Concerned to Developing Download Accelerator using Visual C#

Question

I want to develop a Download Accelerator using Visual C# (.Net framework 2.0) to increase the speed of downloading process as compared to default downloading process.The algorithm behind this is, splitting a file that is to be downloaded into several parts & then accessing all those parts simultaneously.
So,please tell me  which Namespace,Classes,Methods will be use for this apllication.And how to split the file into several parts & accessing them simultaneously.