Let us assume that the given input set of characters for the URL is n and the length of the URL can vary from to 1 to k. Now we will have k clusters handling URLs of k different sizes varying from 1 to k. Each cluster maintains a Distributed Hash Table called as the URL Cluster Table having all string patterns from the input set of characters n of size k (varying from 1 to k for first to k numbered cluster) as unique keys and the corresponding value as whether the URL Identification Service visited the web resource or not. Here maintaining different clusters for different sizes of URLs helps us in maintaining dynamic black list of URLs of different lengths separately per cluster.