Allied Telesis AT-S63 User Manual

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AT-S63 Management Software Features Guide
Section IX: Management Security
409
Elements of a
Public Key
Infrastructure
A public key infrastructure is a set of applications which manage the 
creation, retrieval, validation and storage of certificates. A PKI consists of 
the following key elements:
ˆ
At least one certification authority (CA), which issues and revokes 
certificates. 
ˆ
At least one publicly accessible repository, which stores certificates 
and Certificate Revocation Lists.
ˆ
At least one end entity (EE), which retrieves certificates from the 
repository, validates them and uses them. 
End Entities (EE)
End entities own public keys and may use them for encryption and digital 
signing. An entity which uses its private key to digitally sign certificates is 
not considered to be an end entity, but is a certification authority.
The switch acts as an end entity.
Certification Authorities
A certification authority is an entity which issues, updates, revokes and 
otherwise manages public keys and their certificates. A CA receives 
requests for certification, validates the requester’s identity according to the 
CA’s requirements, and issues the certificate, signed with one of the CA’s 
keys. CAs may also perform the functions of end entities, in that they may 
make use of other CAs’ certificates for message encryption and 
verification of digital signatures.
An organization may own a certification authority and issue certificates for 
use within its own networks. In addition, an organization’s certificates may 
be accepted by another network, after an exchange of certificates has 
validated a certificate for use by both parties. As an alternative, an outside 
CA may be used. The switch can interact with the CA, whether a CA is part 
of the organization or not, by sending the CA requests for certification.
The usefulness of certificates depends on how much you trust the source 
of the certificate. You must be able to trust the issuing CA to verify 
identities reliably. The level of verification required in a given situation 
depends on the organization’s security needs.