The Evolving Federal PKIThe Evolving Federal PKI

Richard Guida, P.E.

Chair, Federal PKI Steering Committee

Richard.Guida@cio.treas.gov; 202-622-1552

(Steering Committee web page: http://gits-sec.treas.gov)

E-Transaction LandscapeE-Transaction Landscape

• Intra-agency– personnel matters, agency management

• Interagency– payments, account reconciliation, litigation

• Agency to trading partner– procurement, regulation

• Agency to the public

E-Transactions DriversE-Transactions Drivers

• Long-term cost savings

• Trading partner practices (e.g., banks)

• Public expectations

• Federal/State Statutes (e.g., GPEA) and policies

• International competition

Challenges All Applications FaceChallenges All Applications Face

• Authentication of Users

• Non-repudiation for transactions

• Confidentiality (privacy)

• Interoperability

• Liability

• Scalability/extensibility

Public Key TechnologyPublic Key Technology

• Authentication

• Technical non-repudiation

• Data integrity

• Confidentiality

• Interoperability

• Scalability/extensibility

6

How PK Technology WorksHow PK Technology Works

• Two keys, mathematically linked

• One is kept private, other is made public

• Private not deducible from public

• For digital signature: One key signs, the other validates

• For confidentiality: One key encrypts, the other decrypts

Digital Signature (exampleDigital Signature (example)

• Sender hashes document, signs hash with private key and sends with document

• Recipient hashes document he or she received, creating “raw hash”

• Recipient applies public key of sender to signed hash to get sender’s raw hash

• If raw hashes are same, transaction validates

Confidentiality (example)Confidentiality (example)

• Sender generates symmetric encryption key and encrypts document with it

• Sender encrypts symmetric key with public key of recipient, sends that and encrypted document to recipient

• Recipient decrypts symmetric key with his or her private key

• Recipient decrypts document with symmetric key

The Critical QuestionsThe Critical Questions

• How can the recipient know with certainty the sender’s public key? (to validate a digital signature)

• How can the sender know with certainty the recipient’s public key? (to send an encrypted message)

A document which -

• is digitally signed by a trusted third party (called Certification Authority)

• is based on identity-proofing done by a Registration Authority

• contains the individual’s public key and some form of the individual’s identity

• has a finite validity period

Public Key CertificatePublic Key Certificate

11

X.509 v3 CertificateX.509 v3 Certificate

Public Key InfrastructurePublic Key Infrastructure

• Registration Authorities to identity proof users

• Certification Authorities to issue certificates and CRLs

• Repositories (publicly available data bases) to hold certificates and CRLs

• Some mechanism to recover data when encryption keys are lost/compromised

• Certificate Policy and related paper

Federal PKI ApproachFederal PKI Approach

• Establish Federal PKI Policy Authority (for policy interoperability)

• Implement Federal Bridge CA using COTS (for technical interoperability)

• Deal with directory issues in parallel– Border directory concept

– Use ACES for public transactions

Federal PKI Policy Authority Federal PKI Policy Authority

• Voluntary interagency group - NOT an “agency”

• Governing body for interoperability through FBCA– Agency/FBCA certificate policy mappings

• Oversees operation of FBCA, authorizes issuance of FBCA certificates

• Six charter members

Federal Bridge CAFederal Bridge CA

• Non-hierarchical hub (“peer to peer”)

• Maps levels of assurance in disparate certificate policies (“policyMapping”)

• Ultimate bridge to CAs external to Federal government

• Directory initially contains only FBCA-issued certificates and ARLs

Current StatusCurrent Status

• Prototype FBCA: Entrust, Cybertrust (replaced with Baltimore Unicert)– Initial operation 2/8/00

• Production FBCA: add other CAs– Operational by late 00

• FBCA Operational Authority is GSA (Mitretek technical lead and host site)

• FBCA Cert Policy by mid-00

• FPKIPA operational 7/00

Cybertrust CA Entrust CA

SFL

Client Entrust

Client Entrust

Client SFL

Client

DoD Bridge CA

Entrust

Client Entrust

Client Entrust

Client

PCA

PCA

CA

PCA

CA

CA CA

PCA

CACA

PCA

CA

CAPCAPCAPCA

Entrust

Client SFL

Client

PCA

Intra-Agency PKI ExamplesIntra-Agency PKI Examples

• DOD (>300K certs => >>4M by 2002; high assurance with smartcards)

