CA2146024A1 - Method and Apparatus for Providing Cryptographic Protection of a Data Stream in a Communication System - Google Patents

Method and Apparatus for Providing Cryptographic Protection of a Data Stream in a Communication System

Info

Publication number
CA2146024A1
CA2146024A1 CA2146024A CA2146024A CA2146024A1 CA 2146024 A1 CA2146024 A1 CA 2146024A1 CA 2146024 A CA2146024 A CA 2146024A CA 2146024 A CA2146024 A CA 2146024A CA 2146024 A1 CA2146024 A1 CA 2146024A1
Authority
CA
Canada
Prior art keywords
sequence number
packet
data stream
cryptographic protection
communication system
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2146024A
Other languages
French (fr)
Other versions
CA2146024C (en
Inventor
Louis David Finkelstein
James Joseph Kosmach
Jeffrey Charles Smolinske
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Motorola Mobility LLC
Original Assignee
Louis David Finkelstein
James Joseph Kosmach
Jeffrey Charles Smolinske
Motorola, Inc.
Motorola Mobility, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=22345810&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=CA2146024(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Louis David Finkelstein, James Joseph Kosmach, Jeffrey Charles Smolinske, Motorola, Inc., Motorola Mobility, Inc. filed Critical Louis David Finkelstein
Publication of CA2146024A1 publication Critical patent/CA2146024A1/en
Application granted granted Critical
Publication of CA2146024C publication Critical patent/CA2146024C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/04—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks
    • H04L63/0428—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload
    • H04L63/0457—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload wherein the sending and receiving network entities apply dynamic encryption, e.g. stream encryption
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09C—CIPHERING OR DECIPHERING APPARATUS FOR CRYPTOGRAPHIC OR OTHER PURPOSES INVOLVING THE NEED FOR SECRECY
    • G09C1/00—Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
    • H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
    • H04L1/1607—Details of the supervisory signal
    • H04L1/1642—Formats specially adapted for sequence numbers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/06—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols the encryption apparatus using shift registers or memories for block-wise or stream coding, e.g. DES systems or RC4; Hash functions; Pseudorandom sequence generators
    • H04L9/065—Encryption by serially and continuously modifying data stream elements, e.g. stream cipher systems, RC4, SEAL or A5/3
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/40—Network security protocols

Abstract

A method and apparatus for providing cryptographic protection of a data stream are described in accordance with the Open Systems Interconnection (OSI) model for a communication system. This cryptographic protection is accomplished on the transmitting side by assigning a packet sequence number to a packet derived from a data stream received from a network layer (110). Subsequently, a transmit overflow sequence number (124) is updated as a function of the packet sequence number (116). Then, prior to communicating the packet and the packet sequence number on a physical layer, the packet is encrypted as a function of the packet sequence number (116) and the transmit overflow sequence number (124). On the receiving side, the packet sequence number is extracted (166) from the physical layer (160). In addition, a receive overflow sequence number (174) is updated as a function of the packet sequence number (172). Finally, the encrypted packet is decrypted as a function of the packet sequence number (176) and the receive overflow sequence number (178). In addition, a transmitting and a receiving communication unit for use in a communication system which includes cryptographic protection of a data stream is described.
CA002146024A 1993-08-26 1994-07-11 Method and apparatus for providing cryptographic protection of a data stream in a communication system Expired - Lifetime CA2146024C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US112,780 1993-08-26
US08/112,780 US5319712A (en) 1993-08-26 1993-08-26 Method and apparatus for providing cryptographic protection of a data stream in a communication system

Publications (2)

Publication Number Publication Date
CA2146024A1 true CA2146024A1 (en) 1995-03-02
CA2146024C CA2146024C (en) 1998-09-22

Family

ID=22345810

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002146024A Expired - Lifetime CA2146024C (en) 1993-08-26 1994-07-11 Method and apparatus for providing cryptographic protection of a data stream in a communication system

Country Status (7)

Country Link
US (1) US5319712A (en)
EP (1) EP0671092B1 (en)
JP (1) JP3983281B2 (en)
KR (2) KR0145494B1 (en)
CA (1) CA2146024C (en)
FI (1) FI115016B (en)
WO (1) WO1995006374A1 (en)

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Also Published As

Publication number Publication date
EP0671092A1 (en) 1995-09-13
EP0671092B1 (en) 2000-09-27
KR0145494B1 (en) 1998-08-01
WO1995006374A1 (en) 1995-03-02
JPH08503113A (en) 1996-04-02
CA2146024C (en) 1998-09-22
FI951945A0 (en) 1995-04-25
KR950704882A (en) 1995-11-20
FI115016B (en) 2005-02-15
JP3983281B2 (en) 2007-09-26
EP0671092A4 (en) 1995-12-13
US5319712A (en) 1994-06-07
FI951945A (en) 1995-04-25

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