Meta's engineering team details the cryptographic architecture behind Advanced Browsing Protection (ABP) in Messenger, which checks clicked links against a malicious URL database without revealing the queried URL to the server. The system combines Private Information Retrieval (PIR) with an Oblivious Pseudorandom Function
Table of contents
Private Information Retrieval – The Starting Point for ABPHow ABP Handles Prefix Queries for URLsPre-processing RulesetsSafeguarding Client QueriesThe ABP Request LifecycleSort: