The Token Key Service (TKS) is an optional PKI subsystem that manages the
master key(s) and the transport key(s) required to generate and distribute
keys for hardware tokens. TKS provides the security between tokens and an
instance of Token Processing System (TPS), where the security relies upon the
relationship between the master key and the token keys. A TPS communicates
with a TKS over SSL using client authentication.
TKS helps establish a secure channel (signed and encrypted) between the token
and the TPS, provides proof of presence of the security token during
enrollment, and supports key changeover when the master key changes on the
TKS. Tokens with older keys will get new token keys.
Because of the sensitivity of the data that TKS manages, TKS should be set up
behind the firewall with restricted access.
