Architectural Overview of a RoundTrip Internet session

The major components of the Internet Server RTRT Monitor are Session, Send and Timer component (SST): This component contains session information for all the RoundTrip sessions that are currently active; three sets of timers for the send interval, alarm interval, and the warn interval; and a module to send email messages to the target server.

 RoundTrip Internet session architecture 

 

The interaction between the various components is shown in the following figure for an active RoundTrip Internet session between the source Exchange server and the foreign mail server:

1. The Send Interval timer for the active session expires, and a component (1) on the source Exchange server sends an email message to an invalid user on the foreign mail server.
2. If the email is addressed to invalidUser@domain, the DNS Server is queried for multiplexer records pointing to the foreign mail server, and the email is forwarded to the foreign mail server. If the mail is addressed to invalidUser@fullyQualifiedDomainNameOfMailServer, the email is sent directly to the foreign mail server.
3. The foreign mail server receives the email and forwards it to the postmaster or administrator of the foreign mail server because the email is addressed to an invalid user.
4. The foreign mail server automatically sends a Non-Delivery Report to the source Exchange server.
5. A component (2) on the source Exchange server is notified of the arrival of the reply email message from the foreign mail server. After it parses the reply message, it calculates the RoundTrip response time. If a reply message does not arrive at the source Exchange server within the Warn or Alarm interval, the corresponding Warn or Alarm timers in component (1) times out.

6. A component (3) on the source Exchange server notifies the PATROL Agent with the calculated RoundTrip times, if they were obtained, or sends an Alarm or Warn notification if the response from the foreign mail server was not obtained within the Alarm or Warn intervals.

   Note

   All of the components listed are contained in the following files and processes:

   • MSEXCHInetE2E.exe
   • MSEXCHInetE2E_Proxy.exe
   • MSEXCHInetE2E_EvSink.dll
   • MSEXCHInetE2E_SendMail.exe
   • MSEXCHInetE2E_Security.exe