are usually passive devices and can be deployed into existing networks with little or no disruption to normal network operations.

NIDPSs

Explanation:

A network-based IDPS (NIDPS) has many strengths, but these strengths are also often its weaknesses. A NIDPS strength is that the system reassembles content and analyzes the data against the security policy in the format the target would process it. Another strength is that the data is processed passively, out of band of regular network traffic. A related strength is that a NIDPS can be centrally located on the network at a choke point to reduce hardware costs and configuration management. However, all of these benefits also introduce pitfalls, which will be discussed serially. Furthermore, there are some difficulties that any IDPS suffers from simply due to the fact that the Internet is noisy, and so differentiating security-related weird stuff from general anomalies becomes exceptionally difficult

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