The Eternity Service

1
The Eternity Service

• Threat model
• Service characteristic
• Design highlights
• Overall Service structure
• Protocols used
• Servers
• Implementation

http//www.mail.kolej.mff.cuni.cz/eternity/index.
html
2
Threat model

• Blunt influences - natural disasters, vandals,
  thieves
• Amateur opponent - moderate to good knowledge,
  restricted resources
• Professional opponent - excellent knowledge, high
  motivation, skilled stuff, sufficient resources
• Authorities - law enforcement, global influence

3
Service characteristics

• Services store data for agreed period, retrieve
  specified information
• World-wide system
• High reliability and availability
• Anonymity
• Fully distributed design
• No autentization, no privacy

4
Design goals

• Unlimited availability
• High resistance
• Extendibility
• Fully distributed design
• Portability and reusability

• In service upgrade
• Terseness and simplicity
• Separation of cryptography
• Good habits

5
Design guidelines

• Flat structure
• High ES protection
• Auxiliary servers
• Passive behaviour

• Randomness, concealing
• Two-layered implementation
• Freedom principle

6
Overall Service structure
7
Server types - Eternity Server

• Each ES represents an entry point
• Provides data storage capacity
• Assures information retrieval
• Automatically discards expired data
• Time synchronization
• Communication with banks

8
Server types - Mix server

• Padding traffic generation
• Supports erm message transfer
• Represents simple and cheap way to grow the
  system size

9
Server types - AC server

• Assures first contact with Service
• Collects certificates of servers
• Provides ES access certificates and Mix
  certificates to all subjects

10
Server types - EPX server

• Simple easy to use interface for amateur users
  without the need of a top quality protection
• Additional functions - secret splitting, privacy
  enhancement,
• Local cache for quicker access to frequently
  requested data

11
Access certificate
12
Eternity Routing Mechanism
13
ES internal structure
14
ES data storage
15
Implementation

• Platform
• Posix
• FreeBSD Unix
• RSAref Blowfish
• gcc

• Current state
• ES with sw-based TCB
• MX, ACS
• Client module
• (alpha versions)