Abstract: In a computer based system and method for on-line payment, a transaction is completed between a shopper and a merchant using one or two trusted third parties. Both the shopper and merchant may use the same trusted third party or each may use its own trusted third party. A trusted third party receives and sends messages to and from the shopper and merchant as well as a payment center. Each message provides encrypted information on the nature of the transaction. The trusted third party does not have the capability to decrypt detailed transaction information and thus is not privy to the nature of the transaction. Should a dispute arise, all parties involved have sufficient encrypted information in the messages to determine the nature of the transaction and the steps concluded.

Abstract: A mechanism for securing bid proposals until close of tendering is provided for an electronic tendering system over an open network. In order to be permitted to file a bid electronically in response to an invitation to tender, prospective vendors encrypt their bid proposals using session keys obtained from a third party source. The encrypted proposals are filed with the bid requester who does not have access to the session keys while the tendering period remains open. The encrypted bid proposals are cached in a safe repository until close of tendering. In one embodiment, the bid requester itself holds onto the encrypted proposals, and obtain the session keys for accessing their contents from the third party on expiry of the bid submission period. In another embodiment, the bid requester double-encrypts each encrypted bid proposal as it is received using its own privately-held key, and forwards the double-encrypted proposals to the third party to hold in a safe repository until the close of tendering.

Abstract: To reduce the number of key pairs that must be managed in an asymmetric encryption/decryption system, each customer of a vendor is assigned to at least one defined customer group as a function of the information that is to be made available to the customer. A key pair consisting of a group source key and a group member key is assigned to each defined customer group. The vendor uses the group source key to encrypt information to be made available only to members of the associated group. Authenticated customers are given the group member key for each group to which they belong. The customers use the group member key to decrypt information previously encrypted by the vendor using the associated group source key.

Abstract: A generic secure file format to solve problems associated with secure storage and interchange. The file format allows multiple files to be wrapped into a single entity for storage or transmission interchange. Each file can have different security requirements from that of other files. Different file types can be interchanged under a single wrapper in this secure file format. The secure file format also allows one file to be divided into multiple sections and wraps them into a single file. Each section of the file has its own security protection. This enables only sensitive information to be protected, and leaves other sections with less or no security protection. This results in higher performance since security related operations are only required for a small portion of the file.