Cryptographic Algorithms and 

Key Sizes for Personal Identity 

Verification

NIST Special Publication 800-78

W. Timothy Polk 

Donna F. Dodson 

William E. Burr 

I N F O R M A T I O N S E C U R I T Y

Computer Security Division 

Information Technology Laboratory

National Institute of Standards and Technology

Gaithersburg, MD, 20899-8930 

April 2005

U.S. Department of

Carlos M. Gutierrez,

U.S. Department of

Technology

Phillip J. Bond, Under Secretary for 

Technology

Phillip J. Bond, Under Secretary for 

National Institute of Standards and 

Hratc .

National Institute of Standards and 

Hratch G. Semerjian, Acting 
Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

Reports on Computer Systems Technology 

The Information Technology Laboratory (ITL) at the National Institute of Standards and 

Technology (NIST) promotes the U.S. economy and public welfare by providing technical 

leadership for the Nation’s measurement and standards infrastructure. ITL develops tests, test 

methods, reference data, proof of concept implementations, and technical analyses to advance 

the development and productive use of information technology. ITL’s responsibilities include 

the development of management, administrative, technical, and physical standards and 

guidelines for the cost-effective security and privacy of non-national security-related information 

in Federal information systems. This special publication 800-series reports on ITL’s research, 

guidelines, and outreach efforts in information system security, and its collaborative activities 

with industry, government, and academic organizations. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

Table of Contents

1. INTRODUCTION .................................................................................................................... 1 

1.1 AUTHORITY .......................................................................................................................1 

1.2 PURPOSE ............................................................................................................................1 

1.3 SCOPE ................................................................................................................................1 

1.4 AUDIENCE AND ASSUMPTIONS...........................................................................................2 

1.5 DOCUMENT OVERVIEW......................................................................................................2 

2. APPLICATION OF CRYPTOGRAPHY IN FIPS 201............................................................ 3 

3. ON CARD CRYPTOGRAPHIC REQUIREMENTS .............................................................. 5 

3.1 PIV CRYPTOGRAPHIC KEYS ..............................................................................................5 

3.2 AUTHENTICATION INFORMATION STORED ON THE PIV CARD ...........................................7 

3.2.1 Specification of Digital Signatures on Authentication Information ........................... 7

3.2.2 Specification of Public Keys In X.509 Certificates..................................................... 8

3.2.3 Specification of Message Digests in the SP 800-73 Security Object.......................... 9

4. CERTIFICATE STATUS INFORMATION.......................................................................... 11 

5. PIV CARD MANAGEMENT KEYS..................................................................................... 12 

APPENDIX A— ACRONYMS .................................................................................................. 13 

APPENDIX B— REFERENCES.............................................................................................. 14 

List of Tables 

Table 3-1. Algorithm and Key Size Requirements for PIV Key Types ........................................ 6 

Table 3-2. RSA Public Key Exponents.......................................................................................... 7 

Table 3-3. Signature Algorithm and Key Size Requirements for PIV Information ...................... 8 

Table 3-4. FIPS 201 Signature Algorithm Object Identifiers........................................................ 8 

Table 3-5. Public Key Object Identifiers for PIV Key Types........................................................ 9 

Table 3-6. ECC Parameter Object Identifiers for Approved Curves............................................. 9 

Table 3-7. Hash Algorithm Requirements for the 800-73 Security Object ................................. 10 

Table 3-8. Hash Algorithm Object Identifiers for the 800-73 Security Object ........................... 10 

Table 4-1. Signature Algorithm and Key Size Requirements for PIV Status Information.......... 11 

Table 5-1. Algorithm and Key Size Requirements for Card Management Keys ........................ 12 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

1. Introduction

The Homeland Security Presidential Directive (HSPD) 12 mandated the creation of new 

standards for interoperable identity credentials for physical and logical access to Federal 

government locations and systems. Federal Information Processing Standard 201 (FIPS 201), 

Personal Identity Verification (PIV) of Federal Employees and Contractors, was developed to 

establish standards for identity credentials [FIPS201]. This document, Special Publication 800-

78 (SP 800-78), specifies the cryptographic algorithms and key sizes for PIV systems and is a 

companion document to FIPS 201. 