• FAA (~1K certs => 20K+ in 2000; software now, migrating to smartcards)

• FDIC (~7K certs => 20K+ in 2000)

• NASA (~1K certs => 25K+ in 2000)

• USPTO (>1K certs => 15K+ in 2000)

Planned Interagency UsesPlanned Interagency Uses

• VA and SSA on medical evidence

• Dept of Education, SSA, VA on student loan applications, disbursements

• USDA/NFC for on-line payroll matters

• DOD/Treasury re: payments

• FDIC/other financial regulators re: sharing information

Border Directory ConceptBorder Directory Concept

InternalDirectory

Infrastructure

PCA 2

FBCADSA

InternalDirectory

Infrastructure BorderDSA 2

X.500 DSA

BorderDSA 1

LDAP Server

InternalDirectory

Infrastructure

PCA 1 PCA 3

Agency 1 Agency 2

Agency 3

FBCA

LD

AP

Que

ry-R

espo

nse

X.500 - D

SP

chaining

Access Certs for Electronic ServicesAccess Certs for Electronic Services

• “No-cost” certificates for the public

• For business with Federal agencies only (but agencies may allow other uses on case basis)

• On-line registration, vetting with legacy data; information protected under Privacy Act

• Regular mail one-time PIN to get certificate

• Agencies billed per-use and/or per-certificate

Access Certs for Electronic ServicesAccess Certs for Electronic Services

• RFP 1/99; bids received 4/99; first award 9/99 (DST), second award 10/99 (ORC), third award 10/99 (AT&T)

• Provisions for ACES-enabling applications, and developing customized PKIs

• Agencies do interagency agreement with GSA

• Certificates available now (President used the first one in signing E-Sign bill 6/30/00)

USPS IssuesUSPS Issues

• USPS very well positioned to serve as RA

• USPS partnering with AT&T and IBM on branded secure e-mail

• USPS intends to interoperate with FBCA and thus support multiple CA sources

• Bottom line: USPS can become important source of PKI products and services to Federal agencies

Commercial ImplementationsCommercial Implementations

• Scotiabank (300K+ certs; 500K transactions per month)

• American Express “Blue”

• Identrus bank consortium

• Large manufacturing companies for internal uses (GE, automobile manufacturers)

Electronic Signatures under GPEAElectronic Signatures under GPEA

• Government Paperwork Elimination Act (October 1998)

• Technology neutral - agencies select based on specifics of applications (e.g., risk)– But full recognition of dig sig strengths

• Gives electronic signature full legal effect

• Focus: transactions with Federal agencies

• Draft OMB Guidance 3/99; final 5/00

OrganizationOrganization

S ecu rity, P rivacy, C rit ica l In fras tru c tu re C om m ittee

B u s in ess W G Tech n ica l W G L eg a l/P o licy W G

F ed era l P u b lic K ey In fras tru c tu re S teerin g C om m ittee

E n terp rise In te rop erab ility C om m ittee

F ed era l C h ie f In fo rm ation O ffice r C ou n c il

Federal PKI Steering CommitteeFederal PKI Steering Committee

• Over 50 members from two dozen agencies• Three Working Groups

– Business– Technical– Legal and Policy

• Minutes/activities on the web• http://gits-sec.treas.gov

PKI Use and Implementation IssuesPKI Use and Implementation Issues

• Misunderstanding what it can and can’t do

• Requiring legacy fixes to implement

• Waiting for standards to stabilize

• High cost - a yellow herring

• Interoperability woes - a red herring

• Legal trepidation - the brightest red herring

Legal trepidation - the brightest red herringLegal trepidation - the brightest red herring

• PK technology is NOT the most complex subject presented in a courtroom

• Case law only develops when you use something

• Technology and commerce marches on regardless of legal uncertainties

• Unreasonable to demand standard of proof higher than in paper world