System and method for mutual authentication and secure communications between a postage security device and a meter server

• US 6,192,473 B1
• Filed: 12/24/1996
• Issued: 02/20/2001
• Est. Priority Date: 12/24/1996
• Status: Expired due to Fees

• Current Assignee: Pitney Bowes Incorporated (Böwe Systec AG)
• Original Assignee: Pitney Bowes Incorporated (Böwe Systec AG)
• Inventors: Ryan, Frederick W. Jr., Sisson, Robert W.
• Primary Examiner(s): Swann, Tod R
• Assistant Examiner(s): Callahan, Paul E.
• Application Number:
  US08/773,472
• Time in Patent Office: 1,519 Days
• Field of Search: 380/21, 380/23, 380/30, 380/24, 380/43, 380/44, 380/45, 380/49, 380/277, 380/283, 395/186, 395/187.01, 395/188.01, 395/200.33, 395/200.47, 395/200.48, 395/200.49, 395/200.52, 395/200.57, 395/200.58, 395/200.67, 395/200.8, 902/2, 902/5, 902/22, 902/24, 902/25, 902/29, 369/29, 705/64, 705/67, 705/75, 705/76, 713/200, 713/168, 713/169
• US Class Current: 713/168
• CPC Class Codes: G06F 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06Q 20/3674 involving authentication
• CPC Class Codes: G06Q 20/382 insuring higher security of transaction
• CPC Class Codes: G06Q 20/3821 Electronic credentials
• CPC Class Codes: G06Q 20/401 Transaction verification
• CPC Class Codes: G07B 17/00024 Physical or organizational aspects of franking systems
• CPC Class Codes: G07B 17/00733 Cryptography or similar special procedures in a franking system
• CPC Class Codes: G07B 2017/00056 Client-server
• CPC Class Codes: G07B 2017/00145 via the Internet
• CPC Class Codes: G07B 2017/00201 Open franking system, i.e. the printer is not dedicated to franking only, e.g. PC (Personal Computer)
• CPC Class Codes: G07B 2017/00766 Digital signature, e.g. DSA, DSS, ECDSA, ESIGN
• CPC Class Codes: G07B 2017/00846 Key management
• CPC Class Codes: G07B 2017/00879 using session key
• CPC Class Codes: G07B 2017/00967 PSD [Postal Security Device] as defined by the USPS [US Postal Service]

Abstract

A method is provided for establishing mutual authentication and secure communications between an microprocessor-based transaction evidencing device and a microprocessor-based server coupled thereto. A session key K_S is generated at the transaction evidencing device and encrypted with a first key K₁ to form a first message. The first message is sent to the server and decrypted using a second key K₂. In response to the first message a second message is generated at the server and encrypted using the session key K_S. The encrypted second message is sent to the transaction evidencing device and decrypted using the session key K_S. A response to the second message is generated at the transaction evidencing device and is signed using a third key K₃. The signed response is encrypted with the session key K_S and transmitted to the server. The encrypted signed response is decrypted using the session key K_S and the signature is verified using a fourth key k₄.

Claims

1. An postage evidencing system, comprising:

a PC meter, including a host computer system and a postal security device;

a meter server operatively coupled to the PC meter, wherein said PC meter and said meter server establish a session key for each transaction completed therebetween;

a data center operatively coupled to the postage metering system, said data center performing certain administrative functions following mutual authentication of said PC meter and said meter server;

a database operatively coupled to said meter server, said database having stored therein second and fourth keys corresponding to first and third keys stored in said PC meter, wherein one of said second and fourth keys is used to decrypt messages encrypted by said PC meter using one of said first and third keys, and the other of said second and fourth keys is used to verify signatures of messages that have been signed by said PC meter using the other of said first and third keys wherein said mutual authentication is completed successful decryption of a first message received from said PC meter and successful verification of a signature on a third message received from said PC meter in response to an encrypted second message sent to said PC meter from said meter server.

2. The system of claim 1 wherein said first message includes said session key, said second message is a response to said first message encrypted with said session key, and said third message is an audit response by said postal security device.

3. The system of claim 1 wherein said first key is identical to said second key.

4. The system of claim 1 wherein said third key is identical to said fourth key.