@startuml Message Retransmission
header Message Retransmission / Service Library
  
component "Publisher"{
    [OBS_Pub] 
    [MRS_Pub1] 
}

component "Consumer"{
    [MRS_Con1] 
    [OBS_Sub]
}
 
component "Content Delivery Management Server(Pub)" as CDMS_Pub{
    "DataController" as [DataController1]
    [MRS_Pub2]
}

component "Content Delivery Management Server(Con)" as CDMS_Con{
    "DataController" as [DataController2]
    [MRS_Sub2]
}

database "Database" as Database_Pub {
    folder "This is log Location 1" {
        [Messages]
    }
}
database "Database" as Database_Con {
    folder "This is log Location 2" {
        [Messages2]
    }
}
[MRS_Pub1] -- [MRS_Con1]  : Basic Synchronization

[MRS_Pub1] - [OBS_Pub]
[MRS_Con1]  - [OBS_Sub]
  
[OBS_Pub] .> CDMS_Pub
[MRS_Pub2] - [DataController1] 
[DataController1] .> Database_Pub:Write Data  
[OBS_Sub] .> CDMS_Con 
[MRS_Sub2] - [DataController2]  
[DataController2] <. Database_Con:Read Data

[MRS_Pub2] -- [MRS_Sub2]
' CDMS_Pub - CDMS_Con : Synchronization over MRS library 

@enduml

' Square are ports. I use them to represent the Message Retransmission Service
' So, when Publisher creates messages from the relevant library, it will then
' store in to it's own designated database, and will also attempt to broadcast
' to the consumer it's relevant information. 
' They can perform basic synhronization or utilzie the CDMC: Content Delivery Management Server
' to manage the message payload by leveraging the MRS library to do the synching
' MRS library will check the data loss by taking the specified data to be 
' compared and then perform retransmission if needed.

' Rearrage the position
' use MR_S_Pub1 MR_S_Con1 MR_S_Pub2 MR_S_Con2