CCNA 200-301 NGFW & IPS Concepts

CCNA 200-301: NGFW & IPS

Next-Generation Firewalls (NGFW)

Role in the Network

An NGFW is an advanced type of firewall that moves beyond traditional port/protocol inspection. Its primary role is to provide a deeper level of network security by inspecting traffic at the application layer (Layer 7). This allows it to enforce security policies based not just on IP addresses, but on applications, users, and content, offering more granular control and better protection against modern threats.

NGFW conceptual diagram

Key Functions & Features

  • Application Awareness and Control: Identifies and controls traffic based on the specific application (e.g., block Facebook but allow Salesforce), regardless of the port or protocol used.
  • Deep Packet Inspection (DPI): Examines the actual data within packets, not just the headers, to identify malicious code or content.
  • Integrated Intrusion Prevention System (IPS): Includes IPS functionality to actively detect and block network exploits and attacks in real-time.
  • Stateful Inspection: Maintains context of network connections, just like traditional firewalls, to ensure that returning traffic is legitimate.
  • Threat Intelligence Integration: Often connects to cloud-based threat intelligence services to stay updated on the latest malware, malicious domains, and attack vectors.
  • User Identity Awareness: Can integrate with services like Active Directory to enforce policies based on user roles and groups, not just IP addresses.

Intrusion Prevention Systems (IPS)

Role in the Network

An IPS is a dedicated security device or software that actively monitors network traffic for malicious activity and policy violations. Unlike an Intrusion Detection System (IDS) which only logs and alerts, an IPS is placed inline with traffic and can take immediate, automated action to prevent an attack from succeeding. Its role is to be the active enforcer against known and unknown network threats.

IPS conceptual diagram

Key Functions & Detection Methods

  • Signature-Based Detection: The most common method. It compares network traffic against a database of known attack signatures (like an antivirus scanner for the network).
  • Anomaly-Based Detection: It first establishes a baseline of "normal" network behavior and then flags and blocks any deviations from that baseline, which can help catch new, unknown attacks (zero-day attacks).
  • Policy-Based Detection: Administrators can define specific security policies, and the IPS will block any traffic that violates these rules.
  • Automated Threat Response: When a threat is detected, an IPS can take several actions, such as dropping malicious packets, blocking traffic from the source IP address, or resetting the connection.