Addition of figure 9.3

@startuml

skinparam monochrome true

skinparam defaultFontName Arial

skinparam classFontSize 10

skinparam sequenceBoxBorderColor #black

participant "**Accessor Authentication Service**" as aas 

participant "**Accessor Authentication Application**" as aaa 

autonumber

...

aas->aaa: aChallenge 

note right

[eSK.AAA.ECKA,ePK.AAA.ECKA]=ECDHE()

Certification_Path<sub>ATK_AAA</sub>=GENTOKEN(Certification_Path<sub>AAA</sub>,eSK.AAA.ECKA,ePK.AAA.ECKA)

end note

...  

aaa->aas: Certification_Path<sub>ATK_AAA</sub> 

activate aas

note left of aas

VERIFY_PATH(PK.CI<sub>AAA</sub>.ECDSA)[Certification_Path<sub>AAA</sub>]

[eSK.AAS.ECKA,ePK.AAS.ECKA]=ECDHE()

Certification_Path<sub>ATK_AAS</sub>=GENTOKEN(Certification_Path<sub>AAS</sub>,eSK.AAS.ECKA,ePK.AAS.ECKA)

<b>ShS</b>=ECKA-DH(eSK.AAS.ECKA,ePK.AAA.ECKA)

end note

activate aaa

aas-->aaa: Certification_Path<sub>ATK_AAS</sub>  

deactivate aaa

deactivate aas

aaa->aaa

activate aaa

note right of aaa

VERIFY_PATH(PK.CI<sub>AAS</sub>.ECDSA)[Certification_Path<sub>ATK_AAS</sub>]

<b>ShS</b>=ECKA-DH(eSK.AAA.ECKA,ePK.AAS.ECKA) 

end note

deactivate aaa

@enduml