Patent ID: 7635084

Claim:
In a portable electronic authorization device (PEAD) with inaccessible storage of a user's private key, a method for approving a transaction request originating from an electronic transaction system which stores or has access to a user's public key, comprising: receiving at said portable electronic authorization device first digital data, said first digital data representing said transaction request and including the user's public key; performing approval and encryption of the transaction approval solely within the PEAD utilizing a private key stored within the PEAD accessed using the user's public key without transmission of the private key to the remote electronic transaction system or entry of the private key by the user to the PEAD; and if said transaction request is approved by a user of said portable electronic authorization device, and transmitting a second digital data to said electronic transaction system, said second digital data being encrypted by said user private key but without transmission of the private key to the transaction approval system at any time during or after the transaction approval.