Many ISPs provides shared connection through Cable internet to maximum utilisation of their resources & bandwidth. When number of users increases the speed of connection get down. You need a dedicated and high speed connection. There are also losses due to copper or coaxial cable. I suggest you to choose BSNL Fiber internet connection as its the fastest broadband connection in India. Optical fiber cable is extended upto your home from their exchange. Losses are minimum and speed is very high. However they are available only in Big & medium cities.
Here is the list of Fiber internet plans.http://telecomgk.com/bsnl-ftth-plans/