I am using the REST framework in Java with restlet api for my web service. If 100,000 users send web service requests, how do I do this? Please can anyone suggest me an idea to handle 100,000 requests for a REST web service?
You need to run the web service on multiple servers to avoid performance gains. You can also use cloud computing (for example, amazon micro instance .. its free) and a load balancer to balance the load on each server.
One suggestion is to use a load balancer and reduce the load on one server.
This question is too important to answer. There are many aspects to writing an application that scales well. Books such as Scaling Rules help highlight different areas that you can work on. Databases / Application Servers / Cache / Status and some things to consider. No one can give you a concrete answer to this question.