摘要: A "blocker" tag is a privacy-enhancing radio-frequency identification (RFID) tag. It operates by interfering with the protocol in which reader communicates individually other RFID tags. While inexpensive to manufacture quantity, blockers are nonetheless special-purpose devices, and thus introduce level of complexity that may pose an obstacle their deployment.We propose variant on blocker concept we call soft blocking. This involves software (or firmware) modules offer different balance characteristics than ordinary blockers. Soft blocking offers somewhat weaker privacy enforcement essentially voluntary or internally auditable (much like P3P). has significant advantage, however, relying standard very slightly modified) Additionally, possibility flexible policies partial scrubbed data revealed about "private" tags, lieu all-or-nothing policy enforced blocker.We show, moreover, how correct functioning soft-blocker system be rendered externally minor modifications basic tag-reading protocol. We also briefly discuss special, attractive approach unblocking, soft-blocking permits "opt-in" consumer privacy.