247 results about "Hash chain" patented technology

A method of measuring round trip time (RTT) includes: chain-hashing at least one random number to create a plurality of hash values; (b) transmitting one of the created hash values to a device and starting to measure RTT of the device; and (c) receiving from the device a response to the transmitted hash value and ending the RTT measurement, thereby performing a more effective proximity check than a conventional proximity check requiring encryptions and decryptions of several tens of times through several thousands of times.

A log output device and a program are provided, which append a signature to a log, prevent an undetectable tampering (alteration, insertion, deletion, etc.), and are able to narrow tampered position if tampered. The log output device forms a log record including a data part and a hash part, and outputs to a disk; the hash part is formed by combining a hash of the data part (data hash) and a hash of the hash part of the previous record (link hash); a signature is appended to only a part of records of a hash chain; when outputting the record to the disk, a copy of the hash part of the record is maintained on a process memory; when outputting next record, the hash part of the latest record on the disk and the hash part maintained on the process memory are compared; if they are matched, the record on the disk is determined as not being tampered, and if mismatched, the record is determined as tampered.

A method and apparatus for logging based identification are described. In one embodiment, the method comprises extracting entries of a hash chained log that represents a series of previous transactions. The method may also comprise ordering hash values of the entries extracted from the hash chained log into an ordered list. In one embodiment, the method may further comprise producing a cryptographic hash of the ordered list.

The invention discloses an Internet of Vehicles distributed authentication method based on controllable privacy, relates to the field of vehicle network communication safety, and specifically relates to an Internet of Vehicles distributed authentication method based on controllable privacy. The method specifically includes five following steps: system initialization; private key update of fake names and a part of signatures; message signature; message authentication of signatures; and real identity tracking and revocation. According to the method, the double hash chain is employed to establish the fake names, the communication cost for invalidating a vehicle identity is irrelevant to the numbers of the fake names and a part of the signature private keys of the vehicle, a vehicle user can update multiple parts of signature private keys by the adoption of one authorization, and the burden of trusted authority (TA) and road-side units (RSU) is reduced; when a message with a controversial signature occurs, the TA can distinguish whether the signature is forged by the RSU according to re-signature of the message uploaded by the vehicle, and the problem of non-repudiation in the distributed environment is solved. According to the method, the security is high, the cost is low, and the method is applicable to node high-speed movement, topology structure volatility, and large-scale VANET network.

A method and apparatus for automatically publishing content based identifiers are described. In one embodiment, the method comprises accessing an electronic communication to obtain a content based identifier (CBI) contained in the electronic communication. In one embodiment, the method may also comprise using the CBI to validate integrity of a hash chained log.

The invention relates to a block-chain-based fair data transaction method. The method comprises: step A, a data seller encrypts each piece of data by using different secret keys; step B, a data buyer buys one or more secret keys each time by using a Hash chain micro-payment technique to decrypt corresponding data and carry out verification, and repeated multi-times exchange is carried out until the transaction is completed; and step C, the data seller uses an obtained latest hash value to delock data purchasing expenses trusted at a block chain to obtain deserved data purchasing expenses and the remaining sum is returned to the data buyer in a forced manner. Therefore, on the basis of combination of block-chain-based encrypted currency with the hash chain micro payment technique, a fair data transaction is realized. Moreover, with the method, a problem that the lots of data bought by one time do not meet the requirement can be solved.

The invention provides methods, apparatuses and methods for protecting and verifying data integrity. A method for protecting data integrity comprises the following steps of: dividing data into a plurality of data blocks; calculating the hash value of each data block by means of a first hash function, thereby obtaining a plurality of block hash values and forming a first hash chain; calculating a second hash chain by means of a second hash function according to the first hash chain, wherein the second hash chain comprises a plurality of chain hash values; each chain hash value is associated with the corresponding block hash value in the first hash chain, and associated with the adjacent chain hash value in the second hash chain, and wherein the first hash chain and the second hash chain serve as the integrity information of the data; and generating the verification information of the data by means of the last chain hash value in the second hash chain.

An actor node according to the present invention includes a dynamic change unit for temporarily changing a coverage block in which data are obtained from a sensor node and temporarily causing another actor node to obtain, on behalf of the actor node, data from the sensor node arranged in a partial region of at least a portion of the coverage blocks. The dynamic change unit obtains identification information unique to the another actor node from the another actor node. The dynamic change unit notifies, to the sensor node arranged in the partial region, the obtained identification information. The dynamic change unit notifies, to the another actor node, a portion of the hash chain and a temporary key generated using the obtained identification information and the key used for communication with the sensor node arranged in the partial region.

In an embodiment, content may be encrypted by a first device using a dual hash chain technique, where the first device maintains a forward hash chain and a second device maintains a backward hash chain, and content keys for encrypting content are derived using values of the forward and backward hash chains. The second device may not have knowledge of a seed used to generate the forward hash chain, and therefore may be unable to generate the content keys, reducing a likelihood that the encrypted content becomes compromised. Additionally, embodiments provide for techniques for using proxy re-encryption (PRE) to re-encrypt content, such that the encrypted content may be provided to and decrypted by a requesting device without knowledge of the forward and backward hash chains. Additionally, embodiments provide techniques for distributing encrypted content to a requesting device with fine-grained access control.

