Technical Issues in Library RFID Privacy

1
Technical Issues in Library RFID Privacy

• David Molnar
• UC-Berkeley
• Computer Science

2
What are we worried about?

• RFID new technology
• Law of unintended consequences
• Read tags through backpacks, briefcases
• Can we track books?
• track link sightings of same book
• Can we figure out what youre reading?
• Who we is depends
• FBI, marketers, teenagers, college students, pick
  your favorite

3
How RFID Works

• Radio Frequency IDentification
• Passive tags no power source
• Tag carries small amount of data
• May be read-only or limited read/write
• RFID reader powers tag, extracts data via radio

Power
Stored data
4
Two Main Questions

• How to read tags?
• What is on the tag?

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How to read tags?

• Need an RFID reader
• Standardization not privacy issue in long term
• Read range for 13.56Mhz tags low
• Ubiquity of readers bigger problem!
• Reader at door of every Starbucks?
• Blocking tag signals, kill, not sufficient
• Security Bit does not prevent tag read
• Read passwords?

6
What is on the tag?

• Varies by vendor and library decision
• Library bar code
• Unique, static ID ? can track book
• Need library database to learn title/author
• Unless see book later, learn bar code/title map
• Some vendors suggest more info
• The LibChip stores data such as type of
  material, title, author, bar code and serial
  number, shelf location, last borrowed date, and
  last returned date. Libramation site

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Encrypting Tag Data

• Several meanings to encrypting data
• Proprietary encoding, not different per library
• Buy reader from company or secondary market
• Eventually reverse engineered
• Encrypting bar code with per-library key
• Does not currently exist
• Non-library readers cant understand data
• Still leads to static data ? can track book

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Bottom Line

• Reading static ID is privacy risk
• Risk will grow as readers become cheaper, more
  available, more common
• Minimize data on tag
• No title, no author, etc. on tag
• Protect bibliographic database!
• Privacy depends on choices in deployment