1. Privacy preserving secure dataPrivacy preserving secure data
exchange in mobile P2Pexchange in mobile P2P
cloud healthcare environmentcloud healthcare environment
Sk. Md. Mizanur Rahman · Md. Mehedi Masud
M. Anwar Hossain · Abdulhameed Alelaiwi ·
Mohammad Mehedi Hassan · Atif Alamri
Received: 2 October 2014 / Accepted: 6 February 2015
© Springer Science+Business Media New York 2015
Dhaka University of Engineering and Technology, Gazipur
Presented by
Md. Mostafijur Rahman
Masters Student ID #: 132431(p)
Department of Computer Science and Engineering

2. Outline of the talkOutline of the talk
• P2P cloud
o Technology context: multi-core, virtualization, 64-bit processors, parallel
computing models, big-data storages…
• Describes the related work
• Elaborates on the privacy and security threats, which can occur
when cloud peers exchange data over an unsecured channel
and highlights our contribution.
• Secure data exchange : we describe how the data exchange
policy/mapping is established between two cloud peers for our
proposed protocol
• Pairing-based cryptography , we discuss issues of cryptographic
implementation and prevention of different attacks in the
proposed anonymous secure data exchange protocol.
• Anonymous authentication
Dhaka University of Engineering and Technology, Gazipur

3. ABSTRACTABSTRACT
• Cloud computing technology offers the possibility of inter
organizational medical data sharing at a larger scale. The
different organizations can maintain their own cloud
environment while exchanging healthcare data among
them in a peer-to-peer(P2P) fashion according to some
defined polices.
• Our proposed solution allows cloud peers to dynamically
generate temporary identities that are used to produce a
session key for each session of data exchange.
• Protocol is robust against different attacks, such as target-
oriented, man-in-the middle, masquerade, and message
manipulation attacks.
Dhaka University of Engineering and Technology, Gazipur

4. Operation WorkOperation Work
In this paper we propose an anonymous on-the-fly secure data
exchange protocol for such environment based on pairing-based
cryptography. The proposed solution does not require a centralized
control for the peers and it can avoid the expensive Public Key
Infrastructure (PKI) based approach.
The proposed scheme allows cloud peers to dynamically generate
temporary identities that are used to produce a session key for each
session of data exchange. It is robust against different security
attacks, such as target-oriented, man-in-the middle, masquerade,
and message manipulation attacks.
Hospital, clinics, medical laboratories, pharmacists, and other
stakeholders) are willing to share and exchange data about
patients’ treatments, medications, and test results
over an insecure network such as the Internet.
Dhaka University of Engineering and Technology, Gazipur

5. OperationOperation
Fig. 1 An example model of a collaborative healthcare scenario using P2P-Cloud-DB architecture
Dhaka University of Engineering and Technology, Gazipur

6. Operation healthcare scenario of a P2POperation healthcare scenario of a P2P
Dhaka University of Engineering and Technology, Gazipur
In this scenario, family doctors (FDDB), hospitals (HDB), medical laboratories
(LABDB), pharmacies (PHDB), and other stakeholders (e.g. medical research cells
(RDB)) are willing to exchange or coordinate information about patients’
treatments, medications, test results, and diseases.
In the system, an organization (a cloud peer) may need to be exchange data with
other related organizations (cloud peers) according to some established policies
between them. For example, family doctors may want to keep track of patients’
medications for some specific diseases. Therefore, FDDB should have a link with
the PHDB.
Any patient in PHDB diagnosed with a disease that is of interest to family doctors
may have data that needs to be exchanged with FDDB. Moreover, family doctors
may be interested in collecting test results of their patients from LABDB and the
medications that their patients take while staying at hospitals and hence a link
between FDDB and HDB is required. The links between cloud peers in the figure
are formally a set of mappings or mapping constraints.

7. Anonymous DynamicAnonymous Dynamic
Pseudo-ID generation techniquePseudo-ID generation technique
in P2P-Cloud-DBin P2P-Cloud-DB
Dhaka University of Engineering and Technology, Gazipur
Figure Above : In this paper, we propose an anonymous secured data
exchange protocol between cloud peers where cloud peers generate
dynamic IDs and the corresponding session keys on-the-fly for data
exchange based on the requested query. In our protocol, when two cloud
peers want to exchange data, each of them generates its dynamic ID and
the corresponding secret session key using the shared attributes between
them by computing a pairing function over an elliptic curve. Then the
cloud peers authenticate each other in a challenge and response fashion.

