only 100 users can access my website at a time after processing 100 request i need to access another 100 requests (users) and so on how can we do it?

Question

Hai,
 
   Q::- only 100 users can access my website at a time after processing 100
request i need to access another 100 requests (users) and so on how can we do
it?

Plz send appropriate apporach for this

Thanks

------------------------------------------------------------------------------
--