First you should be well aware of the issue.1. type 192.168.1.1 in browser and hit enter . ( username : admin , pass : admin ) there, check Downstream data rate.. which should be 4096 or near by 4000.. If not.. it is clear that your plan in not upgraded...and if it is.. according to TRAI Quality of Service , an ISP should provide/maintain 80% of the promised speed. so, 80% of 4Mbps is 3.2 Mbps.. you should atleast get this speed.. Tell them briefly and make them understand..