A Flexible Read-Write Abortion Protocol with Sensitivity of Roles

In information systems, illegal information flow among objects has to be prevented. A transaction illegally and suspiciously reads an object if the object includes data in other objects which are not allowed to be read and the object is suspicious, respectively. A transaction illegally and impossibly writes an object after illegally and suspiciously reading an object, respectively. In this paper, we discuss the flexible read-write-abortion with role sensitivity (FRWA-R) protocol where a transaction is aborted with some probability once illegally reading an object. The abortion ratio depends on the sensitivity of roles which the transaction holds. The sensitivity of a role shows how many transactions which holds the role are aborted after illegally reading an object. The more number of roles to which illegal information flow for a role occur, the lower sensitive the role is. A transaction with lower sensitive roles which illegally reads an object is aborted with higher probability. In the evaluation, we show the execution time of each transaction in the FRWA-R protocol is shorter than the WA protocol and more number of reads can be performed than the RWA protocol.