Tools for Building an OCA (Occasionally Connected Application)

Question

I will be building an in-house, Occasionally Connected App (OCA). What technologies would you suggest I employ.

Here are my parameters:

1. .NET Shop(3.5sp

Answer 1

Once you solve the problem of change detection and data movement, everything else is trivial. In other words technologies like WPF, Silverlight, Forms and even WCF are orthogonal to your main problem and your choice should be based on your personal preferences and experience. The real hard nut to crack is working disconnected and synchronizing changes. Which leaves two out-of-the-box avenues: Synch Framework or Replication.

I would say, for your scenario, definetely Synch Framework. Merge replication, like all forms of replication, is designed for systems that are connected continously with intermitent disconnects. And most critically replication can work only over static names. Laptops connecting from various hot-spots and ISPs have a nasty habit of changing FQ names with each connection. Replication can overcome this only if a VPN of sort is used and VPN is usually a major support issue. Replication is just not designed for the high mobility of OCA systems.

Synch Framework will pretty much force you to SQL 2008 back end because of the need to Change Data Capture or Change Tracking, both being SQL 2008 only features.

You will still have plenty of hard problems to solve ahead (authentication, versioning and upgrade, data conflict resolution policies, securing data on the client for accidental media loss etc etc)