The Practice of Network Security Monitoring – You’re compromised, so deal with it. #security #bookreview

The Practice of Network Security Monitoring

Understanding Incident Detection and Response
Richard Bejtlich
(No Starch Press – paperback, Kindle)

Security expert Richard Bejtlich’s focus in his new book is not on “the planning and defense phases of the security cycle.” Instead, he emphasizes how to handle “systems that are already compromised or that are on the verge of being compromised.”

His well-organized, well-written, 341-page book aims to help you “start detecting and responding to digital intrusions using network-centric operations, tools, and techniques.”

Bejtlich has long emphasized a “detection-centered philosophy” built around a straightforward central tenet: “Prevention eventually fails.” No matter how many digital walls and moats you build around your network, someone will find a way to tunnel in, parachute in, or sneak in via an unsuspecting employee’s $9.95 thumb drive.

“It’s becoming smarter,” he writes, “to operate as though your enterprise is always compromised. Incident response is no longer an infrequent, ad-hoc affair. Rather, incident response should be a continuous business process with defined metrics and objectives.”

You may recognize some of Bejtlich’s previous books on network security monitoring (NSM): The Tao of Network Security Monitoring; Extrusion Detection; and Real Digital Forensics.

The Practice of Network Security Monitoring is tailored toward two key audiences: (1) security professionals who have little or no experience with NSM; and (2) “more senior incident handlers, architects, and engineers who need to teach NSM to managers, junior analysts, or others who may be technically less adept.”

Readers, he add, should understand “the basic use of the Linux and Windows operating systems, TCP/IP networking, and the essentials of network attack and defense.”

The examples in Bejtlich’s book rely on open source and vendor-neutral tools, primarily from Doug Burks’ Security Onion (SO) distribution.

The 13-chapter book is organized into four parts:

• Part I: Getting Started – Introduces NSM and sensor placement issues.
• Part II: Security Onion Deployment – Shows how to install and configure SO.
• Part III: Tools – Examines the “key software shipped with SO and how to use these applications.”
• Part IV: NSM in Action – Looks at “how to use NSM processes and data to detect and respond to intrusions.”

Following the technical chapters, Bejtlich offers some concluding thoughts on network security management, cloud computing, and establishing an effective workflow for NSM. “NSM isn’t just about tools,” he writes. “NSM is an operation, and that concept implies workflow, metrics, and collaboration. A workflow establishes  a series of steps that an analyst follows to perform the detection and response mission. Metrics, like the classification and count of incidents and time elapsed from incident detection to containment, measure the effectiveness of the workflow. Collaboration enables analysts to work smarter and faster.”

He also observes: “It is possible to defeat adversaries if we stop them before they accomplish their mission. As it has been since the early 1990s, NSM will continue to be a powerful, cost-effective way to counter intruders.”

— Si Dunn