@startuml

hide footbox
participant Capteur as capt
database Cloud as cld

cld -> capt ++: CON[0x45]\nGET/URL
{start} capt --> cld : ACK[0x45]
{end} capt -> cld : CON[0xdc]\nval
{start} <-> {end} : determination de val
cld --> capt !!: ACK[0xdc]

@enduml