Abstract CAPTCHA perhaps, the most known security issue among the general users. Web users have awareness about the security use of it for which no fundamental education is required. The usability elements in CAPTCHA are addressed in this work. We have used the disc CAPTCHA for an experimental analysis. We did it by contacting some two hundred users from many regions through... CAPTCHA perhaps, the most known security issue among the general users. Web users have awareness about the security use of it for which no fundamental education is required. The usability elements in CAPTCHA are addressed in this work. We have used the disc CAPTCHA for an experimental analysis. We did it by contacting some two hundred users from many regions through online. We have collected the data and analysed it with interesting results. Read More Read Less

Abstract Distributed Denial of Service is a normal type of security attack for which network protection is deployed. Network resources are aimed by this attack which is now studied. We have used a solution named as DenfensePro for safeguarding the network resources. We have tested the efficiency of the introduced solution for network resources protection.... Distributed Denial of Service is a normal type of security attack for which network protection is deployed. Network resources are aimed by this attack which is now studied. We have used a solution named as DenfensePro for safeguarding the network resources. We have tested the efficiency of the introduced solution for network resources protection. Read More Read Less

Abstract The paper describes the practices for protection of information, control systems and assets by transmission system operators (TSOs) in the region of South-East Europe (SEE). Based on a survey undertaken among the TSOs of the SEE region, the paper indicates state of the art practices and future developments related to critical infrastructures in electricity transmission networks.... The paper describes the practices for protection of information, control systems and assets by transmission system operators (TSOs) in the region of South-East Europe (SEE). Based on a survey undertaken among the TSOs of the SEE region, the paper indicates state of the art practices and future developments related to critical infrastructures in electricity transmission networks. Read More Read Less