Speed up BSNL Dataone
may be this is an old trick
Steps to speed up BSNL Dataone/Broadband Internet :
1. Open Control Panel -> Networking and Sharing Center -> Manage Network Connection.
2. Now a window showing all networks will be opened. Select BSNL Connection -> Right click -> Properties.
3. Now, double click on Internet Protocol Version(TCP/IPv4) and in newly opened window at bottom, select “Use the following DNS Server address” .
4. And fill these 2 DNS Addresses in two fields:
208.67.222.222
208.67.220.220
and hit OK. Thats it. Your BSNL Internet Broadband DNS Servers changed.
enjoy 
or
4.4.4.1
4.2.2.2 

Free Public DNS Server
Service provider: ScrubIt
Public dns server address:
* 67.138.54.100
* 207.225.209.66
Service provider:dnsadvantage
Dnsadvantage free dns server list:
* 156.154.70.1
* 156.154.71.1
Service provider:OpenDNS
OpenDNS free dns server list:
* 208.67.222.222
* 208.67.220.220
Service provider: vnsc-pri.sys.gtei.net
Public Name server IP address:
* 4.2.2.1
* 4.2.2.2
* 4.2.2.3
* 4.2.2.4
* 4.2.2.5
* 4.2.2.6