8. Key agreement & anonymous secure data exchange in P2PKey agreement & anonymous secure data exchange in P2P
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9. OperationOperation
Dhaka University of Engineering and Technology, Gazipur
Step-by-step procedure of the Proposed Protocol
STEP 1: A query Qt is generated at the target Pj .
STEP 2: Target Pj determines group G1, hash functions
H1 and H2 and performs the following steps:
2.a: Generates a dynamic temporary ID
TIDP , a dynamic authentication code
MACCA∧∨NCAj→i and a random number Rj .
2.b: Pj sends < G1,H1,H2,Rj, TIDP MACCA∧∨NCAj→i > to the source Pi .
STEP 3: Source Pi generates MACCA NCAi,∧∨ θ
; 1 ≤ θ ≤ n and compares with MACCA NCAj→i .∧∨
If any one of MACCA NCAi,∧∨ θ matches with
MACCA NCAj→i then∧∨

10. OperationOperation
Dhaka University of Engineering and Technology, Gazipur
3.c: Generates a secret session key KSi, and an authentication code Aut0.
3.d: Sends < G2, ˜ e,H3, TIDPi , RPii−SESSION , Aut0 > to the target Pj .
STEP 4: Target Pj generates secret session key KSj , and verification code V er0.
4.a: Generates a random number RPjj−SESSION .
4.b: Compares V er0 with Aut0 if V er0 =
Aut0 then generates Aut1.
4.c: Sends < RPjj−SESSION,Aut1 > to the source Pi .
STEP 5: Source Pi generates verification code V er1.
5.a: Compares V er1 with Aut1 if V er1 = Aut1 then generates message authentication
code MACMESSAGE.
5.b: Encrypts query result QRt, with session key KSi denoted as CIPHERQRt
.5.c: Sends < TIDPi ,CIPHERQRt , MACMESSAGE, TIDPj > to the target Pj .
STEP 6: Target decrypts CIPHERQRt with session key KSj ; generates verification message
authentication code VERMESSAGE; compares VERMESSAGE with MACMESSAGE. if
VERMESSAGE = MACMESSAGE then data is accepted.

11. Anonymous secure data exchange inAnonymous secure data exchange in
P2P-Cloud-DB DurationP2P-Cloud-DB Duration
Dhaka University of Engineering and Technology, Gazipur

12. RISKS ASOCIATED WITHRISKS ASOCIATED WITH
CLOUDCLOUD
• Privacy threat : Procedures are being developed to improve
security and performance in the cloud.
• Masquerade attack : Malicious peer may pretend to be a valid
target of a source by stealing the identity of the real target.
• Man-in-the-middle attack : Shim proposed an improved identity-
based authenticated key agreement protocol by including certified
public keys. The author claims that the protocol provides attractive
security properties, such as, known-key security, forward secrecy, key
compromise impersonation resilience, and unknown key-share
resilience.
• Message manipulation attack : For this attack, an attacker needs to
take part in the message communication. To this end, it is necessary
to be a valid node in the network. In our protocol, an attacker
cannot forge the data exchange session and data packet as was
already discussed.
Dhaka University of Engineering and Technology, Gazipur

13. RESEARCH ISSUESRESEARCH ISSUES
•Define the characteristics of an application under test and the
types of testing done on the application. providing all this in a
cost-effective manner?
•Evaluate whether certain testing infrastructure in the cloud really
helps to meet a specific performance attribute.
•Validate the quality of cloud tested applications at all levels. .
•Management of test data
Dhaka University of Engineering and Technology, Gazipur

14. SummarySummary
•In this paper, we have presented a novel privacy preserving :
•Secure data exchange protocol for a P2P cloud environment in a health care
domain. Using this protocol a peer in a P2P-Cloud-DB generates a dynamic
temporary ID .
•Fly and corresponding session key by exchanging some system and session
parameters with other peers. The protocol is based on pairing-based cryptographic
model where the generated system and session parameters are derived from the
confidential and non-confidential attributes that are present in the data schema of
the P2P-Cloud-DB.
•An important feature of the proposed protocol is that peers always generate a new
dynamic temporary ID and a corresponding session key based on the query
initiated by a target peer and authenticate themselves anonymously without
disclosing their IDs. Thus, every session is completely independent with respect to the
ID and session key generation.
• Hence the proposed protocol successfully prevents different attacks such as man-
in-the-middle attack, masquerade attack, message manipulation attack, and the
more sophisticated target oriented attack. This approach has the potential to bring
confidence into P2P cloud database system in case of anonymous secure data
exchange in the health care domain.
Dhaka University of Engineering and Technology, Gazipur

15. References & useful linksReferences & useful links
• 1. Fuxman A, Kolaitis PG, Miller RJ, Tan WC (2005) Peer data
exchange. In ACM Trans Database Syst 31(4):1454–1498
• 2. Beeri C, Vardi MY (1984) A proof procedure for data
dependencies. In JACM 31(4):718–741
• 3. Halevy AY, Ives ZG, Suciu D, Tatarinov I (2003) Schema
mediation in peer data management system. In: Proceedings
of the international conference on data engineering, pp 505–
516
Dhaka University of Engineering and Technology, Gazipur

16. Section Questions and AnswersSection Questions and Answers
ThanksThanks
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