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NIST Proposes Voluntary Federal Standard for Key Escrow Encryption

The National Institute of Standards and Technology announced today a proposed voluntary escrowed encryption standard that will help improve the security and privacy of telephone communications while meeting law enforcement needs.  

The standard specifies use of the SKIPJACK cryptographic algorithm and a method for creating a Law Enforcement Access Field, or LEAF.  The LEAF provides a mechanism needed for authorized government agencies to decipher lawfully intercepted encrypted telecommunications.  

The standard, which covers voice, fax and low-speed data, may be used by federal agencies and others in designing and implementing security products and systems to encrypt sensitive but unclassified data.  Specific operations of the algorithm and the LEAF creation method are classified; they are referenced, but not specified, in the standard.

The standard is part of a voluntary key escrow encryption program announced by the White House on April 16.  Both the algorithm and the LEAF method are to be implanted on an electronic chip and used in new, relatively inexpensive encryption devices that attach to telephones.  Two separate key escrow agents will retain the two different key components needed to decode messages.  Only government officials with legal authorization to conduct a wiretap will be provided access to both key components.

The announcement by NIST and information concerning the applicability, implementation and technical aspects of the standard will appear in the July 30 Federal Register.  Written comments on this proposed standard are due Sept. 28, 1993.  They should be sent to Director, Computer Systems Laboratory, Attn:  Proposed FIPS for Escrowed Encryption Standard, B154 Technology Building, NIST, Gaithersburg, Md. 20899-0001. 

The Computer Security Act of 1987 establishes NIST responsibility for developing standards and guidelines needed to protect the security and privacy of unclassified information in federal computer systems.

The National Institute of Standards and Technology is the only federal technology agency with the primary mission of helping U.S. industry to strengthen its competitiveness.  NIST assists industry in developing, adapting and commercializing technologies which lead to greater productivity, higher quality, and new and improved products and services.  NIST is an agency of the U.S. Commerce Department's Technology Administration. 

Released July 29, 1993, Updated November 27, 2017