this study aims at investigating the impacts of mandatory audit firm rotation (mafr) on audit fees and audit market compeition among firms listed on tehran stock exchange (tse). since 2007 firms listed on tse are not allowed to use services of any single audit firm for more than 4 consecutive years. we tested our hypotheses using multivariate regression analysis and mean comparison test. our sa...

A packet dropping and message tampering attack contains data which routed between source and destination. Packet dropping attack happens accidently or deliberately on network or packet switching network. Message tampering attack causes measure problem in message transmission activity, due to unauthorized party tampered message and can change message contains so it hard to detect that tampered m...