One key characteristic of client/server databases is the limited amount of network traffic involved. Many applications using Microsoft® SQL Server™ allow the user to log in over a modem link and still use the application effectively. Although network I/O performance is reduced by a factor of 1,000 compared to a local area network (LAN), you often see little performance degradation. However, if large amounts of data are transferred between the client and the server, network performance can be affected.
It is a good idea to monitor the traffic between your client applications and the server. An application designed and tuned for slow networks works great on a fast network, but the opposite is not true. If you use a higher-level development tool that generates Transact-SQL statements and issues queries and updates on your behalf, it is especially important to keep on eye on what is going across the network.