US 5850442

Patent Overview: US5850442A

Title: Secure world wide electronic commerce over an open network

Patent Number: US5850442A

Inventor: Sead Muftic

Original Assignee: Entegrity Solutions Corp (current assignee listed as Intellectual Ventures II LLC)

Application Number: US08/622,015

Priority/Filing Date: 1996-03-26

Publication (Grant) Date: 1998-12-15

Legal Status: Expired – Lifetime (anticipated expiration 2016-03-26)

Purpose and Plain-Language Scope

The patent is directed to the field of communication systems, and more particularly to systems using smart tokens—such as smart cards or PCMCIA cards—together with a public key infrastructure to enable secure electronic transactions over an open network.

The excerpt explains the underlying concepts the invention builds upon. Encryption is used both to ensure privacy (so only the intended recipient can decrypt information) and to ensure authenticity (that a message genuinely originated with its purported source and was not tampered with). In single-key encryption, one shared key both encrypts and decrypts, but the key must be available to both sender and receiver, which is inconvenient and insecure. In public key systems, each participant has a public key and a related private key; material encrypted with the public key can only be decrypted with the private key, and material encrypted with the private key can only be decrypted with the public key. Knowledge of the public key does not help deduce the private key, so the public key can be widely disseminated. Sender authentication and electronic signatures can be achieved by encrypting with the signer's private key, and message digests (analogous to CRC check sums) may be used to avoid encrypting entire large documents.

The classification references indicate the subject matter relates to payment architectures, electronic credentials and certificates, key management, electronic wallets, electronic shopping, and electronic negotiation.

Source: https://patents.google.com/patent/[US5850442](/patent/US5850442)/en

What the excerpt does not establish: The supplied text is an abbreviated excerpt. It does not include the full claims, the complete written description, detailed embodiments, or the specific figures. It also does not establish the precise claimed scope, the specific smart-token mechanisms, or the exact manner in which the public key infrastructure is integrated. No prior art or validity analysis is presented here.