如果睇過舊po可以skip:
即時通訊軟件 – 你應該揀邊個?
Signal: [Unlike Telegram,] we never started turning over user data to HK police. Also, we don't have user data to turn over.
https://web.archive.org/web/20200807112716/https://twitter.com/signalapp/status/1280166087577997312
Signal 話 “我們唯一知道的信息是用戶的註冊日期和時間,以及用戶最近連接到Signal服務的日期”
https://signal.org/bigbrother/eastern-virginia-grand-jury/
Signal 被好多歐美嘅記者使用, 反而Telegram唔多人用: https://freedom.press/news/how-do-newsrooms-get-their-news-tips-we-reviewed-over-80-news-outlets/; 美國嘅一個NGO, The Committee to Protect Journalists 叫人咪用Telegram, 因為 Telegram by default 無 enable end-to-end encryption (E2EE), group chat更加係完全無得用E2EE
WhatsApp 同 Facebook Messenger 嘅 Secret Chat 都係使用Signal Protocol, Telegram嘅 MTProto encryption protocol卻係備受批評。https://cpj.org/blog/2016/05/why-telegrams-security-flaws-may-put-irans-journal.php
WhatsApp 嘅backup都係 plaintext;尤其如果您用咗Google Cloud 或 iCloud會變相完全繞過 end-to-end encryption, 所有message嘅內容可以被送中。 Telegram全部 message一開波就upload 曬上去 Telegram 嘅 servers
Signal 係由個非牟利機構運作, 冇 paid features, 廣告 / trackers。WhatsApp 同 Telegram都要賺錢, Telegram app有 Google 同 Microsoft trackers
Signal 俾你選擇是否:
1. 在訊息發送一段時間後自動毀滅所有 recipients 嘅 copy (disappearing messages),
2. 限制所有 recipients 只能看一次 disappearing media,
3. 當一個 conversation 傳送了一定數量的新訊息後, 自動 delete 你嘅舊訊息 (message trimming)
4. Relay calls through Signal servers
我建議您用即棄嘅預繳 SIM 卡 / 網上嗰啲 temporary number 嚟註冊 Signal, 記得enable Registration Lock
任何E2EE通訊軟件嘅伺服器必須被假定係惡意或 compromised 嘅, 因為如果訊息會因為servers被compromised就唔再係端對端加密嘅話,姐係話伺服器可以完全睇晒所有訊息, 咁從來都唔係 end-to-end encryption, 最多只係HTTPS (encryption in transit). Zoom 之前exactly就係咁呃過大家