Firewalling Basics: Difference between revisions
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== 44Net Connect and Security == | == 44Net Connect and Security == | ||
44Net Connect provides every device with a public facing IPv4 address, and does not inspect, filter, or block any traffic directed towards 44Net devices. Devices with publicly routable IP addresses face a constant barrage of traffic from various scanners and bots on the internet. Some of them are malicious, and | 44Net Connect provides every device with a public facing IPv4 address, and does not inspect, filter, or block any traffic directed towards 44Net devices. Devices with publicly routable IP addresses face a constant barrage of traffic from various scanners and bots on the internet. Some of them are malicious, and correctly configuring your firewall is a key part of defending against them. | ||
== What does a firewall do? == | |||
At its most basic, a firewall inspects incoming and outgoing packets, and based on its set of rules, decides whether each packet should be allowed through, dropped, or diverted. Rules may consider a packet's source and destination IP, source and destination interface, port, protocol (TCP vs UDP), or various special flags that may be set. Basic firewall usage is primarily concerned with source/destination IP, source/destination interface, and port. There are several goals we can achieve via firewall rules: allow outside connections to public-facing services, block outside connections to private services, and in case your device is compromised, block outgoing malicious traffic originating from your device. | |||
=== Stateful vs Stateless Firewalls === | |||
== Low Level Tools: iptables and nftables == | == Low Level Tools: iptables and nftables == | ||
Revision as of 21:57, 21 July 2026
44Net Connect and Security
44Net Connect provides every device with a public facing IPv4 address, and does not inspect, filter, or block any traffic directed towards 44Net devices. Devices with publicly routable IP addresses face a constant barrage of traffic from various scanners and bots on the internet. Some of them are malicious, and correctly configuring your firewall is a key part of defending against them.
What does a firewall do?
At its most basic, a firewall inspects incoming and outgoing packets, and based on its set of rules, decides whether each packet should be allowed through, dropped, or diverted. Rules may consider a packet's source and destination IP, source and destination interface, port, protocol (TCP vs UDP), or various special flags that may be set. Basic firewall usage is primarily concerned with source/destination IP, source/destination interface, and port. There are several goals we can achieve via firewall rules: allow outside connections to public-facing services, block outside connections to private services, and in case your device is compromised, block outgoing malicious traffic originating from your device.