User manual SONY VAIO VGN-NW350F/S

[. . . ] Neither this manual, nor any of the material contained herein, may be reproduced without written consent of the author. Disclaimer The information in this document is subject to change without notice. The manufacturer makes no representations or warranties with respect to the contents hereof and specifically disclaim any implied warranties of merchantability or fitness for any particular purpose. The manufacturer reserves the right to revise this publication and to make changes from time to time in the content hereof without obligation of the manufacturer to notify any person of such revision or changes. Limitations of Liability UNDER NO CIRCUMSTANCES SHALL SONY OR ITS SUPPLIERS BE LIABLE FOR DAMAGES OF ANY CHARACTER (E. G. DAMAGES FOR LOSS OF PROFIT, SOFTWARE RESTORATION, WORK STOPPAGE, LOSS OF SAVED DATA OR ANY OTHER COMMERCIAL DAMAGES OR LOSSES) RESULTING FROM THE APPLICATION OR IMPROPER USE OF THE SONY PRODUCT OR FAILURE OF THE PRODUCT, EVEN IF SONY IS INFORMED OF THE POSSIBILITY OF SUCH DAMAGES. [. . . ] Intrusion Detection and Prevention 6. 3. 1. Overview Intrusion Definition Computer servers can sometimes have vulnerabilites which leave them exposed to attacks carried by network traffic. Worms, trojans and backdoor exploits are examples of such attacks which, if successful, can potentially compromise or take control of a server. A generic term that can be used to describe these server orientated threats are intrusions. Intrusion Detection Intrusions differ from viruses in that a virus is normally contained in a single file download and this is normally downloaded to a client system. An intrusion manifests itself as a malicious pattern of internet data aimed at bypassing server security mechanisms. Intrusions are not uncommon and they can constantly evolve as their creation can be automated by the attacker. NetDefendOS IDP provides an important line of defense against these threats. Intrusion Detection and Prevention (IDP) is a NetDefendOS module that is designed to protect against these instrusion attempts. It operates by monitoring network traffic as it passes through the D-Link Firewall, searching for patterns that indicate an intrusion is being attempted. Once detected, NetDefendOS IDP allows steps to be taken to neutralize both the intrusion attempt as well as it's source. IDP Issues In order to have an effective and reliable IDP system, the following issues have to be addressed: 1. What kinds of traffic should be analyzed?Most importantly, an IDP Rule specifies the Action to take on detecting an intrusion in the traffic targeted by the rule. Initial Packet Processing The initial order of packet processing with IDP is as follows: 1. A packet arrives at the firewall and NetDefendOS performs normal verification. If the packet is part of a new connection then it is checked against the IP Rule-set before being passed to the IDP module. If the packet is part of an existing connection it is passed straight to the IDP system. If the packet is not part of an existing connection or is rejected by the IP rule-set then it is dropped. The source and destination information of the packet is compared to the set of IDP Rules defined by the administrator. If a match is found, it is passed on to the next level of IDP processing which is pattern matching, described in step below. If there is no match against an IDP rule then the packet is accepted and the IDP system takes no further actions although further actions defined in the IP rule-set are applied eg. address translation, logging. 2. Checking Dropped Packets The option exists in NetDefendOS IDP to look for intrusions in all traffic, even the packets that are rejected by the IP Rule-set check for new connections, as well as packets that are not part of an existing connection. This provides the firewall administrator with a way to detect any traffic that appears to be an intrusion. With this option the only possible IDP Rule Action is logging. [. . . ] Website: www. dlink. co. il Italy LatinAmerica Luxemburg Middle East (Dubai) Via Nino Bonnet n. TEL: 39-02-2900-0676, FAX: 39-02-2900-1723. Website: www. dlink. it Isidora Goyeechea 2934, Ofcina 702, Las Condes, Santiago ­ Chile. Website: www. dlink. cl Rue des Colonies 11, B-1000 Brussels, Belgium TEL: +32 (0)2 517 7111, FAX: +32 (0)2 517 6500. [. . . ]