1.1 Authority

This document has been developed by the National Institute of Standards and Technology 

(NIST) in furtherance of its statutory responsibilities under the Federal Information Security 

Management Act (FISMA) of 2002, Public Law 107-347. 

NIST is responsible for developing standards and guidelines, including minimum requirements, 

for providing adequate information security for all agency operations and assets, but such 

standards and guidelines shall not apply to national security systems. This recommendation is 

consistent with the requirements of the Office of Management and Budget (OMB) Circular A130, Section 8b(3), Securing Agency Information Systems, as analyzed in A-130, Appendix IV: 

Analysis of Key Sections. Supplemental information is provided A-130, Appendix III. 

This recommendation has been prepared for use by Federal agencies. It may be used by nongovernmental organizations on a voluntary basis and is not subject to copyright. Nothing in this 

document should be taken to contradict standards and guidelines made mandatory and binding 

on Federal agencies by the Secretary of Commerce under statutory authority. Nor should this 

recommendation be interpreted as altering or superseding the existing authorities of the Secretary 

of Commerce, Director of OMB, or any other Federal official. 

1.2 Purpose 

FIPS 201 defines requirements for the PIV lifecycle activities including identity proofing, 

registration, PIV Card issuance, and PIV Card usage. FIPS 201 also defines the structure of an 

identity credential that includes cryptographic keys. This document contains the technical 

specifications needed for the mandatory and optional cryptographic keys specified in FIPS 201 

as well as the supporting infrastructure specified in FIPS 201 and the related Special Publications 

800-73 (SP 800-73), Interfaces for Personal Identity Verification, and the forthcoming SP 800-

76, Biometric Data Specification for Personal Identity Verification, [SP800-76] that rely on 

cryptographic functions. 

1.3 Scope 

The scope of this recommendation encompasses the PIV Card, infrastructure components that 

support issuance and management of the PIV Card, and applications that rely on the credentials 

supported by the PIV Card to provide security services. The recommendation identifies 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

acceptable symmetric and asymmetric encryption algorithms, digital signature algorithms, and 

message digest algorithms, and specifies mechanisms to identify the algorithms associated with 

PIV keys or digital signatures. 

Algorithms and key sizes have been selected for consistency with applicable Federal standards 

and to ensure adequate cryptographic strength for PIV applications. All cryptographic 

algorithms employed in this specification provide at least 80 bits of security strength. For 

detailed guidance on the strength of cryptographic algorithms, see the forthcoming [SP800-57], 

Recommendation on Key Management. 

1.4 Audience and Assumptions 

This document is targeted at Federal agencies and implementers of PIV systems. Readers are 

assumed to have a working knowledge of cryptography and Public Key Infrastructure (PKI) 

technology. 

1.5 Document Overview 

The document is organized as follows: 

+ Section 1, Introduction, provides the purpose, scope, audience, and assumptions of the 

document and outlines its structure. 

+ Section 2, Applications of Cryptography in FIPS 201, identifies the cryptographic 

mechanisms and objects that employ cryptography as specified in FIPS 201 and its 

supporting documents. 

+ Section 3, On Card Cryptographic Requirements, describes the cryptographic 

requirements for cryptographic keys and authentication information stored on the PIV 

Card. 

+ Section 4, Certificate Status Information, describes the cryptographic requirements for 

status information generated by PKI Certificate Authorities (CAs) and Online Certificate 

Status Protocol (OCSP) responders. 

+ Section 5, PIV Card Management Keys, describes the cryptographic requirements for 

management of information stored on the PIV Card. 

+ Appendix A, Acronyms, contains the list of acronyms used in this document. 

+ Appendix B, References, contains the list of documents used as references by this 

document. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

2. Application of Cryptography in FIPS 201 

FIPS 201 employs cryptographic mechanisms to authenticate cardholders, secure information 

stored on the PIV Card, and secure the supporting infrastructure. 

FIPS 201 and its supporting documents specify a suite of keys to be stored on the PIV Card for 

personal identity verification, digital signature generation, and key management. The PIV 

cryptographic keys specified in FIPS 201 are: 

+ The asymmetric PIV authentication key; 

+ A card authentication key, which may be symmetric or asymmetric; 

+ An asymmetric digital signature key for signing documents and messages; and 

+ An asymmetric key management key, supporting key establishment or key transport. 

The cryptographic algorithms, key sizes, and parameters that may be used for these keys are 

specified in Section 3.1. PIV Cards must implement private key computations for one or more 

of the algorithms identified in this section. 

Cryptographically protected objects specified in FIPS 201, SP 800-73, and the forthcoming SP 

800-76 include: 

+ The X.509 certificates for each asymmetric key on the PIV Card; 

+ A digitally signed Cardholder Unique Identifier (CHUID); 

+ Digitally signed biometrics using the Common Biometric Exchange Formats Framework 

(CBEFF) signature block; and 

+ The SP 800-73 Security Object, which is a digitally signed hash table. [SP800-73] 

The cryptographic algorithms, key sizes, and parameters that may be used to protect these 

objects are specified in Section 3.2. Certificate Authorities (CAs) and card management systems 

that protect these objects must support one or more of the cryptographic algorithms, key sizes, 

and parameters specified in Section 3.2. 

Applications may be designed to use any or all of the cryptographic keys and objects stored on 

the PIV Card to authenticate cardholders. Where maximum interoperability is required, 

applications should support all of the identified algorithms, key sizes, and parameters specified 

in Section 3.2. 

FIPS 201 requires CAs and Online Certificate Status Protocol (OCSP) responders to generate 

and distribute digitally signed Certificate Revocation Lists (CRLs) and OCSP status messages. 

These revocation mechanisms support validation of the PIV Card, the PIV cardholder, the 

cardholder’s digital signature key, and the cardholder’s key management key. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

The signed revocation mechanisms specified in FIPS 201 are: 

+ X.509 CRLs that specify the status of a group of X.509 certificates; and 

+ OCSP status response messages that specify the status of a particular X.509 certificate. 

The cryptographic algorithms and key sizes, and parameters that may be used to sign these 

mechanisms are specified in Section 4. Section 4 also describes rules for encoding the signatures 

to ensure interoperability. 

FIPS 201 permits optional card management operations. These operations may only be

performed after the PIV Card authenticates the card management system. Card management 

systems are authenticated through the use of card management keys. The cryptographic 

algorithms and key sizes that may be used for these keys are specified in Section 5. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

3. On Card Cryptographic Requirements 

FIPS 201 identifies a suite of objects that are stored on the PIV Card for use in authentication 

mechanisms or in other security protocols. These objects may be divided into three classes: 

cryptographic keys, signed authentication information stored on the PIV Card, and message 

digests of information stored on the PIV Card. Cryptographic requirements for PIV keys are 

detailed in Section 3.1. Cryptographic requirements for other stored objects are detailed in 

Section 3.2. 

3.1 PIV Cryptographic Keys

FIPS 201 specifies four different classes of cryptographic keys to be used as credentials by the 

PIV cardholder: 

+ The mandatory PIV authentication key; 

+ An optional card authentication key; 

+ An optional digital signature key; and 

+ An optional key management key. 

Table 3-1 establishes specific requirements for cryptographic algorithms and key sizes for each 

key type. Table 3-1 also specifies two time periods with different sets of acceptable algorithms

for each key type. Note that digital signature and key management keys must transition to larger 

key sizes by 2008, while authentication keys must transition by 2010. This requirement 

anticipates that digital signature and key management keys will be used to protect data for longer 

periods of time, while data enciphered with authentication is generally not retained, and should 

not include private or secret information. 

In addition to the key sizes, keys must be generated using secure parameters. Rivest, Shamir, 

Adleman (RSA) keys must be generated using appropriate exponents, as specified in Table 3-2. 

Elliptic curve keys must correspond to one of the following recommended curves from 

[FIPS186-3]: 

+ Curve P-224; 

+ Curve K-233; 

+ Curve B-233; 

+ Curve P-256; 

+ Curve K-283; or 

+ Curve B-283. 

