This is a very broad level questions. Can you please elaborate the specifics you are looking out for? As handling large data is contextual based on what you are trying to achieve.
For .e.g you may using WCF RIA Services which will be used by Silverlight clients. In this case, you can make use of MTOM (Message Transmission Optimization Mechanism) for transfering huge data.
Before going that route, how big is your data? These attributes needs to be defined.
If you can be more specific then that would help you get some good responses.
Rajesh Pillai, Mar 08, 2011