Summary: Covering performance comparison of existing object-relational mapping on the database used in project in telecommunications business area. Demonstrated graphical comparison of performance on different types of requests.

Key words: SQL Server, databases, object-relational mapping, performance, Ado.Net. Entity Framework, NHibernate, LINQ2SQL, software.

Summary: Covering modern problems of hacker attacks on web applications. Giving detailed description of such attacks as dangerous redirections and links, attacks related on the user sessions manipulations and SQL injections. Examples include implementation on such programming languages ​​as Java, PHP, C# and Ruby.

Key words: Internet network, hacker, application security, software, browser, host dangerous redirect, links, SQL injection, database.