This paper describes the creation of the tool to approach to models of dispersion of pollutants, framed under a methodology of software development, which identified the sequence to follow in the life cycle extension development, through an incremental model in which the stages of the project were identified. At each stage a series of activities that helped define inputs and outputs in each was made. According the above in the first stage the functional requirements defined and nonfunctional, then in stage two architecture and graphical interface, followed by the coding stage extension and finally the stage of performance testing and user, in order to improve or correct the functionality of the extension.
Web security issues remain a major challenge with numerous security concerns, Distributed Denial of Service Attack (DDos) leads among these. It was evolved from DOS and its main purpose is to consume large amount of server resources so that the server cannot provide service to normal users. Attackers usually gain access to large number of computers by exploiting the vulnerabilities to set up attack armies (i.e., Botnets). This paper will review and analyse different existing DDoS detecting techniques against different parameters, and propose a new hybrid architecture for the defence mechanism of DDoS attack.