A PIV Card that supports elliptic curve cryptography must support private key computations for 

one or more of the listed curves. Applications that rely upon the PIV Card to authenticate users 

may select which curves to implement based on the community of users. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

Note that the NIST recommended curves of 163 and 192 bits in [FIPS186-3] are not supported 

by this specification. While these curves have equivalent strength with 1024 bit RSA, FIPS 201 

implementations supporting elliptic curve should implement algorithms that will still be secure 

after 2010.1

Table 3-1. Algorithm and Key Size Requirements for PIV Key Types

PIV Key Type Time Period for Use Algorithms and Key Sizes

Through 12/31/2010 RSA (1024, 2048, or 3072 bits) 

ECDSA (Recommended Curves, 224 – 283 bits) 

PIV Authentication key 

After 12/31/2010 RSA (2048 or 3072 bits) 

ECDSA (Recommended Curves, 224 – 283 bits) 

Through 12/31/2010 2TDEA 

3TDEA 

AES-128, AES-192, and AES-256 

RSA (1024, 2048, or 3072 bits) 

ECDSA (Recommended Curves, 224 – 283 bits) 

Card Authentication key 

After 12/31/2010 3TDEA 

AES-128, AES-192, and AES-256 

RSA (2048 or 3072 bits) 

ECDSA (Recommended Curves, 224 – 283 bits) 

Through 12/31/2008 RSA (1024, 2048, or 3072 bits) 

ECDSA (Recommended Curves, 244 – 283 bits) 

Digital Signature key 

After 12/31/2008 RSA (2048 or 3072 bits) 

ECDSA (Recommended Curves, 224 – 283 bits) 

Through 12/31/2008 RSA key transport (1024, 2048, or 3072 bits)

ECDH or ECC MQV (Recommended Curves, 224 – 

283 bits) 

Key Management key 

After 12/31/2008 RSA key transport (2048 or 3072 bits); 

ECDH or ECC MQV (Recommended Curves, 224 – 

283 bits) 

This specification also restricts the size of the RSA exponent. Implementations of this 

specification must choose an exponent greater than or equal to 65,357. Upper bounds for the 

exponent are based on key length; see Table 3-2 for complete details. 

Note that SP 800-73 specifies mechanisms that indicate the algorithm and key size for 

asymmetric private keys and symmetric secret keys stored on the PIV Card. For elliptic curve 

keys, these mechanisms also indicate which curve is associated with the private key. The 

mechanisms specified in SP 800-73 must be used to indicate the algorithm associated with 

private and secret keys stored on the PIV Card. 

 

1

 Note that 1024 bit RSA is permitted to leverage current products and promote efficient adoption of FIPS 201, but

must be phased out by 2010 for authentication keys and 2008 for digital signatures and key management. 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

Table 3-2. RSA Public Key Exponents

RSA Modulus Size Minimum exponent Maximum exponent

1024 65,537 (216 + 1) 2864 – 1 

2048 65,537 21824 – 1 

3072 65,537 22816 – 1 

This specification requires that the Key Management key must be an RSA key transport key, an 

Elliptic Curve Diffie-Hellman (ECDH) key, or an elliptic curve Menezes-Qu-Vanstone (MQV) 

key. The specification for RSA key transport is [PKCS1]; the specification for ECDH and 

elliptic curve MQV is the forthcoming [SP800-57]. 

3.2 Authentication Information Stored on the PIV Card 

3.2.1 Specification of Digital Signatures on Authentication Information 

FIPS 201 requires the use of digital signatures to protect the integrity and authenticity of 

information stored on the card. FIPS 201 and SP 800-73 require digital signatures on the 

following objects stored on the PIV Card: 

+ The CHUID; 

+ Biometric information (e.g., fingerprints); 

+ the SP 800-73 Security Object; and

+ X.509 public key certificates. 

Table 3-3 provides specific guidance for digitally signed information stored on the PIV Card. 

The first column specifies two time periods; the remaining columns specify public key 

algorithms and hash algorithms for generating digital signatures. For signatures on the CHUID, 

800-73 Security Object, and stored biometrics, the size of the public key and the hash algorithm

that must be used to generate the signature is determined by the expiration date of the PIV Card. 

For X.509 certificates stored on the card, the size of the public key and the hash algorithm used 

to generate the signature is determined by the expiration date associated with the certificate. 

Agencies are cautioned that generating digital signatures with SHA-224 and SHA-256 may 

initially limit interoperability. 

