Mozambique Tyre Tracking - RFID tags, RFID readers, RFID ...
Intl. Conf. on Computers, Privacy & Data Protection Pi b D ......Shamir Tags IllustratedShamir Tags...
61
Intl. Conf. on Computers, Privacy & Data Protection Pi b D i Privacy by Design Marc Langheinrich University of Lugano (USI) Switzerland
Transcript of Intl. Conf. on Computers, Privacy & Data Protection Pi b D ......Shamir Tags IllustratedShamir Tags...
Intl. Conf. on Computers, Privacy & Data Protection
P i b D iPrivacy by Design
Marc LangheinrichUniversity of Lugano (USI)
Switzerland
NON PRIVACY BY NON DESIGNExample 1
NON PRIVACY BY NON DESIGN
2006
20 cards20 cards
no encryption
C dh ld ‘ NCardholder‘s NameCard Number
Expiration DateExpiration Date
2008
C dh ld ‘ NCardholder‘s NameCard Number
Expiration DateExpiration Date
*MacBook Air not included
2008
Non Privacy By Non Designy y g
NON PRIVACY BY BAD DESIGNExample 2
NON PRIVACY BY BAD DESIGN
P<D<<LANGHEINRICH<<MARC<<<<<<<<<<<<<<<<<<<<<123456789?D<<710123?M070101?<<<<<<<<<<<<<<<?123456789?D<<710123?M070101?<<<<<<<<<<<<<<<?
Protection from Forgery!!Protection from Forgery!!
Digital Signature
„ ...cloned and manipulated... “
MustermannChristian
?Christian0000000000000
?Proof of Genuine Passport ?
Non Privacy By Bad Designy y g
PRIVACY BY DESIGN?Example 3
PRIVACY BY DESIGN?
Smart Fridgeg
Smart Stove
Receiptless Returns
Fast Checkout
WhiggModel #2342
Material: PolyesterTiger Tanga
Maker: Aldi (Suisse)Last washed: 5 days ago
ViagraLabo
rato
ries
Maker: PfitzerSize: Maxi (60 pills)
2006
Ari
Juel
s, R
SA
D-M
an”
Art
wor
k (c
) O
rigi
nal “
RFID
Working Hypothesis
People don‘t wantPeople don t want privacy toolsprivacy tools
People want toPeople want to get things done!get things done!The more secure, private, safe, the better
Getting ThingsGetting Things Done?Done?
Vision
Hands Free PrivacyHands Free Privacy
The more secure, private, safe, the better
Example: The Shamir TagExample: The Shamir Tag
Langheinrich, Marti: Practical Minimalist Cryptography for RFID Privacy. IEEE Systems Journal, Vol. 1, No. 2, 2007
Example: The Shamir TagExample: The Shamir Tag
• Unsolicited read outs take long time• Unsolicited read-outs take long time–Difficult (but not impossible) to track
or identify
• Instant Identification for known tags• Instant Identification for known tags–Owner uses tags without restrictions
Langheinrich, Marti: Practical Minimalist Cryptography for RFID Privacy. IEEE Systems Journal, Vol. 1, No. 2, 2007
Shamir Tags IllustratedShamir Tags Illustrated
Original d bOriginalRFID-Tag:
RFID-Tag contains encrypted ID + Key, but cut in many small pieces. All pieces are needed to decrypt Tag ID.
Shamir Tags IllustratedShamir Tags Illustrated
Original d bOriginalRFID-Tag:
RFID-Tag contains encrypted ID + Key, but cut in many small pieces. All pieces are needed to decrypt Tag ID.
UnknownReader sees:
wait wait wait
Only few shares disclosed A few more shares disclosed Still not enough shares…
titime
Shamir Tags IllustratedShamir Tags Illustrated
Original d bOriginalRFID-Tag:
RFID-Tag contains encrypted ID + Key, but cut in many small pieces. All pieces are needed to decrypt Tag ID.
UnknownReader sees:
wait wait wait
Owner‘s
Only few shares disclosed A few more shares disclosed Still not enough shares…
+ =Owner‘sReader sees:
Owner checks for Instant IdentificationOnly few shares disclosed Owner checks forknown (cached) tag
y
Consumers receive basicprotection for all tagged goods
Additional security mechanism ycan be layered above Shamir Tags
Summary
Privacy by DesignPrivacy by Design
• Difficult to do even for technology expertsDifficult to do even for technology experts– Industrial (RFID Credit Cards)
Government (ePassport)– Government (ePassport)
• Difficult if wrong user model– People want to get things done
– Privacy, security often gets in the way
• We need usable security and privacy– Sometimes less security may mean more privacy
