voton TSA service is an authoritative third-party public * * trusted timestamp service that is planned and constructed according to the relevant timestamp technology and service standards at home and abroad and the trusted timestamp service system in China. It can be widely used in various fields such as intellectual property protection, cultural creativity and e-government. The national time service center, the only legal time source in China, is responsible for time traceability, synchronization and monitoring, and the national authority ensures the credibility of the time source.
Function of timestamp
The client is making a request to the server interface. If the request information is encrypted and intercepted by a third party, it can be used for repeated request operations. If the server does not carry out replay attack, the pressure on the server will increase, and the use of timestamp can solve this problem.
tamper-proof: the commonly used method is to splice the parameters, the current item AppKey, and the "key" agreed by both parties, add them into the Dictionary set, sort them in ABCD order, and finally encrypt them in MD5+. The client sends the encrypted string to the server together with the requested parameters. After the server is spliced and encrypted according to the above rules, is it equal to the incoming encrypted string?
Anti-multiplexing: The above encryption method cannot solve the problem of anti-multiplexing. At this time, you need to generate UTC timestamps on the client and the server respectively. This UTC is to prevent your client and the server from being in the same time zone, and then you can put the timestamp in the ciphertext.