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Table 3-3. Signature Algorithm and Key Size Requirements for PIV Information 

Card or 

Certificate 

Expiration Date

Public Key Algorithms 

and Key Sizes 

Hash Algorithms Padding Scheme

RSA (1024, 2048, or 3072 bits) SHA-1 or SHA-256 PKCS #1 v1.5

Through RSA (1024, 2048, or 3072 bits) SHA-256 PSS 

12/31/2010 ECDSA (Recommended Curves, 

224 – 283 bits) 

SHA-1, SHA-224 or SHA-256 N/A 

RSA (2048 or 3072 bits) SHA-256 PKCS #1 v1.5, PSS 

After 12/31/2010 ECDSA (Recommended Curves, 

224 – 283 bits) 

SHA-1, SHA-224 or SHA-256 N/A 

FIPS 201, SP 800-73, and the forthcoming SP 800-76 specify formats for the CHUID, the 

Security Object, the biometric information, and X.509 public key certificates which rely on 

object identifiers (OID) to specify which signature algorithm was used to generate the digital 

signature. The object identifiers specified in Table 3-4, below, must be used in FIPS 201 

implementations to identify the signature algorithm. Note that RSA digital signatures may be 

generated using either the PKCS #1 v.1.5 padding scheme or the Probabilistic Signature Scheme

(PSS) padding. Most current implementations of RSA use the padding scheme defined in PKCS 

#1 v.1.5. The PSS padding scheme OID is independent of the hash algorithm; the hash 

algorithm is specified as a parameter (for details, see [PKCS1]). Implementations of this 

specification must use the SHA-256 hash algorithm when generating RSA-PSS signatures. 

Agencies may wish to transition to the PSS padding scheme as they transition to SHA-256. 

Table 3-4. FIPS 201 Signature Algorithm Object Identifiers 

Signature Algorithm Object Identifier 

RSA with SHA-1 and 

PKCS v1.5 padding 

sha1WithRSAEncryption ::= {iso(1) member-body(2) us(840) rsadsi(113549) 

pkcs(1) pkcs-1(1) 5} 

RSA with SHA-256 and 

PKCS v1.5 padding 

sha256WithRSAEncryption ::= {iso(1) member-body(2) us(840) rsadsi(113549) 

pkcs(1) pkcs-1(1) 11} 

RSA with SHA-256 and 

PSS padding 

id-RSASSA-PSS ::= {iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 

pkcs-1(1) 10} 

ECDSA with SHA-1 Ecdsa-with-SHA1 ::= {iso(1) member-body(2) us(840) ansi-X9-62(10045) 

signatures(4) 1}

ECDSA with SHA-224 ecdsa-with-SHA224 ::= {iso(1) member-body(2) us(840) ansi-X9-62(10045)

signatures(4) ecdsa-with-SHA2(3) 1} 

ECDSA with SHA-256 ecdsa-with-SH256 ::= {iso(1) member-body(2) us(840) ansi-X9-62(10045) 

signatures(4) ecdsa-with-SHA2 (3) 2} 

3.2.2 Specification of Public Keys In X.509 Certificates 

FIPS 201 requires generation and storage of an X.509 certificate to correspond with each 

asymmetric private key contained on the PIV Card. X.509 certificates include object identifiers 

to specify the cryptographic algorithm associated with a public key. Table 3-5, below, specifies 

the object identifiers that may be used in certificates to indicate the algorithm for a subject public 

key. Note that symmetric key algorithms are omitted from this table; in these cases there is no 

need for an X.509 certificate. 

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Table 3-5. Public Key Object Identifiers for PIV Key Types 

PIV Key Type 

Asymmetric

Algorithm Object Identifier 

PIV Authentication key; RSA {iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 1} 

Card Authentication 

key;

Digital Signature key 

ECDSA 

{iso(1) member-body(2) us(840) ansi-X9-62(10045) idpublicKeyType(2) 1} 

RSA {iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-1(1) 1} 

Key Management key ECDH or 

ECC MQV 

{iso(1) member-body(2) us(840) ansi-X9-62(10045) idpublicKeyType(2) 1} 

Note that a single object identifier is specified in Table 3-5 for all elliptic curve keys. An 

additional object identifier must be supplied in a parameters field to indicate the elliptic curve 

associated with the key.2

 Table 3-6 below identifies the named curves and associated OIDs. 

