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hack proofing your network second edition p10

Một giải pháp nhanh chóng quay đầu là sử dụng một công cụ Dremel hoặc khoan với một chút gỗ (như trục của một tăm bông cotton hoặc một cây tăm). Di chuyển khoan nhẹ dọc theo bề mặt epoxy sẽ làm suy yếu và mỏng vật liệu kết dính. | IDS Evasion Chapter 16 713 Summary Signature-based IDS sensors have many variables to account for when attempting to analyze and interpret network data. Many challenges continue to elude these systems. The lack of information that is available for inspection is difficult to overcome. However the rate at which many IDS sensors have been maturing is quite promising Gigabit speeds and flexible architectures supported by an evergrowing security community push forward to configure systems that are capable of detecting all but the most obtuse and infrequent attack scenarios. At every layer of the network stack there are difficulties with maintaining a consistent view of network traffic as well as the effect of every packet being transmitted. It is quite clear that an attacker has certain advantages being able to hide in a sea of information while being the only one aware of their true intension. Packet layer evasions have been well documented throughout the past several years. IDS vendors are quite aware of the many issues surrounding packet acquisition and analysis. Most networks are beginning to filter suspicious packets in any case that is any types with options and excessive fragmentations. Perhaps in the coming years network layer normalizations will become commonplace and many of these evasion possibilities will evaporate. The difficulty with analyzing the application layer protocols continues to cause ongoing headaches. Some proxy solutions have begun to take hold but the bottleneck that these systems cause is often too great.They also suffer from similar issues as IDSs unable to identify classes of attacks that they were not originally intended for. It is quite acceptable to quash malformed TCP IP packets in the case of an error a legitimate end system would eventually retransmit. The same is not true for higher layers a NIDS may have an extremely limited understanding of application protocols and the information they transmit. Polymorphic attacks present a .