@startuml

skinparam monochrome true
skinparam defaultFontName Arial
skinparam classFontSize 10
skinparam sequenceBoxBorderColor #black
participant "**SSP Host**\nAccessor Authentication Service Gate" as hosta_fs_ctr 
participant "**SSP Host**\nAdministration Gate" as hosta_adm
participant "**Other Host**\nAdministration Gate" as hostb_adm
participant "**Other Host**\nAccessor Authentication Application Gate" as hostb_fs_ctr 

autonumber

...**Notation:**  Gate Identifier : Pipe Session Open on [P<sub>IN</sub>,P<sub>OUT</sub>]...
note right : Pipe Session Open  on [P<sub>20</sub>,P<sub>10</sub>]
note left : Pipe Session Open on [P<sub>10</sub>,P<sub>20</sub>]
...
hostb_fs_ctr->hosta_fs_ctr: AAS-OP-AUTHENTICATE-ACCESSOR-Service-Command [Parameters...] on P<sub>10</sub>
activate hosta_fs_ctr
activate hostb_fs_ctr
hosta_fs_ctr-->hostb_fs_ctr: eAAS-OK on P<sub>20</sub> 
deactivate hostb_fs_ctr
deactivate hosta_fs_ctr
alt Successful authentication
hostb_fs_ctr->hosta_fs_ctr: AAS-ADMIN-UPDATE-ACCESSOR-Service-Command [Parameters...] on P<sub>10</sub>
activate hosta_fs_ctr
activate hostb_fs_ctr
hosta_fs_ctr-->hostb_fs_ctr: eAAS-OK on P<sub>20</sub> 
deactivate hostb_fs_ctr
deactivate hosta_fs_ctr
...
end
  
@enduml