(RSA exponents are encoded with the modulus in the certificate’s subject public key, so the OID 

is not affected.) 

Table 3-6. ECC Parameter Object Identifiers for Approved Curves

Asymmetric

Algorithm Object Identifier 

Curve P-224 ansip224r1 ::= { iso(1) identified-organization(3) certicom(132) curve(0) 33 } 

Curve K-233 ansit233k1 ::= { iso(1) identified-organization(3) certicom(132) curve(0) 26 } 

Curve B-233 ansit233r1 ::= { iso(1) identified-organization(3) certicom(132) curve(0) 27 } 

Curve P-256 ansip256r1 ::= { iso(1) member-body(2) us(840) ansi-X9-62(10045) curves(3) prime(1) 7 }

Curve K-283 ansit283k1 ::= { iso(1) identified-organization(3) certicom(132) curve(0) 16 } 

Curve B-283 ansit283r1 ::= { iso(1) identified-organization(3) certicom(132) curve(0) 17 } 

3.2.3 Specification of Message Digests in the SP 800-73 Security Object 

SP 800-73 mandates inclusion of a Security Object consistent with the Authenticity/Integrity 

Code defined by the International Civil Aviation Organization (ICAO) in [MRTD]. This object 

contains message digests of other digital information stored on the card (e.g., the cryptographic 

keys and biometric information) and is digitally signed. Table 3-7 identifies the hash algorithms

that may be used to compute the message digests. The set of acceptable algorithms depends 

upon the expiration date of the PIV Card, since the hash algorithm must protect the data during 

the entire card lifetime. The Security Object format identifies the hash algorithm used when 

computing the message digests by inclusion of an object identifier; the appropriate object 

identifiers are identified in Table 3-8.

 

2

 Note that the parameters may be specified in the cardholder’s public key certificate, or inherited from the issuer’s 

certificate. Regardless of source, the OIDs specified in Table 3-5 apply. 

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Table 3-7. Hash Algorithm Requirements for the 800-73 Security Object 

Card Expiration Date Algorithm 

Through 12/31/2010 SHA-1, SHA-224 or SHA-256

After 12/31/2010 SHA-224 or SHA-256 

Table 3-8. Hash Algorithm Object Identifiers for the 800-73 Security Object 

Hash Algorithm Algorithm OID 

SHA-1 id-sha1 ::= {iso(1) identified-organization(3) oiw(14) secsig(3) algorithms(2) 26} 

SHA-224 id-sha224 ::= {joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) 

nistalgorithm(4) hashalgs(2) 4}

SHA-256 id-sha256 ::= {joint-iso-itu-t(2) country(16) us(840) organization(1) gov(101) csor(3) 

nistalgorithm(4) hashalgs(2) 1}

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4. Certificate Status Information 

The FIPS 201 functional component PIV Card Issuance and Management Subsystem generates 

and distributes status information for PIV asymmetric keys. FIPS 201 mandates two formats for 

certificate status information: 

+ X.509 CRLs; and

+ OCSP status response messages. 

The CRLs and OCSP status responses are digitally signed to support authentication and integrity. 

Table 4-1 below provides specific guidance for digital signatures on PIV status information. For 

signatures on the CRLs or OCSP status response messages, the size of the public key and the 

hash algorithm used to generate the signature may be determined by the date the CRL or OCSP 

message was generated. 

Table 4-1. Signature Algorithm and Key Size Requirements for PIV Status Information 

CRL or OCSP 

Response 

Generation Date

Public Key Algorithms 

and Key Sizes 

Hash Algorithms Padding Scheme

RSA (1024, 2048, or 3072 bits) SHA-1 or SHA-256 PKCS #1 v.1.5

RSA (1024, 2048, or 3072 bits) SHA-256 PSS 

Through 12/31/2010 

ECDSA (Recommended Curves, 

224 – 283 bits) 

SHA-224 or SHA-256 N/A 

After 12/31/2010 RSA (2048 or 3072 bits) SHA-256 PKCS #1 v.1.5, PSS 

ECDSA (Recommended Curves, 

224 – 283 bits) 

SHA-224 or SHA-256 N/A 

CRLs and OCSP messages rely on object identifiers to specify which signature algorithm was 

used to generate the digital signature. The algorithms and key sizes specified in Table 3-3 must 

be used to sign CRLs and OCSP responses. The object identifiers specified in Table 3-4 must be 

used in CRLs and OCSP messages to identify the signature algorithm. 

