Implicitly Certified Digital Signatures

A first terminal, comprising:

• at least one hardware processor;
• and
• a non-transitory computer-readable storage medium coupled to the at least one hardware processor and storing programming instructions for execution by the at least one hardware processor, wherein the programming instructions, when executed, cause the at least one hardware processor to perform operations comprising:
• receiving, by the first terminal, a first modified message and a digital signature from a second terminal over a data communication network;
• obtaining, by the first terminal, an unmodified message associated with the first modified message;
• obtaining, by the first terminal, an implicit certificate associated with the second terminal, wherein the implicit certificate includes a public key reconstruction value of the second terminal, the public key reconstruction value of the second terminal is different than a public key of the second terminal, and the public key of the second terminal is reconstructed using the public key reconstruction value of the second terminal and a public key of a certificate authority;
• generating, by the first terminal, a hash value based on the implicit certificate;
• generating, by the first terminal, a second modified message by combining the unmodified message with the hash value and the public key reconstruction value of the second terminal;
• and
• verifying, by the first terminal, the unmodified message based on the digital signature and the second modified message.