I have learned from the DE Proctoring Service that the web browsers installed on the computers in the testing centers will from now on be blocking access to search engines. This means that you will not be able to search the Internet during tests.
Websites other than search engines will not be blocked. So if you have a favorite math tool that you might want to use during a test, make sure you know the link to the tool BEFORE you go to the test center. You won't be able to search for the link during the test using a search engine.