Disclosed is a computer-based technology for handling end-to-end business transactions in a TCPIP-environment. Since cooling water flows fast in the shallow water channel, it is possible to improve a cooling efficiency and also reduce pressure loss using a deep water channel with deep cavities. The security device may also determine a risk score based on the likelihood score and the impact score, where the risk score provides an indication of a risk that the security event will affect the customer network. The back haul device having the short haul communication means and a wireless telephonic communication means. This allows the local UI-server to retrieve a user-session-image for a user-session from a user-session-image repository.