting the data with meaningless data. ### Claim 17 (depends on 15) The method according to claim 15 and wherein the overwriting the portion of the data with other data comprises overwriting the data with faulty data. ### Claim 18 (depends on 1) The method according to claim 1 and further comprising implementing the controller on a controller chip attached to a printed circuit board (PCB) using a Ball-Grid-Array method. ### Claim 19 (depends on 18) The method according to claim 18 and further comprising obscuring lines connecting the controller chip to components on the PCB in a lower layer of the PCB. ### Claim 20 (depends on 1) The method according to claim 1 and wherein the verifying is performed by a security processor and the NVM is appended to the security processor. ### Claim 21 (depends on 20) The method according to claim 20 and further comprising: storing secret keys in appended NVM verifying the integrity of code stored on the RWS device in RAM or the NVM, wherein the verifying comprises using at least one of: a cyclic redundancy check (CRC), a digital signature or a message authentication code to authenticate authentication data appended to the stored code; and employing the sanction in response to at least the results of the verifying. ### Claim 22 (depends on 21) The method according to claim 21 and wherein the verifying is performed at least one of: prior to code execution, during the code execution, or at periodic intervals. ### Claim 23 (depends on 22) The method according to claim 22 and wherein the security processor is comprised in the controller. ### Claim 24 (depends on 21) The method according to claim 21 and wherein the verifying is performed by a security processor comprised in a main processor that is separate from the controller. ### Claim 25 (depends on 1) The method according to claim 1 the method further comprising: providing the RWS with additional storage components, the additional storage components being operative for storage and processing of additional data; and encrypting the additional data stored in the additional storage components. ### Claim 26 (depends on 25) The method according to claim 25 and wherein the additional storage components comprise a RAM buffer for storing and processing the additional data. ### Claim 27 (depends on 25) The method according to claim 25 and also comprising appending an authentication code to the additional data that is stored in the additional storage components. ### Claim 28 A secure RWS device comprising: a sanction logging module configured to log information regarding corrupted data on the RWS device; and a controller configured to: determine if there is evidence of an attack on the RWS device, if there is evidence of an attack on the RWS device, employ a sanction, wherein the sanction is at least corrupting a portion of data on the RWS device, wherein the corruption of the corrupted portion of data is reversible by an authorized server, forward logging information regarding the corrupted portion of data to the authorized server for analysis, subsequent to a determination by the authorized server in accordance with at least the results of the analysis that the RWS device may resume functioning normally, receive a private key needed to reverse the corruption from the authorized server, and reverse the corruption of the corrupted portion of data with the private key. ### Claim 29 (depends on 28) The secure RWS device according to claim 28 and also comprising a security processor configured to verify the integrity of code stored on the RWS device in RAM or NVM, wherein the integrity of the code is verified using at least one of: a cyclic redundancy check (CRC), a digital signature or a message authentication code to authenticate authentication data appended to the stored code. ### Claim 30 A secure RWS device comprising: a sanction logging module configured to log information regarding corrupted data on the RWS device; and a controller chip attached to a PCB in a Ball-Grid-Array configuration, wherein lines connecting the controller chip components on the PCB are obscured in a lower layer of the PCB, and the controller is configured to: determine if there is evidence of an attack on the RWS device, if there is evidence of an attack on the RWS device, employ a sanction, wherein the sanction is at least corrupting a portion of data on the RWS device, wherein the corruption of the corrupted portion of data is reversible by an authorized server, forward logging information regarding the corrupted portion of data to the authorized server for analysis, subsequent to a determination by the authorized server in accordance with at least the results of the analysis that the RWS device may resume functioning normally, receive a private key needed to reverse the corruption from the authorized server, and reverse the corruption of the corrupted portion of data with the private key. ### Claim 31 (depends on 30) The secure RWS device according to claim 30 and also comprising a security processor configured to verify the integrity of code stored on the RWS device in RAM or NVM, wherein the integrity of the code is verified using at least one of: a cyclic redundancy check (CRC), a digital signature or a message authentication code to authenticate authentication data appended to the stored code.