title: Synchronizing SQL Data with or without a VPN
body: <p>I have written a Windows application that stores data locally in a SQL Server Express database.  It is used by multiple people from remote locations who need to synchronize their data occassionally.  It requires a fairly simple synchronization process of only a handful of tables and I'm currently accomplishing this by linking each of the SQL Express installations to the "central" SQL Server using a linked server.  I then run queries against the remote data and add/update/delete as needed.  This works really well.</p>
  
  <p>However, I'm having a difficult time with the VPN connection that is required to make this happen.  Before beginning the synchronization process, the first thing the user does is establish a VPN connection with the server (running RRAS on Windows 2003).  It works well most of the time, but I run into lots of irritating problems such as the VPN dropping if the connection isn't stable, often the AT&amp;T cellular connection fails to establish a VPN connection (remote users sometimes HAVE to use this method), and one user has two machines at home and only one can have a VPN connection at a given time due to a router limitation.  Some run XP, other Vista...it's really a pain and the VPN piece is proving to be very frustrating for me and the users.</p>
  
  <p>Do I have any fairly simple options that I'm overlooking?  My first thought is to use a webservice, but that would require passing all of my data to the server, through the webservice, for processing.  That's not practical.  Another thought is to install a second instance of SQL Server Express on the server, have it listen on a different port, and then connect directly this rather than through the VPN (I'm not even sure this will work with SQL Express.  Will it?).  I know this has security implications, but how much so?  The data is not confidential in nature, nor mission critical.  Are there better options that can be done with a minimal amount of work/learning?</p>
  
  <p>Thanks in advance for any suggestions you might have.</p>
  
  <p>Darvis</p>