The following definitioins are from "Licensing of Trusted Third Parties for
the Provision of Encryption Services -- Public Consultation paper on
Detailed Proposals for Legislation," March 1997, Department of Trade and
Industry, United Kingdom.

Annex D:

Glossary of Terms 

The following terms are described for information only and are not intended
to be interpreted as legal definitions: 

                                                                                
                                                                                

Authentication:            The verification of a claimed identity.              
                                                                                

Central Repository:        Government department or agency set up by            
                           Government to act as a point of contact for          
                           interfacing between a TTP and the appropriate law    
                           enforcement agency.                                  
                                                                                

Confidentiality:           The prevention of the unauthorised disclosure of     
                           information.                                         
                                                                                

Cryptographic key:         Is a parameter used with a cryptographic algorithm   
                           to transform, validate, authenticate, encrypt or     
                           decrypt data.                                        
                                                                                

Cryptography:              The art or science of keeping messages secure.       
                                                                                

Digital Signature:         Data appended to a message that allows a recipient   
                           of the message to prove the source and integrity
  
                           of the message.

                                                                                

Dual Legality:             A legal request from a foreign agency must satisfy   
                           legal access conditions in both the requesting       
                           country and the country being asked.                 
                                                                                

Encryption Algorithm:      A mathematical function used to change plaintext     
                           into ciphertext (encryption) or vice versa           
                           (decryption).                                        
                                                                                

Integrity:                 Prevention of the unauthorised modification of       
                           information.                                         
                                                                                

Key escrow / recovery      A capability that allows authorised persons, under   
                           certain prescribed conditions, to decrypt            
                           ciphertext with the help of information supplied 
 
                           by one or more trusted parties.


                                                                                

Key management:            The process of generating, storing, distributing,    
                           changing, and destroying cryptographic keys.         
                                                                                

Key revocation:            Notification that a public cryptographic key is no   
                           longer valid.                                        
                                                                                

Private key:               The private (secret) part of a cryptographic key     
                           pair. Knowledge of which should be strictly          
                           limited.                                             
                                                                                

Public key certificate:    Public key information of an entity, signed by a     
                           trusted entity to certify the integrity of the       
                           public key.                                          
                                                                                

Public Key Infrastructure  Supporting infrastructure, including non-technical   
(PKI):                     aspects, for the management of public keys.          
                                                                                

Public key:                The public (i.e. non secret) part of a               
                           cryptographic key pair. This key is widely known     
                           and no secrecy should be attached to it.             
                                                                                

Time stamping:             An electronic equivalent of mail franking.           
                                                                                

Trusted Third Party        An entity trusted by other entities with respect 

(TTP):                     to security related services and activities.