A personal digital ID device provides a digital identifier to a service for a predetermined duration in response to user interaction. The user interaction may include a button press. The personal digital ID device may be in the form of a bracelet, a key fob, or other form factor. The service may be provided by a mobile device, in the cloud, or elsewhere.

A cryptographic key management service receives a request, associated with a principal, to use a cryptographic key to perform a cryptographic operation. In response to the request, the service determines whether a rate limit specific to the principal is associated with the cryptographic key. If the rate limit is associated with the cryptographic key, the service generates a response to the request that conforms to the rate limit. The service provides the response in response to the request.

An authentication system receives authentication information from a user as part of a request to access a web-based service. The authentication system transmits the authentication information to a set of second users authorized to evaluate the authentication information. If a threshold number of the set of second users authenticate the identity of the first user, the authentication system enables the user to access the web-based service.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for establishing a proof of storage over a specified period of time. One of the methods includes: (i) receiving, at a prover, an initial input challenge; (ii) producing, at the prover, an output proof proving that the prover has access to specified data for a specified time, wherein producing the output proof includes: (a) producing, at the prover, an initial proof responsive to the initial input challenge, the initial proof proving that the prover is storing specified data; (b) generating, at the prover, a new input challenge based at least in part on the initial proof: (c) producing, at the prover, a new proof responsive to the new input challenge, the new proof proving that the prover is storing the specified data; and (d) repeating, at the prover, the generating step and the producing a new proof responsive to the new input challenge step a number of times, the repeating step generating sequential proofs of storage to determine time of storage , wherein each generating step is based at least in part on a most recent new proof; and (iii) forwarding the output proof, e.g., to a blockchain.

A method of unlocking a second device using a first device is disclosed. The method can include: the first device pairing with the second device; establishing a trusted relationship with the second device; authenticating the first device using a device key; receiving a secret key from the second device; receiving a user input from an input/output device; and transmitting the received secret key to the second device to unlock the second device in response to receiving the user input, wherein establishing a trusted relationship with the second device comprises using a key generated from a hardware key associated with the first device to authenticate the device key.

An integrated circuit includes: one or more protected circuits; a license control circuit configured to request, from a license issuer, a license for activating the one or more protected circuits, the license request having a seed value; and a cryptographic circuit configured to verify the authenticity of a license received from the license issuer based on the seed value, wherein the license control circuit is configured to impose a validity limit on the received license, and to request a new license from the license issuer before the validity limit of the received license.

A method of authenticating a consumable or detachable element of a continuous inkjet printer comprising: the controller of the printer generating a 1.sup.st item of random information that is dispatched to an authentication circuit of the element; encrypting the 1.sup.st item of information by the authentication circuit using a 1.sup.st encryption algorithm and a 1.sup.st secret key to form a 1.sup.st item of encrypted random information; dispatching the 1.sup.st item of information to the controller; encrypting the 1.sup.st item of information by the controller using a 2.sup.nd encryption algorithm and a 2.sup.nd secret key to form a 2.sup.nd item of encrypted random information; comparing the 1.sup.st item of encrypted random information with the 2.sup.nd encrypted item of random information to authenticate the consumable element; and if the consumable element is authenticated, dispatching at least one part of a 3.sup.rd key, termed the shared key, by the element to the printer.

An administered authentication system can authenticate an artificial reality device using an authorization record between a user account and an artificial reality device. In some implementations, the authorization record is created in response to activation of a user account-specific key sent to a user-supplied contact, where an artificial reality device identifier was provided with the user-supplied contact. In other implementations, the authorization record is created in response to activation of a user account-specific key provided to the artificial reality device as a code, where activation of the key includes adding an artificial reality device identifier to a key activation message. In yet other implementations, the authorization record is created in response to an application associated with a user account activating an artificial reality device-specific key, with an artificial reality device identifier, that is provided via the artificial reality device.

Visually enrolling a camera using an optical code and a picture file, including: receiving the picture file and the optical code from the camera, wherein the optical code includes a public key of the camera; generating a visual challenge using a nonce created by a random number generator; transmitting the visual challenge to a user of the camera to capture the visual challenge; receiving the captured visual challenge from the camera; extracting a response from the captured visual challenge; comparing the response to the nonce to verify a signature of the captured visual challenge using the public key of the camera and to convert the optical code received from the camera into a valid certificate; and enrolling the camera and adding the valid certificate to a key store.

The present invention relates to a communication node, a method of operating the same, and a collaborative system. In an example of the present invention, there may be provided an operation method of a first communication node (a transmission node) comprising: a step of confirming whether data is to be transmitted to the receiving side communication node by a transmitting side communication node among communication nodes connected to each other on the network; a step for generating first control information for verifying authentication and integrity of the data; a step for generating a first control information including information for authenticating and verifying integrity of the data to be transmitted by the transmitting side communication node; a step for sharing the first control information with at least one or more participating communication nodes including the receiving side communication node through a channel formed in a block chain network; and a step for transmitting a message including the data through a channel formed in a network different from the block chain network.