The invention discloses a consistent hash based structural data storage, inquiry and migration method. The method comprises steps as follows: a consistent hash based HDFS (hadoop distributed file system) data storage model is established, data storage and data inquiry are performed on the basis of the model, and data migration is performed when a data node is added or fails; the data storage method is as follows: data blocks to be written into a file are subjected to consistent hash, Hash values of the data block are acquired, storage nodes of the data blocks are looked up in a node Hash chain according to the Hash values of the data blocks, and content of the data blocks is stored into the storage nodes of the data blocks. According to the method, on the basis of principal and subordinate structures of a HDFS cluster, structural data are uniformly dispersed onto the data nodes of the HDFS cluster by applying consistent hash, the data parallel traversing efficiency is effectively improved, when the number of data nodes changes, the number of nodes related to data migration and the total migration data amount can be greatly reduced, and the operating performance of the data storage system is improved.

The invention discloses a universal authentication method for terminal equipment without identity in Internet-of-things, which is used for assisting the terminal equipment by introducing edge equipment, and delegates the authentication task to the edge equipment. The method includes a registration period, a session key generation phase, an instruction generation phase and an instruction verification and execution phase. The invention only according to the random identity of the terminal equipment, does not disclose any basic attribute thereof, protects the identity information of the equipmentwell, and realizes the function of privacy protection. Considering the limitation of computing power of Internet of Things devices, a lightweight authentication protocol based on hash chain technology is proposed for non-identifiable terminals.

The invention discloses a partitioned type dynamic safety routing method of a wireless sensor network on the basis of hash chains, which belongs to the field of the computer communication network. According to the partitioned type dynamic safety routing method, a region concept is introduced according to characteristics of clustered routing algorithms and cycle circulation in the wireless sensor network, and a control message is broadcast to the entire network from converging nodes. The region of each node is determined according to the received signal strength, and direct communication among the nodes with larger distance can be avoided by the limitation of the region. After each cycle of cluster head is selected, q link keys are selected from a key pond composed of the hash chains by the node of each cluster head at random, and mutual communicating secret keys are derived according to oneway hash functions and fake random functions used for the chain keys by the other nodes so as to reduce the network communication load. According to the invention, the survival time of the network can be prolonged, the energy consumption of the nodes of the network is better balanced, the safety of the protocol is enhanced, the distribution of the nodes is made to be uniform, and the scope of networks where the protocol is applicable is enlarged.

A rapid-switching method in wireless local-area network includes the following steps: step 1, a wireless workstation sends a second element of a pre-constructed one-way hash chain table to a target wireless access point; step 2, whether the second element is effective or not is judged; if the second element is effective, step 3 is executed, otherwise the process is finished; step 3, connection between the target wireless access point and the wireless workstation is established. The rapid-switching method in wireless local-area network comprises a wireless access point, an authentication service unit, and a wireless workstation; the wireless workstation comprises a first communication module, which is connected with the wireless access point and the authentication service unit; the wireless access point comprises a second communication module, which is connected with the authentication service unit; a memory module, which is connected with the second communication module; an authentication module, which is connected with the memory module and the second communication module; the authentication service unit comprises a third communication module, which is connected with the wireless workstation and the wireless access point. The invention can realize one-way and/or two-way authentication between the wireless workstation and the wireless access point.

The invention relates to the technical field of blockchain security, in particular to a method and device for sending and verifying cross-chain communication data. According to the scheme, hash operation is carried out on cross-chain transaction data to form a current hash chain node related to the front and back of a hash chain node; and the cross-chain transaction data and the hash value of thecurrent hash chain node are sent to a target block chain, operation is carried out on the cross-chain transaction data by using the same hash operation method in the target block chain, and a calculation result is compared with the hash value of the current hash chain node so as to verify the cross-chain communication data. The security of communication between a side chain and a main chain can beimproved.

A method and apparatus are provided for simply and securely limiting a number of times that contents can be accessed using a hash chain. The apparatus limiting a number of times contents are accessed by a user terminal includes a hash chain generator receiving information indicating selected contents by the user terminal and information indicating how many times (n) the user terminal has authority to access the selected contents and generating a hash chain including n hash values derived from a seed value, and a contents access manager deleting the hash values one by one from the hash chain whenever the user terminal accesses the selected contents such that the number of times the contents can be accessed by the user terminal is decreased by the number of deleted hash values.

A method and system for renewing software at the component-level is provided. A client program includes a base component for loading a software component into at least one loadable region of the program to update the program. Code in the software component is for writing state data associating the state of the update in storage, upon execution of the software component, and testing the state data to verify condition of the updated program and disallowing rollback and roll-forward attacks, the state data comprising hash chain values. The state data for verifying the correctness of the updated program is entangled with application data used for the program functionality. A server includes: an update pool having a plurality of software updates deployed in each client, and a policy control for monitoring and controlling at least one of: the length of time the client runs until the software update is invoked, a chain of the updates; and the granularity of the update.

The invention relates to a method for securely broadcasting sensitive data in a wireless sensor networks comprising a central device, called trust center, and a plurality of sensor nodes, the trust center being initialized with a cryptographic hash chain and each node being initialized with a node key and the anchor of the trust center hash chain, the method comprising the following steps: the trust center broadcasting a first secure message to the nodes, each node, after reception of the first message, creating a first acknowledgment message, and transmitting it back to the trust center, the trust center checking whether all the nodes have transmitted respective first acknowledgment message, and in case all messages have been received, the trust center securely broadcasting sensitive data in a third message, the nodes checking, based on elements included in the first message, whether sensitive data actually originates from the trust center.