RCDA: Recoverable Concealed Data
Aggregation for Data Integrity in
Wireless Sensor Networks
Chien-Ming Chen, Yue-Hsun Lin, Ya-Ching Lin,
Hung-Ming Sun
IEEE Transactions on Parallel and Distributed
Systems, Vol.23, No.4, April 2012
Presenter: 林顥桐
Date: 2012/11/19
1
Outline
•
•
•
•
•
•
Introduction
Encryption Scheme and Signature Scheme
RCDA Scheme for Homogeneous WSN
RCDA Scheme for Heterogeneous WSN
Implementation and Comparisons
Conclusion
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Introduction
• The usage of aggregation functions is
constrained
• The base station cannot verify the integrity
and authenticity of each sensing data
3
Introduction
• RCDA
– The base station can verify the integrity and
authenticity of all sensing data
– The base station can perform any aggregation
functions on them
4
Encryption Scheme and Signature
Scheme
• Encryption Scheme
– Mykleton et al.’s Encryption Scheme
• Signature Scheme
– Boneh et al.’s Signature Scheme
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Encryption Scheme and Signature
Scheme
• Mykleton et al.’s Encryption Scheme
– Proposed a concealed data aggregation scheme
based on the elliptic curve ELGamal(EC-EG)
cryptosystem
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Encryption Scheme and Signature
Scheme
• Boneh et al.’s Signature Scheme
– Proposed an aggregate signature scheme which
merges a set of distinct signatures into one
aggregated signature
– Based on bilinear map
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Outline
•
•
•
•
•
•
Introduction
Encryption Scheme and Signature Scheme
RCDA Scheme for Homogeneous WSN
RCDA Scheme for Heterogeneous WSN
Implementation and Comparisons
Conclusion
8
RCDA Scheme for Homogeneous WSN
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RCDA Scheme for Homogeneous WSN
• Four procedures
– Setup
• Base Station(BS) generates the key pairs
– Encrypt-Sign
• Trigger while a sensor decides to send its sensing data to the
cluster head(CH)
– Aggregate
• Launched after the CH has gathered all ciphertext-signature
pairs
– Verify
• Receive the sum of ciphertext and signature from CH, BS can
recover and verify each sensing data
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RCDA Scheme for Homogeneous WSN
• Setup
– (PSNi , RSNi ): For each sensor SNi, the BS
generates (PSNi,RSNi) by KeyGen Public key, where vi = xi*g
procedure(Boneh scheme) where PSNi = vi and
RSNi = xi Privacy key , randomly selected from Zp
– (PBS, RBS): These keys are generated by KeyGen
procedure(Mykletun scheme) where PBS ={Y, E, p,
G, n} and RBS = t
Y = t*G, E is an elliptic curve over a finite Fp, p is a prime number,
G is a generator on E, n is the order of E, t is a privacy key
randomly from Fp
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RCDA Scheme for Homogeneous WSN
• Setup
– RSNi, PBS, H, are loaded to SNi for all i
– BS keeps all public keys PSNi and its own RBS in
privacy
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RCDA Scheme for Homogeneous WSN
• Encrypt-Sign
Boneh’s signature
Mykleton’s Encrypt
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RCDA Scheme for Homogeneous WSN
• Aggregate
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RCDA Scheme for Homogeneous WSN
• Verify
– 1)
– 2)
– 3)
– 4)
?
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Outline
•
•
•
•
•
•
Introduction
Encryption Scheme and Signature Scheme
RCDA Scheme for Homogeneous WSN
RCDA Scheme for Heterogeneous WSN
Implementation and Comparisons
Conclusion
16
RCDA Scheme for Heterogeneous WSN
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RCDA Scheme for Heterogeneous WSN
• Five procedures
– Setup
• Necessary secrets are loaded to each H-Sensor and L-Sensor
– Intracluster Encrypt
• Involve when L-Sensor desire to send their sensing data to the
corresponding H-Sensor
– Intercluster Encrypt
• Each H-Sensor aggregates the received data and then encrypts and
signs the aggregated result
– Aggregate
• If an H-Sensor receives ciphertexts and signatures from other HSensor on its routing path, it activates the Aggregate procedure
– Verify
• Ensure the authenticity and integrity of each aggregated result
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RCDA Scheme for Heterogeneous WSN
• Setup
– (RHi, PHi ): the BS generates this key pair for each
H-Sensor according to KeyGen(Boneh’s scheme),
i.e., RHi = xi and PHi = vi
Privacy key , randomly selected from Zp
Public key, where vi = xi*g
– (RBS, PBS): This key pair is generated by
KeyGen(Mykletun’s scheme), i.e., PBS = {Y, E, p, G,
n} and RBS = t
Y = t*G, E is an elliptic curve over a finite Fp, p is a prime number,
G is a generator on E, n is the order of E, t is a privacy key
randomly from Fp
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RCDA Scheme for Heterogeneous WSN
• Setup
– The BS loads PBS to all L-Sensors. Each H-Sensor is
loaded its own key pair (PHi, RHi), PBS, and several
necessary aggregation functions
– Each L-Sensor is required to share a pairwise key
with its cluster head
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RCDA Scheme for Heterogeneous WSN
• Intracluster Encrypt
– Ensure the establishment of a secure channel
between L-Sensors and their H-Sensor
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RCDA Scheme for Heterogeneous WSN
• Intercluster Encrypt
– After collecting all sensing data from all cluster
members, an H-Sensor performs the prefered
aggregation function on these data as its result
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RCDA Scheme for Heterogeneous WSN
• Intercluster Encrypt
Boneh’s signature
Mykleton’s Encrypt
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RCDA Scheme for Heterogeneous WSN
• Aggregate
– If H3 receives (c1, ) from H1 and (c2, ) from
H2, H3 will execute this procedure to aggregate
(c1, ), (c2, ) and its own (c3, ) as follows:
– Finally, H3 sends (
) to H5.Similarly, H5 can
also aggregate (c4, ), (c5, ), and (
) then
get a new aggregated result (
) to the BS
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RCDA Scheme for Heterogeneous WSN
• Verify
– 1)
– 2)
– 3)
– 4)
?
25
Outline
•
•
•
•
•
•
Introduction
Encryption Scheme and Signature Scheme
RCDA Scheme for Homogeneous WSN
RCDA Scheme for Heterogeneous WSN
Implementation and Comparisons
Conclusion
26
Implementation and Comparisons
• Implementation
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Implementation and Comparisons
• Comparisons
– RCDA-HOMO has worst performance evaluation,
because RCDA-HOMO provides better security
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Conclusion
• The base station can securely recover all
sensing data rather than aggregated results
• Integrate the aggregate signature scheme to
ensure data authenticity and integrity in the
design
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