I have a desktop application and web application. The desktop application data is updated offline and when online it needs to be uploaded to the web application. Current it uses web services to upload the data. The web service will handle one record at a time. This procedure is taking a long time for all the data to upload. What can I do to improve the performance and still the desktop application know which records needs uploading.

 Thanks

Why do you pass one record each time? can't you pass an array or something?

You can you use remoting also. 

I believe your desktop application has it's own local database. Firstly to keep track of which records needs to be updated to Web DB, add a column IsSync of type bit (boolean) default (0).
Secondly re-write your Web Service to accept multiple rows at a time. And in the desktop app, loop through the rows where IsSync=0 and send those updates. After they are updated, set it to 1 so that it is not sent for update again.

In case the row is edited by the desktop app again, set the IsSync to 0 so that it is sent for update again.

Thank you all,

Now I use an array to upload multiple data.