Study carefully the following key distribution scenario and answer the questions below:

The purpose of this scenario is:

The technique $($enforcer$)$ used to distribute the key in the above scenario is

The parameter that is usually used to ensure the freshness of the transmitted data and protect it from replay attacke

Public key of B $($Pub$)$

Private key of $A($ PRa $)$

Nonce value $($N$2)$

ID of A $($IDA$)$