Cloud storage moves user data to remote data centers that users do not control, posing new security challenges. The document proposes a scheme using hash-based message authentication codes and RSA signatures to allow users to verify the integrity of their cloud data, addressing problems of data integrity and security. It aims to reduce costs for clients with limited resources to check data integrity in the cloud.

2.  Cloud storage moves the user’s 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 and resolved.
 We provide a scheme which gives a proof of data integrity
in the cloud which the customer can employ to check the
correctness of his data in the cloud.

3.  As data generation is far outpacing data storage it proves
costly for small firms to frequently update their hardware
whenever additional data is created. Also maintaining the
storages can be a difficult task. It transmitting the file across
the network to the client can consume heavy bandwidths.
 Cloud storage moves the user’s data to large data
centers, which are remotely located. However, this
uniquefeature of the cloud poses problems like data
integrity, data security etc.

4.  The main drawback of this scheme is the high resource
costs it requires for the implementation.
 Also computing hash value for even a moderately large data
files can be computationally burdensome for some clients
(PDAs, mobile phones, etc).
 Data encryption is large so the disadvantage is small users
with limited computational power (PDAs, mobile phones etc.).

5.  We propose a remote data integrity checking protocol
based on HLAs and RSA signature with the support public
verifiability.
 It is important to note that our proof of data integrity
protocol checks the integrity of data i.e. if the data has
been illegally modified or deleted.

6.  The support of public verifiability makes the protocol very
flexible.
 User can deploy a TPA to check the data integrity.
 By reducing the costs of storage, maintenance and
personnel.
 It reduces the chance of losing data by hardware failures.
 Not cheating the owner.

7.  Cloud computing provides new economies for information
technologies as well as new challenges. Properly
constructed, it can be more secure than traditional IT
infrastructure, but that construction requires the use of
strong, integrated and usable security mechanisms.
 Thus our proposed system can be used for ensuring the
integrity of data stored in cloud data storage devices.
 It will be an added advantage to all Cloud users.