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5. PIV Card Management Keys

PIV Cards may support card activation by the card management system to support card 

personalization and post-issuance card update. PIV Cards that support card personalization and 

post-issuance perform a challenge response protocol using a symmetric cryptographic key (i.e., 

the PIV Card Management Key) to authenticate the card management system. After successful 

authentication, the card management system can modify information stored the PIV Card. Table 

5-1 below, establishes specific requirements for cryptographic algorithms and key sizes for PIV 

Card Management keys according to the card expiration date. 

Table 5-1. Algorithm and Key Size Requirements for Card Management Keys 

Card Expiration Date Algorithm 

Through 12/31/2010 2TDEA 

3TDEA 

AES-128, AES-192, and AES-256 

After 12/31/2010 3TDEA 

AES-128, AES-192, and AES-256 

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Appendix A—Acronyms 

The following abbreviations and acronyms are used in this standard: 

2TDEA Two key TDEA 

3TDEA Three key TDEA 

AES Advanced Encryption Standard specified in [FIPS197]. 

CA Certificate Authority

CBEFF Common Biometric Exchange Formats Framework 

CHUID Cardholder Unique Identifier

CRL Certificate revocation list

ECDSA Elliptic Curve Digital Signature Algorithm

ECDH Elliptic Curve Diffie-Hellman Algorithm

ECC MQV ECC Menezes-Qu-Vanstone Algorithm

FIPS Federal Information Processing Standard 

FISMA Federal Information Security Management Act 

HSPD Homeland Security Presidential Directive 

ICAO International Civil Aviation Organization 

ITL Information Technology Laboratory

MQV Menezes-Qu-Vanstone cryptographic algorithm

NIST National Institute of Standards and Technology

OCSP Online Certificate Status Protocol 

OID Object Identifier

OMB Office of Management and Budget 

PIV Personal Identity Verification

PKI Public Key Infrastructure 

PSS Probabilistic Signature Scheme

RSA Rivest, Shamir, Adleman cryptographic algorithm 

SHA Secure Hash Algorithm

SP Special Publication

TDEA Triple Data Encryption Algorithm; Triple DEA 

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Special Publication 800-78 Cryptographic Algorithms and Key Sizes for PIV 

Appendix B—References 

[FIPS186-3] Federal Information Processing Standard 186-3, Digital Signature Standard 

(DSS), (Revision of FIPS 186-2, June 2000), to be published. 

[FIPS197] Federal Information Processing Standard 197, Advanced Encryption Standard 

(AES), November 2001. 

[FIPS201] Federal Information Processing Standard 201, Personal Identity Verification 

(PIV) of Federal Employees and Contractors, February 2005. 

[MRTD] PKI for Machine Readable Travel Documents Offering ICC Read-Only Access 

Version - 1.1 Date - October 01, 2004. Published by authority of the Secretary 

General, International Civil Aviation Organization. 

[PKCS1] Jonsson, J., and B. Kaliski, "PKCS #1: RSA Cryptography Specifications Version 

2.1", RFC 3447, February 2003. 

[RFC 3279] Polk, W., Housley, R., and L. Bassham, "Algorithms and Identifiers for the 

Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation 

Lists (CRL) Profile", RFC 3279, April 2002. 

[SP800-56] Draft NIST Special Publication 800-56, Recommendation on Key Establishment 

Schemes. (See http://csrc.nist.gov) 

[SP800-57] Draft NIST Special Publication 800-57, Recommendation on Key Management. 

(See http://csrc.nist.gov) 

[SP800-67] NIST Special Publication 800-67, Recommendation for Triple Data Encryption 

Algorithm Block Cipher, May 2004. 

 [SP800-73] NIST Special Publication 800-73, Interfaces for Personal Identity Verification, 

April 2005. 

[SP800-76] Draft NIST Special Publication 800-76, Biometric Data Specification for 

Personal Identity Verification, February, 2005. 

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