Firewall 🟢 Protection

👉 Firewall types

By technology

• Packet filtering firewall analyses packet headers (IP addresses, ports, protocols).
• State-inspected firewall tracks the status of active connections to make context-sensitive decisions.
• Proxy firewall acts as an intermediary between the user and the Internet (e.g. application proxy).
• Next Generation Firewall (NGFW) Includes advanced functions (DPI, IPS, application detection)

By deployment

• Hardware firewall Dedicated physical appliance (e.g. Cisco ASA).
• Software firewall installed on an OS (e.g. Windows Defender).
• Cloud firewall protects cloud infrastructures (e.g. AWS WAF).
• UTM firewall (Unified Threat Management): combined firewall, antivirus, VPNetc.

How it works

• Filtering applies rules (allow/block) based on IP addresses, ports, etc.
• In-depth inspection (NGFW): analyses the content of packets to detect threats.
• Logging Traffic logger: records traffic for auditing and analysis.
• Connection management maintains a status table of active sessions.

Examples of firewalls

Software firewalls :

• Windows Defender Firewall (integrated into Windows)
• iptables (Linux)
• Third-party solutions: Norton, ZoneAlarm, Comodo

✔ Advantages of software firewalls :

• More flexible and configurable
• Less costly for small structures
• Can be installed on any appliance

Hardware firewalls :

• Cisco ASA, Firepower
• Palo Alto PA-Series
• Fortinet FortiGate
• SonicWall Network Security Firewalls
• Firewalls integrated into consumer routers (e.g. Netgear, TP-Link)

✔ Advantages of hardware firewalls :

• Protects the entire network
• High performance
• Does not consume server resources

📊 Key figures

World :

• Firewall market estimated at USD 4.1 billion in 2023 (source: Gartner).
• 95 % companies use a firewall (Cybersecurity Ventures).
• Market leaders: Cisco (23 % market share), Palo Alto (19 %), Fortinet (15 %).

France :

• 85 % of SMEs/ETIs equipped with a firewall (ANSSI, 2023).
• Local players: Orange Cyberdefense, Thales.