Wave Systems, Inc.

Wave System Corp.

Gregory J Kazmierczak

John R Michener

Kathryn M Smith

Steven K Sprague

A universally available, public cryptographic control unit (crypto unit) is used in a cryptographic system shared by multiple independent users. The crypto unit, which is installed as a peripheral device to a general-purpose computer, loads and unloads encrypted security applets into an onboard RAM memory of the crypto unit, where each security applet is run. The crypto unit and the system of which it is a part, provides a secure internal environment in which only pre-approved security applets are granted permission to load and run. The computing environment within the crypto unit is secured by a cryptographic operation center (OPC) which communicates with each crypto unit. The software developer submits a proposed security applet to the OPC prior to distributing a given security applet in order to obtain the necessary permission for the given security applet. Only if all necessary permissions are obtained from the OPC will a given security applet be allowed to load and run in the crypto unit. When a first security applet is finished running, the crypto unit unloads (swaps out) the presently loaded first security applet in encrypted form to the PC hard drive, and loads (swaps in) the next security applet. The cryptographic context of each security applet is preserved in the file stored on the PC hard drive. In such manner, a single crypto unit is shared among a plurality of independent users.

Public cryptographic control unit and system therefor

The disclosed system relates to metered use cryptographic systems, and particularly to a data package and system operation for effecting metered purchases of encrypted data from a local encrypted database. A local CD ROM encrypted database includes one or more data package records containing one or more message keys encrypted under a database key, and one or more data packages encrypted under said message keys. The user decrypts portions of the database, and the data used is metered locally and recorded as a stored data usage record. The local stored data usage record is reported by telephone modem or other telecommunications link from a remote user terminal, such as a host personal computer containing a remote cryptographic control unit, to a cryptographic operations center. A second embodiment of an encrypted database for use in accordance with the present invention includes a header containing a message key encrypted under said database key, one or more subunit message keys encrypted under said message key, and a subunit data package encrypted under each said subunit message key. The subunit message key is selected to save storage space. The present system further permits a remote transaction mode in which an on line purchase of data from the encrypted database is affected in real time. Flexible system mechanisms include controls over purchase price, start times and expiration times, permission to purchase data on line and off line, and a time window within which purchased data may be decrypted.

Encrypted data package record for use in remote transaction metered data

A cryptographic communications system includes a method and apparatus for sending and receiving a plurality of encrypted signal packets in a system for metering the use of encrypted information. Plural packet communication between a user terminal containing a remote cryptographic control unit and a cryptographic operations center typically includes uploading usage records and downloading credit. Plural packet messages are protected to detect alterations in the form of packet reordering by cross linking data cryptographic codes and message authentication codes (MAC). In particular, a first cryptographic code key is used to encrypt a first plurality of signal packets. A second cryptographic code key is used to encrypt the encrypted first plurality of signal packets to form an appended MAC. The initial vector for computing the MAC for a given packet is the last encrypted data block of the previous packet encrypted with the first cryptographic code key. In such manner, each MAC is a function of the present packet and all previous packets, thereby providing an increased level of security against signal tampering by reordering of packets.

Growing community of inventors

Plainsboro, NJ, United States of America

Gregory J Kazmierczak