A firewall’s main purpose is to build a fence (or “wall”) that classifies a private network from incoming external traffic (such as the internet) for the goal of blocking malicious network packets like malware and intrusions.
Next-Generation Firewalls (NGFW) or Unified Threat Management (UTMs) are a combination of various other defensive security strategies combined and provided as a bundle.
- Software-defined wide area networks (SDWAN).
- Gateway-Level Anti-Virus.
- Anti-Spam Filtering.
- Intrusion Prevention Systems (IPS).
- Intrusion Detection Systems (IDS).
- Secure Email Gateways.
- Stateful-Filtering Firewalls.
- Packet-Filtering Firewalls
- Web Application Firewalls.
- Dynamic Packet Filtering Firewalls.
- SSL VPNs or Virtual Private Networks.
A secure web gateway, on the other hand, has some firewall functionality but is not the same as a firewall and only focuses on outgoing web traffic (often restricted to ports 80 and 443
The proxy can act as a Firewall. However, Firewalls is not a proxy. Proxy firewalls, also known as application-level firewalls, filter network traffic at the application layer of the OSI network model. As an mediator between two systems, proxy firewalls monitor traffic at the application layer HTTP and FTP). To discover anomalies in the traffic, both stateful and deep packet inspection are leveraged.
VPNs encrypt traffic between devices so that the session can safely traverse public networks (usually over the Internet) and has been made virtually private.