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Friday, May 10, 2013

Secure of database

Database Security

Database security is a protection against destruction of data and use of data by users who do not have the authority. To maintain security Database, can be done in the following ways:· Determination Data Base Server software is reliable.· Granting authority to any user who has access, and manipulate the data available.Database security purposes:· Confidentiality· Integrity· AvailabilityThreats to the security of database· Interuption· Interception· Modification· FabricationMisuse Database:1. Not intentional, type:· Damage during the transaction process· Anomaly caused by concurrent database access· Anomaly caused by pendistribuasian data on multiple computers· Logic errors that threaten the ability to maintain the consistency of database transactions2. Incidentally, type:· Collecting data / data read by unauthorized parties· Conversion of data by unauthorized parties· Deletion of data by unauthorized partiesDepth In Database Security:1. Physical2. Human3. Operating System4. Database SystemsDatabase Security settings:1. AuthorizationGranting authority or privilege (privilege) to access the system or database objects to users who are responsible2. Table ViewTable view is a restriction method for users to obtain database models to suit individual needs. This method can be used to hide data or not needs to be seen by the user.3. Data backup and recoveryBackup is the process periodically to make copies of the database and do the logging file (or program) to external storage media.Recovery is an attempt to restore the database to the circumstances in which it is considered right after the occurrence of a failure.There are 3 types of recovery, among others:· Recovery for transaction failures: Unitary natural procedure program that can change / update the data on the number of tables.· Restoration of the failure of the media: media recovery because of failure by taking or returning a copy of the database load (backup)· Restoration of the failure of the system: Because the system disorder, hangs, electricity cut off the flow.Recovery facility in the DBMS:1. Periodic backup mechanism2. Logging facility by making tracks in place when the transaction took place and when the database changes.3. Checkpoint facility, the latest database update.4. Manager recovery, allow the system to restore the database to be more consistent after the occurrence of errorsRecovery Techniques:· Defered upate / pending changes: changes in DB will not take place until the transaction is on approved points (COMMIT). If there is a failure it will not change, but the redo surgery is needed to prevent a result of such failure.· Immediate Update / direct changes: changes to the DB will immediately without having to wait for a transaction is approved. In the event of failure of required UNDO operations to see if there is a transaction that has been approved prior to the failure.· Shadow Paging: using shadow page IMANA paa process consists of the same two tables, one is a transaction table and the other is used as a backup. When the transaction is started at the same table and the second during the last transaction table that stores all the changes to the database, the shadow table will be used if something goes wrong.The advantage is no need REDO or UNDO, weakness makes the fragmentation.4. Unity Data and Encryption· Encryption: data security· Integrity: methods of examination and validation of data (integrity constraint methods), which contains the rules or boundaries for the purpose of implementation of data integrity.· Concurrent: a mechanism to ensure that concurrent transactions on multiple user databases are not mutually interfere with the operation of each. The existence of accurate scheduling process (time stamping).