Offline bidirectional transaction and secure system

A computer program product comprising:

• one or more computer readable storage media, and program instructions collectively stored on the one or more computer readable storage media, the program instructions comprising:
• program instructions to register, by a backend server, a user and a second device associated with the user for an offline transaction privilege of the user associated with a user identifier, by generating a public certificate of the user and sharing the public certificate with a first device;
• program instructions to store a user certificate associated with the user identifier in a local repository of the first device;
• program instructions to receive, by the first device, a request from the registered user associated with the registered second device;
• send, by the first device, information in an optically recognizable first code including an identity of the first device and a type of optical reader associated with the first device;
• generating, by the second device, encoded information in an optically recognizable second code generated using information including the optically recognizable first code, a one-time password seed, and the type of optical reader associated with the first device, and further the optically recognizable second code being generated using the information including an identity of the second device, the user certificate associated with the user identifier, and a one-time password generated using a private key of the registered second device and the one-time password based on the one-time password seed;
• program instructions to receive at the first device, the optically recognizable second code;
• program instructions to, to decode the encoded information in the optically recognizable second code, the decoding including extracting, by a transaction module of the first device, the user identifier and the one-time password associated with the registered second device;
• program instructions to, in response to a determination the backend server is unreachable for electronic communication by the transaction module of the first device, determine that a user certificate exists in the local repository of the first device;
• program instructions to validate by the transaction module of the first device, the one-time password associated with the registered second device with the user certificate using the public certificate associated with the first device, the one-time password associated with the registered second device and the one-time password seed;
• and
• program instructions to authenticate, using the transaction module, the user.

A computer system comprising:

• one or more computer processors, one or more computer readable storage media, and program instructions stored on the one or more computer readable storage media for execution by at least one of the one or more computer processors, the program instructions comprising:
• program instructions to register, by a backend server, a user and a second device associated with the user for an offline transaction privilege of the user associated with a user identifier, by generating a public certificate of the user and sharing the public certificate with a first device;
• program instructions to store a user certificate associated with the user identifier in a local repository of the first device;
• program instructions to receive, by the first device, a request from the registered user associated with the registered second device;
• send, by the first device, information in an optically recognizable first code including an identity of the first device and a type of optical reader associated with the first device;
• generate, by the second device, encoded information in an optically recognizable second code generated using information including the optically recognizable first code, a one-time password seed, and the type of optical reader associated with the first device, and further the optically recognizable second code being generated using the information including an identity of the second device, the user certificate associated with the user identifier, and a one-time password generated using a private key of the registered second device and the one-time password based on the one-time password seed;
• program instructions to receive at the first device, the optically recognizable second code;
• program instructions to decode the encoded information in the optically recognizable second code received, the decoding including extracting, by a transaction module of the first device, the user identifier and the one-time password associated with the registered second device;
• program instructions to, in response to a determination the backend server is unreachable for electronic communication by the transaction module of the first device, determine that a user certificate exists in the local repository of the first device;
• program instructions to validate, by the transaction module of the first device, the one-time password associated with the registered second device with the user certificate using the public certificate associated with the first device, the one-time password associated with the registered second device and the one-time password seed;
• and
• program instructions to authenticate, using the transaction module, the user.