nel using IPsec. Before entering a security zone data contents of the traffic flow may be controlled at security inspection points. In these points there may be a firewall, a filtering router or even an IP security end-point aimed at control data integrity and privacy. The existence of security policies, covering not only IT security, but general corporate security is essential to assure the system integrity. Security violations frequently come from sources not usually taken into account, such as employees' information, trivial or unchanged passwords, and even physical security attacks. Security violation attempts have to be alarmed, reported and consistently analysed in order to prevent future damages. Integration between the telecom management alarm and performance management and the global security systems should be desirable although it is not always feasible. 16.9 QoS MANAGEMENT The rather crowded Figure 16.23 exemplifies some of the ongoing initiatives and con- troversy around QoS. Delay and jitter are annoying to the end user for multimedia synchronous (isochronous) services, like voice or video. The associated and necessary QoS management consists mainly of: Admission policy (possibly shaping). Assignation of specific paths for isochronous real time traffic (preventing the competi- tion from long IP data packets). Prioritization (certain packets can be dropped in case of congestion). The isochronous traffic is identified at the entrance node (edge router or MGWs), eventually marked and allowed to flow through a special path, where the delay may be kept within acceptable values. Differentiation of traffic at certain entrance points is therefore a common procedure on modern networks. For all differentiation of traffic (quality, security etc.) there is a need for a policy. A policy server is a common solution. The server provides mapping facilities for services, business and network configuration concepts. QoS bearer service provision, secure tunnel configuration or IPsec configuration Telecom Management - O