In a Security Operations Center (SOC), network monitoring plays a major role in detecting and preventing cyberattacks.
Here are the top 15 network security and attack-related interview questions and answers

Q.1 What are the main layers of the OSI model relevant to SOC monitoring?

The OSI model (Open Systems Interconnection) has 7 layers, but the most relevant ones for SOC monitoring are:

  • Layer 3 – Network Layer: Handles IP addressing and routing (used for detecting IP-based attacks).
  • Layer 4 – Transport Layer: Manages communication using TCP and UDP (used for identifying port scans, DoS attacks).
  • Layer 7 – Application Layer: Focuses on user applications like HTTP, DNS, and SMTP (used to detect phishing, data exfiltration, or malware communication).

Q.2 What is DNS tunneling and how can it be detected?

DNS tunneling is a technique where attackers hide data inside DNS queries to bypass firewalls and send stolen data to a remote server.

Detection Methods:

  • Monitor for unusually long DNS queries.
  • Look for high volume of DNS requests to unknown domains.
  • Analyze DNS traffic patterns with SIEM or IDS tools.

Q.3 What is lateral movement and how do you detect it?

Lateral movement is when an attacker moves from one compromised system to another inside a network to reach sensitive data or servers.

Detection:

  • Check for unusual authentication between systems.
  • Monitor use of administrative tools like PsExec, RDP, or PowerShell.
  • Look for login attempts from unexpected devices or accounts.

Q.4 What is privilege escalation and how is it performed by attackers?

Privilege escalation happens when attackers gain higher permissions than intended — like turning a normal user account into an admin.

Types:

  • Vertical Escalation: Gaining higher privileges.
  • Horizontal Escalation: Accessing other users’ data.

Common Methods:

  • Exploiting unpatched software.
  • Misconfigured permissions.
  • Stealing admin credentials.

Q.5 What are common signs of data exfiltration?

Data exfiltration means stealing data from a system and sending it out of the network.

Signs:

  • Large outbound traffic at unusual hours.
  • Data being sent to unknown or external IPs.
  • Abnormal use of encryption or compression tools.
  • Multiple failed login attempts followed by large data transfers.

Q.6 What are command-and-control (C2) communications?

C2 communications allow attackers to remotely control infected systems through commands sent over the internet.

Detection:

  • Monitor unusual outbound connections to unknown IPs or domains.
  • Watch for repeated communication patterns at regular intervals.
  • Use threat intelligence feeds to block known C2 servers.

Q.7 What are common network-based attacks (e.g., MITM, ARP spoofing)?

Common Attacks:

  • MITM (Man-in-the-Middle): Attacker intercepts communication between two systems.
  • ARP Spoofing: Sends fake ARP messages to redirect traffic.
  • DDoS (Distributed Denial of Service): Overloads servers with fake traffic.
  • DNS Poisoning: Redirects users to malicious websites.

Q.8 How can you identify abnormal network traffic?

Methods:

  • Establish a baseline of normal network activity.
  • Use SIEM or IDS tools to spot deviations.
  • Look for unusual bandwidth use or connections to rare ports.
  • Monitor geo-location anomalies (traffic from unexpected countries).

Q.9 What are endpoint security tools commonly used in SOC?

Endpoint security tools protect computers and devices from threats.
Common ones include:

  • Antivirus/Anti-malware: Windows Defender, McAfee, Bitdefender.
  • EDR (Endpoint Detection and Response): CrowdStrike, SentinelOne, Carbon Black.
  • DLP (Data Loss Prevention): Symantec, Forcepoint.

Q.10 What is EDR?

  • EDR stands for Endpoint Detection and Response.
    It’s a security solution that monitors endpoints — like laptops, desktops, servers, and mobile devices — for suspicious or malicious activities.
  • Think of EDR as a smart security guard sitting on every computer in your organization, continuously watching what’s happening, detecting anything strange, and responding before the attacker causes serious damage.

Q.11 What Are Endpoints?

Endpoints are any devices that connect to your network, such as:

  • Laptops and desktops
  • Servers
  • Mobile devices
  • Virtual machines
  • Cloud workloads

Attackers often target endpoints because they are easier to access than secured servers.

Q.12 How do you analyze firewall logs for suspicious activity?

Firewall logs record all network traffic allowed or blocked by the firewall.

Steps:

  1. Identify traffic from unusual IPs or countries.
  2. Look for multiple failed connection attempts.
  3. Detect spikes in traffic or unusual port access.
  4. Correlate events with SIEM alerts.

Q.13 What is Risk Management in SOC?

Risk management in SOC means identifying, analyzing, and minimizing the cybersecurity risks that can harm an organization’s systems, data, and operations.

Q.14 How Do You Measure the Effectiveness of SOC Operations?

Measuring the effectiveness of SOC operations means checking how well the team detects, responds to, and prevents cyber threats. It’s done using key metrics like Mean Time to Detect (MTTD) and Mean Time to Respond (MTTR). A lower detection and response time shows better performance. Regular reviews, audits, and attack simulations also help ensure the SOC is efficient and continuously improving.

Q.15 What is Threat Hunting?

Threat Hunting is the proactive search for hidden cyber threats in your network or systems.
Unlike waiting for alerts to show up, threat hunters actively look for suspicious activity that may have bypassed your security tools.

Think of it like a detective searching for criminals before they commit a crime, instead of waiting for an alarm after the crime has happened.

Key Points:

  • It is proactive, not reactive.
  • Uses tools like SIEM, EDR, and network logs.
  • Relies on patterns, behavior analysis, and threat intelligence.

Conclusion

Network security is the foundation of every SOC operation.
Understanding these 15 questions will not only help you clear interviews but also strengthen your real-world analytical skills in detecting and responding to network-based attacks.