The Hierarchical Trust Model

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The Hierarchical Trust Model
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PGP Certificate Server details

• Fast, efficient key repository
• LDAP, HTTP interfaces
• Secure remote administration
• Pending area for unverified keys
• Server database replication
• PGPtls connection between client and server
• Database replication provides corporate branch
  offices with fast access to public keys
• via Replication Engine
• Solaris, Windows NT

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PGP Certificate Server

• Allows large-scale deployment of public keys for
  use in intranets and the Internet
• Allows centralized storage management of
  digital certificates
• Efficient LDAP/HTTP certificate distribution and
  searches
• Support for client synchronization of keys
• Scalable from small groups to multi-national
  corporations
• Customizable policy management rules
• Host of features remote access, administration,
  logging, replication engine to synchronize
  multiple servers
• Seamless integration with PGP client programs
• Windows NT 4.0 or Solaris 2.51 or above

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PGP Certificate Server for NT
Control
Monitor
Event Log
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Certifying Authority
Certifying Authority
Public Key
Encrypted Text
Decrypt
Encrypt
Private Key
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Process for Validating Keys

• User generates key, sends to server automatically
• Key is held in pending area, not added to main
  server database
• Administrator periodically checks pending area
  and manually verifies keys contained within to
  ensure authenticity
• Admin reconstitutes shared signing key and
  validates keys
• Keys are then added to server and made available

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Key splitting and PGPtls

• High-risk keys can be split and shared
• N of M shares required to reconstitute key for
  use
• ADKs, Corporate Signing Keys are good candidates
  for splitting
• Share holders dont have to be present!
• Secure connections between clients with PGPtls
  allow shareholders to be anywhere in the world
  and still reconstitute a split key

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PGP Certificate Server for central certificate
storage LDAP-based, both x509 and PGP spt
Scaleable certserver.nai.com vends over 500,000
certificates alone Extensible searching mechanism

• PGP Certificate Server for central certificate
  storage
• Provides scalability to PGP applications
• Supports hundreds of thousands of certificates
• certserver.nai.com vends over 500,000
  certificates
• LDAP-based

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PGP Certificate Server

• Large-Scale Deployment of Public Keys
• Efficient LDAP HTTP Certificate Distribution
• Scalable to Very Large Enterprises
• Customizable Policy Management Rules
• PKI Features Remote Access, Administration,
  Logging, Replication Engine, Multiple Trust
  Models, Validity Checking, Data Recovery
• Seamless Integration with PGP Clients

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PGP Certificate Server Operations
1. Alice creates message for Bob
2. Alice searches for Bobs public key on her
local key ring
3. Bobs key not found, auto-import key from
CertServer
4. CertServer returns Bobs valid key
5. Alices Client stores Bobs key locally
6. Alice encrypts to Bobs key sends...
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3
1,2,5
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Alice
Bob
CertServer
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PGP Enterprise Security Products

• Need Scalable and manageable PKI
• Solution PGP Certificate Server
• Scalable and replicated storage of public keys
• Integrated policy management
• Seamless integration with client