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Secure and Serverless RFID Au-thentication and Search Protocols

Chiu C. Tan, Bo Sheng, and Qun LiIEEE Transactions on Wireless Communication APRIL 2008

Taesung Kim2008.09.11

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Contents

• Abstract• Introduction• Related Work• RFID Privacy and Security• RFID Authentication• RFID Search

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Introduction

• What is Radio Frequency Identification?

Tag

Antenna

Reader

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Introduction

• Solution for RFID Security and Privacy problem– Central database model– Three players in this model

• RFID reader, tag, database– 리더와 태그의 상호인증에 database 에 저장된 인증정보를

이용– Database 와 연결이 없는 오프 사이트 위치에 있는 리더는

태그의 정보를 볼 수 없다 .• Simple alternative

– Downloading database to reader– Mobile reader can be stolen.– An adversary will have access to information which in-

clude unique tag id and password.– The adversary can make fake tag based on this informa-

tion.

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Introduction

• This paper suggest– Security protection as the central database model with-

out persistent connection to the database.• RFID searching problem

– Single reader, multiple tag 상황에서 특정 tag 의 정보를 검색하는 경우 .

– Authenticating each tag one at a time is a time consum-ing process.

• This paper suggest several solutions for RFID searching problem.

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Related Work

• Weis– randomized hash lock– Tag reply to reader query

• (r, ID⊕fk(r))– where r is a random number generated by the tag, – k is the tag’s secret key – and fk is a pseudorandom function.

• A secure database searches the ID/secret key, then the real tag ID returned to reader.

• Molnar and Wagner– Randomized hash lock scheme does not defend against

an eavesdropper.– Reader 가 secret key 를 알고 있다고 가정– Reader 와 tag 가 각각 random number 를 만들고 교환한다 .

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Related Work

– Tag reply• ID⊕fk(0, r1, r2)

– Compromised reader problem.• Dimitriou

– Tag reply• (h(IDi), nt, hIDi (nt, nr))

– where IDi is the tag secret.– nt, nr are both random nubers generated by tag and reader

• Database return hIDi+1(nt, nr)

• The tag update its screct IDi+1

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RFID Authentication

• Notations

CA Trusted party, responsible for authenticating readers and deploying tags

RiRFID reader i

riid for RFID reader Ri

Liaccess list for RFID reader Ri

n number of entries in Li

TiRFID tag i

idiid for RFID tag Ti

tisecret for RFID tag Ti

h(x) one-way hash function

f(x,y) Concatenate x and y, then applying h(.), h(x||y)

l number of bits of hash h(.)

m CA defined number of bits, m < l

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RFID Authentication

• Set up– R obtains r and L from a certificate authority, CA.– Tag, T contains a unique value id, a unique secret t.– Access List Li

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RFID Authentication

• Authentication Protocol

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RFID Search

• 특정 태그를 찾고자 할 때

• Reader issues a search request such that only au-thenticated tag can understand.

• The tag reply in such that only an authenticated reader can understand.

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RFID Search

• Secure search protocol

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RFID Search

• Search protocol improvement– Tag remember the last used random number.

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RFID Search

• Search protocol improvement– A challenge and response method

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RFID Search

• Search protocol improvement– A noise to mask the reply

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Thank you!