A method, a data processing system, and a computer program product for managing cryptographic information. A determination is made as to whether a first time stamp of when cryptographic information was created is more recent than a second time stamp of a backup of the cryptographic information in response to receiving a request for the cryptographic information from a requester. The cryptographic information is used to encrypt data. The cryptographic information is prevented from being provided to the requester in response to a determination that the first time stamp of cryptographic information creation is more recent than the second time stamp of the backup of the cryptographic information.

A streaming one time pad cipher using rotating ports for data encryption uses a One Time Pad (OTP) and an Exclusive Or (XOR) (or other cipher) with a public key channel to encrypt and decrypt OTP data. There is no method in cryptography to thwart the OTP/XOR method and it is proven impossible to crack. The method also rotates the ports of the channels periodically to increase communication obfuscation. Through pre-fetching and cache of OTP data, latency increases from encryption are kept to an absolute minimum as the XOR for encryption and decryption is done with a minimal number of instructions.

The techniques herein are directed generally to personalized secure communication session management, such as for virtual private networks (VPNs). In one embodiment, a user is authenticated at a client device to verify that the user is present at the client device and authorized to access one or more secured resources, and in response, a secure communication session is established for the client device to access the secured resources. At a later time during the secure communication session, it is determined whether the user is still authenticated at the client device, such that if so, access to the one or more secured resources is maintained on the secure communication session, or else access is restricted to the one or more secured resources (e.g., the session is terminated, or access is otherwise limited).

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for using cryptographic techniques to enhance data security and privacy and increase computational efficiency in selecting digital components are described. In one aspect, a method includes receiving, by an MPC computer of a group of MPC computers configured to perform computations of a secure MPC protocol to select digital components for distribution to client devices, a first secret share of location information indicating a location of a client device. The MPC computer generates, by performing the computations of the secure MPC protocol in collaboration with one or more second computers of the group of MPC computers, a first secret share of a selection result including data identifying a selected digital component that is selected from candidate digital components that are candidates based at least in part on the location of the client device.