The video below shows how we placed requests to a domain name server inside Sri Lanka Telecom network to resolve a few domain names.Many other SLT nameservers we tested have the same behaviour, so it is clear it’s not this specific one. This video only shows one of them.
The domain name server with IP address 22.214.171.124 is hosted in the Government network and shows how it resolves correctly the google.lk and bbc.co.uk domains but fails to resolve colombotelegraph.com.
The bogus responses (IP address 127.0.0.1) when requesting colombotelegraph.com or www.colombotelegraph.com is a common response when implementing domain name filtering. Many other SLT DNS servers have the same behaviour, in the video, only 1 of them is shown.
We have created this video so others can reproduce the test to verify our claims.
Not all SLT users are affected because:
1) Maybe not all the SLT nameservers have this behaviour (many of those we tested send the bogus responses).
2) Some SLT users do not use the SLT nameservers (knowingly or not, for example if their computer or some equipment in their network use other DNS like Opendns).
Click here to watch the video if you cannot view it
Click here to read the history of blocking Colombo Telegraph