Patent ID: 11930123
Assignee: UNIVERSITY OF SAO PAULO
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 19:
20. In an environment where a device, which is one of a plurality of entities, can communicate with one or more other entities through the exchange of messages, each message verifiable with a respective certificate, the system comprising:
a first entity operable to receive a certificate request originating from the device, the certificate request including a caterpillar key, wherein the first entity operable to expand the caterpillar key to generate a plurality of cocoon keys; and
a second entity operable to receive the plurality of cocoon keys, wherein for each cocoon key the second entity operable to generate both a respective signature key and a respective encryption key according to the same expansion function, each encryption key for encrypting a respective certificate, wherein the second entity operable to generate one or more encrypted certificate responses, each encrypted certificate response comprises a respective certificate and is encrypted using a respective encryption key, wherein the second entity operable to transmit the one or more encrypted certificate responses for delivery to the device from which the certificate request originated;
wherein the device is capable of decrypting each encrypted certificate response using an associated decryption key to recover the respective certificate.