How do you conduct network security forensics in a team?

1 Define the scope and objectives

Before you start any network security forensics activity, you need to define the scope and objectives of your investigation. This will help you narrow down the sources, types, and locations of the data you need to collect and analyze. You also need to establish the legal and ethical boundaries of your investigation, such as the consent, authorization, and privacy of the data owners and subjects. Moreover, you need to align your objectives with the expectations and requirements of your stakeholders, such as your clients, managers, or law enforcement agencies.

2 Assign roles and responsibilities

Network security forensics is a multidisciplinary field that requires different skills, knowledge, and expertise. Therefore, it’s important to assign roles and responsibilities to your team members according to their qualifications, experience, and availability. Common roles in network security forensics include the lead investigator who oversees the entire investigation and coordinates the team; the data collector who gathers data from network devices, systems, and traffic; the data analyst who examines the data for patterns, anomalies, and indicators of compromise; and the data presenter who prepares and presents the findings and recommendations of the investigation.

3 Follow a standard methodology

Network security forensics is a systematic process, with four main phases: preparation, collection, analysis, and presentation. Each phase has specific steps, procedures, and guidelines to ensure data and findings are valid, reliable, and intact. Common standards and frameworks for network security forensics include ISO/IEC 27037 for digital evidence collection and preservation, NIST SP 800-86 as the US national guideline for network forensic analysis, and RFC 3227 as the internet engineering task force guideline for evidence handling.

4 Use appropriate tools and techniques

When performing network security forensics, you need to select tools and techniques that match your scope, objectives, and data sources. Factors to consider include compatibility with network devices and systems, functionality for effective and efficient tasks, accuracy of results that can be verified and validated, as well as security of the network and data. All of these elements are essential for successful network security forensics.

5 Document and report everything

Network security forensics is not only about collecting, analyzing, and presenting data; it's also about documenting and reporting everything you do and find during the investigation. This is essential for accountability, transparency, reproducibility, and communication. Documentation and reporting demonstrate that you followed the standard methodology and legal/ethical principles, disclosed assumptions/limitations/uncertainties of data/findings, can reproduce data/findings using same/similar tools/techniques, and can communicate data/findings clearly/convincingly to stakeholders.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?