Post on 04-Apr-2018
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7/29/2019 Data Integrity Proofs in Cloud Storage [Pruthviraj]
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DATAINTEGRITYPROOFSINCLOUDSTORAGE
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CLOUDSTORAGE
Cloud storage is a service model in which data ismaintained, managed and backed up remotely and
made available to users over a network (typically
the Internet).
It allows users to upload files that could then be
accessed over the internet from a different
computer, tablet, smart phone or other networked
device, by the same user or possibly by other
users, after a password or other authentication isprovided.
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http://en.wikipedia.org/wiki/Tablet_computerhttp://en.wikipedia.org/wiki/Smart_phonehttp://en.wikipedia.org/wiki/Smart_phonehttp://en.wikipedia.org/wiki/Tablet_computer7/29/2019 Data Integrity Proofs in Cloud Storage [Pruthviraj]
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CLOUDSTORAGE
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CloudStorage
Provider
Client
Storage server
Web server
Pros:
Lower cost
Easier management
Enables sharing andaccess from anywhere
Cons:
Loss of control
No guarantees of data
availability Provider failures
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DATA INTEGRITY PROOFSIN CLOUD STORAGE
Cloud storage moves the users data to large data centers,
which are remotely located, on which user does not have any
control.
However, this unique feature of the cloud poses many new
security challenges which need to be clearly understood andresolved.
One of the important concerns that need to be addressed is to
assure the customer of the integrity i.e. correctness of his data
in the cloud.
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EXISTING SYSTEM:
The simplest Proof of retrivability (POR) scheme
can be made using a keyed hash function hk(F). In this scheme the verifier, before archiving the data
file F in the cloud storage, pre-computes the
cryptographic hash of F using hk(F) and stores this
hash as well as the secret key K.
To check if the integrity of the file F is lost the
verifier releases the secret key K to the cloud
archive and asks it to compute and return the value
of hk(F).
By storing multiple hash values for different keys
the verifier can check for the integrity of the file F
for multiple times, each one being an independent
proof. 5
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DISADVANTAGES:
Though this scheme is very simple and easily
implementable the main drawback of this scheme
are the high resource costs it requires for the
implementation.
At the verifier side this involves storing as many
keys as the number of checks it want to perform as
well as the hash value of the data file F with each
hash key.
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PROPOSED SYSTEM:
We present a scheme which does not involve the encryption
of the whole data.
We encrypt only few bits of data per data block thus reducing
the computational overhead on the clients.
The client storage overhead is also minimized as it does not
store any data with it. Hence our scheme suits well for thin clients.
In our data integrity protocol the verifier needs to store only a
single cryptographic key - irrespective of the size of the data
file F- and two functions which generate a random sequence.
The verifier does not store any data with it.
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Architecture:
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SPOT-CHECKING
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CloudStorage
Provider
Client
F B4 B7 T1 T2 T3B1 T1B1
Small corruptions
go undetected
k
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ERRORCORRECTINGCODE
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CloudStorage
Provider
Client
F
Parity blocks
Corrects
small
corruption
k
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ADVANTAGES:
it a reliable solution to the problem of avoiding local
storage of data
We encrypt only few bits of data per data block thus
reducing the computational overhead on the clients.
The client storage overhead is also minimized as it
does not store any data with it.
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By :
PRUTHVI RAJ