If it's over the internet, the speeds would typically be lesser than what you get on the intranet or LAN. If you want to improve the speeds for fetching/updating data, you would have to look at the UI design and navigation, and check the data access code. For e.g. after the user logs in and goes to the order management screen, it would not be a good idea to show him all the orders at the start. Instead you can ask the user to specify some search criteria and make him click a button, which then fetches the necessary records. Also while updating, you should only pass data that needs to be updated, instead of passing everything, changed or not.

Please note this is general advice. Any particular steps you take will have to be checked with the specifics of the situation you are in.

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