- The roadwarriors <b>carol</b> and <b>dave</b> set up a connection to gateway <b>moon</b>.
 
- At the outset the gateway authenticates itself to the clients by sending
 
- an IKEv2 <b>RSA signature</b> accompanied by a certificate.
 
- The roadwarrios then use the <i>Extensible Authentication Protocol</i>
 
- in association with an  <i>MD5</i> challenge and response protocol
 
- (<b>EAP-MD5</b>) to authenticate against the gateway <b>moon</b> and includes
 
- a <b>Postquantum Preshared Key (PPK)</b> that's also mixed into the
 
- derived key material. The PPK_ID used by <b>dave</b> is unknown to <b>moon</b>
 
- but since both peers don't enforce the use of a PPK they fall back to regular
 
- authentication by use of the authentication data provided in the NO_PPK_AUTH
 
- notify.
 
 
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