DIFFERENT TYPE OF FIREWALLS

PROXY FIREWALL
A proxy firewall is an early type of firewall device that acts as a gateway across networks for a specific application. Proxy servers can provide additional features like content caching and security by prohibiting direct connections from outside the network. However, this may have an influence on throughput capacities as well as the applications that can be supported.

STATEFUL INSPECTION FIREWALL
A stateful inspection firewall, often known as a "traditional" firewall, admits or denies traffic based on its state, port, and protocol. It watches all activity from the time a connection is opened until it is closed. Filtering decisions are based on both administrator-defined rules and context, which refers to the use of information from prior connections and packets from the same connection.

UNIFIED THREAT MANAGEMENT FIREWALL
A UTM device often loosely integrates the capabilities of a stateful inspection firewall, intrusion prevention, and antivirus. It may also incorporate extra services, such as cloud management. UTMs emphasize simplicity and ease of usage. 

NEXT GENERATION FIREWALL
Firewalls have progressed beyond basic packet filtering and stateful inspection. Most businesses are installing next-generation firewalls to protect against modern threats such as sophisticated malware and application-layer attacks.

Gartner, Inc. defines a next-generation firewall as one that includes:

Intelligent access control with stateful inspection
Integrated Intrusion Prevention System (IPS)
Application awareness and control to identify and ban dangerous applications
Upgrade pathways to incorporate future information feeds.
Techniques for addressing evolving security threats
URL filtering by geography and reputation

While these features are gradually becoming the norm in most businesses, NGFWs can do more.

THREAT FOCUS NEXT GENERATION FIREWALL
These firewalls have all of the characteristics of a typical NGFW, plus sophisticated threat detection and remediation.

With threat-focused NGFW, you can:

Complete context awareness allows you to identify which assets are most at danger.
Respond quickly to assaults with sophisticated security automation that sets policies and dynamically hardens your defenses.
Improve detection of evasive or suspicious activity by correlating network and endpoint events.
Reduce the time from detection to cleanup with retrospective security that continuously watches for questionable activity and behavior even after initial inspection.
Unified policies that protect throughout the full threat continuum make administration easier and less complex.