Chapter 5 Configuring Virtual Sensors

Normalization and Inline TCP Evasion Protection Mode

•Virtual Sensor—All packets with the same session key (AaBb) within a virtual sensor belong to the same session. This is the default and almost always the best option to choose.

Normalization and Inline TCP Evasion Protection Mode

Note For the ASA IPS modules (ASA 5500-X IPS SSP and ASA 5585-X IPS SSP), normalization is performed by the adaptive security appliance and not the IPS.

Normalization only applies when the sensor is operating in inline mode. The default is strict evasion protection, which is full enforcement of TCP state and sequence tracking. The Normalizer enforces duplicate packets, changed packets, out-of-order packets, and so forth, which helps prevent attackers from evading the IPS.

Asymmetric mode disables most of the Normalizer checks. Use asymmetric mode only when the entire stream cannot be inspected, because in this situation, attackers can now evade the IPS.

HTTP Advanced Decoding

HTTP advanced decoding facilitates analysis of encoded HTTP return web traffic by using on-the-fly decoding. Changes to HTTP advanced decoding take effect immediately and only affect the new traffic flows.

Restrictions

The following restrictions apply when you enable HTTP advanced decoding:

•Although HTTP advanced decoding does not fire any new signatures, drop packets, or modify traffic, it allows existing signatures to match on content that was previously not detectable because of encodings.

•HTTP advanced decoding only acts on return web response traffic.

Caution Enabling HTTP advanced decoding severely impacts system performance.

Note Because HTTP advanced decoding requires the Regex card and the String XL engine, it is available only to those platforms that have them. HTTP advanced decoding is supported on the IPS 4345, IPS 4360, IPS 4510, IPS 4520, ASA 5585-X IPS SSP, ASA 5525-X IPS SSP, ASA 5545-X IPS SSP, and

ASA 5555-X IPS SSP.

Adding, Editing, and Deleting Virtual Sensors

This section describes how to add, edit, and delete virtual sensors, and contains the following topics:

•Adding Virtual Sensors, page 5-5

•Editing and Deleting Virtual Sensors, page 5-9

Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2

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Cisco Systems IPS4510K9 manual Normalization and Inline TCP Evasion Protection Mode, Http Advanced Decoding, Restrictions
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IPS4510K9 specifications

Cisco Systems has long been a leading player in network security, and its IPS (Intrusion Prevention System) series is a testament to its commitment to safeguarding digital environments. Among its notable offerings are the IPS4510K9 and IPS4520K9 models, both designed to provide advanced threat protection for mid-sized to large enterprise networks.

The Cisco IPS4510K9 and IPS4520K9 are distinguished by their cutting-edge features that help organizations defend against a myriad of cyber threats. These systems utilize a multi-layered approach to security, integrating intrusion prevention, advanced malware protection, and comprehensive visibility across the network.

One of the primary characteristics of the IPS4510K9 is its high performance. It boasts a throughput of up to 1 Gbps, making it suitable for environments that demand rapid data processing and real-time responses to threats. The IPS4520K9, on the other hand, enhances that capability with improved throughput of up to 2 Gbps, accommodating larger enterprises with heavier network traffic. These models are equipped with powerful processors that support complex signature matching and can intelligently distinguish between legitimate traffic and potential threats.

In addition to performance, both models are designed with scalability in mind. They can be easily integrated into existing Cisco infrastructures. This facilitates a seamless enhancement of security without causing significant interruptions to ongoing operations. Moreover, they offer flexible deployment options, allowing organizations to operate them inline or out of band depending on their specific needs.

The Cisco IPS4510K9 and IPS4520K9 leverage advanced detection technologies, utilizing a variety of signature types and heuristic analysis to detect known and unknown threats effectively. They are equipped with real-time alerting and reporting capabilities, giving security teams immediate visibility into potential breaches and enabling them to respond swiftly.

Furthermore, both models support a range of management options through the Cisco Security Manager, allowing for centralized administration, streamlined policy management, and enhanced monitoring capabilities. Automated updates ensure the systems remain current with the latest threat intelligence, vital for staying ahead of evolving cyber threats.

In summary, the Cisco Systems IPS4510K9 and IPS4520K9 represent powerful solutions for organizations seeking robust intrusion prevention capabilities. With their high performance, scalability, and advanced detection technologies, these systems are essential tools in the ever-changing landscape of cybersecurity, providing enterprises with the peace of mind needed to operate securely in today's digital world.
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