Common NetMsg Exchanges

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Revision as of 09:09, 4 December 2008 by Dloman (talk | contribs)
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Inter-Application Connect

This sequence of NetMsg exchanges represents the communications between an external application (App M) attempting to connect to a running Geometry Service (App GS). This sequence assumes success.

Main Sequence

  1. App GS waits for incoming socket requests.
  2. App M creates a socket connection to App GS.
  3. App GS accepts the socket connection.
  4. App M and App GS are now connected at the socket level.
  5. App M sends a RemHostNameSET NetMsg to App GS.
  6. App GS checks its RemHostName list for duplicates. (Alt #1)
  7. App GS sends a RemHostNameSETOK NetMsg to App M.
  8. App GS sends a RemHostNameSET NetMsg to App M.
  9. App GS waits for App M to send a RemHostNameSETOK NetMsg.
  10. App M sends a RemHostNameSETOK NetMsg.
  11. App M is now connected to the Geometry Service network.
  12. App M sends a NewSessionREQ NetMsg.
  13. App GS creates a new Session.
  14. App GS sends a NewSessionREQOK NetMsg.

Alt Sequence #1

6a. App GS finds that the incoming Host is already on the HostList. Either a duplicate name, or a duplicate connection.
6b. App GS sends App M a RemHostNameSETFAIL NetMsg.
6c. App GS drops socket connection to App M.
6d. App M drops socket connection to App GS.


Request For Geometry

This sequence of NetMsg exchanges represents the communications between an external application (App M) as it requests Geometry from the Geometry Service (App GS). This sequence assumes success and that both App M and App GS have completed the Inter-Application Connect.

Main Sequence

  1. App M sends a GeometryREQ NetMsg to App GS.
  2. App GS finds the request Geometry. (Alt #1)
  3. App GS sends App M a GeometryMANIFEST NetMsg.
  4. App GS sends App M as many GeometryCHUNK NetMsgs as required in order to fulfill the GeometryMANIFEST.

Alt Sequence #1

2a. App GS does NOT find requested Geometry.
2b. App GS sends App M a GeometryREQFAIL NetMsg.


Inter-Application Disconnect

This sequence of NetMsg exchanges represents the communications between an external application (App M) and a Geometry Service (App GS) during a disconnect event. The disconnect event can be generated by either side as the effect will be the same. This sequence assumes success and that App M initiates the disconnect event.

Main Sequence

  1. App M prepares all data for an impending disconnect event.
  2. App M sends a DisconnectREQ NetMsgs to App GS.
  3. App GS receives the DisconnectREQ
  4. App GS prepares all of its data for an impending disconnect event.
  5. App GS commands the ConnectionManager to close the appropriate socket.
  6. App M detects the closed socket.
  7. App M and App GS are disconnected.