iMAP Myanmar 2023 Internet Censorship Report | Page 34 Blocking of Instant Messaging Apps From 1 July 2022 to 30 June 2023, OONI measurements were done for four instant messaging apps. Total Measurements Facebook Messenger Signal Telegram Whatsapp 15,538 7,854 15,505 15,461 21.1% 10.1% 46.7% Percentage of blocked and likely blocked 61.4% Note: Failed measurements are discarded from this table. ● The Facebook messenger test showed a lot of anomalies with failed DNS lookups and failed TCP connections through 39 ASNs. But it was sometimes accessible. ● Most Signal tests were found reachable on 38 ASNs. Some results show that the anomaly presented signs of blocking. ● Almost all Telegram tests reported continued access on 40 ASNs during the testing period. It is likely to be blocked in a few days. ● The measurements of WhatsApp test on 40 ASNs show that WhatsApp had signs of potential blocking but was accessible from some vantage points on some days. Blocking of Circumvention Tools Psiphon Tor Tor Snowflake Vanilla Tor 15,590 Total Measurements 15,313 4,710 4,640 Percentage of 2.6% blocked and likely blocked 7.9% 8.0% 0.0% Note: Failed measurements are discarded from this table. ● For almost the entire research period, Psiphon worked in the tested network through 32 ASNs and could be used to circumvent internet censorship. ● Nearly all Tor tests described that Tor worked on 31 ASNs in Myanmar during the testing period. ● According to test results, Tor Snowflake mostly worked on 21 ASNs to circumvent censorship. ● Tor (Vanilla) tests showed that the Tor network was reachable from 21 vantage points in Myanmar.