The HP Protocol for
                     Internet Secure Payment
                         Transactions

                           Wenbo Mao

                   Electronic-Business Project

              Hewlett-Packard Laboratories, Bristol

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Outline

  o  Requirements for the Internet electronic commerce
  
  o  The HP technique

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Requirements for the Internet electronic commerce

  o  Security Requirements

     -  entity authentication (knowing to whom I am talking)

     -  message integrity

     -  non-repudiation on message origin (payment) and message
        receipt (purchase confirmation)

     -  reliability (communication error does not give rise to 
        financial disputes)

  o  Non-Security Requirements

     -  low transaction cost
  
     -  ubiquitous technology

     -  scalability

     -  high capacity of financial services

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The HP's Technique

  o  rational use of public keys: for non-repudiation service only,
     not for authentication service (a low cost issue: the services 
     for authentication and replay detection are provided by simple
     challenge/response techniques)

  o  a low cost, light-weight public-key certification method:
     financial institutions certify public keys of end-users on-line, 
     at the same time when they provide on-line financial services; 
     the on-line key certification allows the financial bodies to
     fully control the liability of the key certification and provide 
     examinable (auditable) evidence to prove their correctness in 
     certifying the public keys of the end-users

  o  a signature for committing a payment is released only when the
     buyer's has satisfied the result of a protocol run, so the
     possible communication error will not give rise to financial 
     disputes (reliability of the protocol even the communication
     channel, i.e., the Internet, is not reliable)

  o  distribute the entity and message authentication work to the
     end-users, so the financial institutions will have a full
     capacity to provide on-line financial services (e.g., checking
     the credit worthyness of a buyer)

  o  exportability/importability: only use one-way transformation;
     no decryption (for retrieval of secret) is used; no secret will
     be established among principles as a result of a protocol run;
     just like a non-cryptographic coding technique; can be deployed
     in the worldwide area

  o  general in transaction models, either credit or debit methods

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Further Details

  For details of the HP Protocol, see the following URL

    http://www.hpl.hp.co.uk/projects/vishnu/main.html

  or email to: wm@hplb.hpl.hp.com