Firewall: A firewall is software used to maintain the security of a private network. Firewalls block unauthorized access to or from private networks and are often employed to prevent unauthorized Web users or illicit software from gaining access to private networks connected to the Internet. A firewall may be implemented using hardware,

For a list of ports for each client deployment method, see Ports used during Configuration Manager client deployment. For more information about how to configure Windows Firewall on the client for client installation and post-installation communication, see Windows Firewall and port settings for clients. Ports used by migration Network firewall or proxy server settings for Zoom – Zoom Network firewall or web security gateway. If your app stays in a "connecting" mode or timed out due to "Network error, please try again" or "Can't connect to our service, please check your network connection and try again" - it could be related to your network connection, network firewall settings or web security gateway settings. What is Azure Firewall? | Microsoft Docs The Azure Firewall SNAT port utilization metric may show 0% usage even when SNAT ports are used. In this case, using the metric as part of the firewall health metric provides an incorrect result. This issue has been fixed and rollout to production is targeted for May 2020. Why do you need a firewall? | Adaware

What is a WAF? | Web Application Firewall explained

Firewall software are filters that stand between a computer or computer network and the Internet. Each firewall can be programmed to keep specific traffic in or out. All messages passing through the firewall software are examined. Those messages that do not meet pre-defined security criteria are blocked. What is a Firewall? - Computer Hope

Optimize performance with Azure Web Application Firewall deployed with Azure Front Door. Increase throughput for your global users with edge load balancing and application acceleration. Optimize your web app for high availability and scalability—with built-in auto-scaling and zone redundancy.

What Is a Firewall? - Cisco