Home Router Firewall Configuration

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• All home routers come with at least a basic firewall
• some allow advanced filtering rules
• Any firewall operates two types of filtering:
  • inbound filtering
    • determines whether remote hosts can connect to given TCP/UDP ports on internal hosts
    • On a home router, all inbound ports are blocked by default
    • Exceptions to this default block are configured via port forwarding
  • outbound filtering
    • determines the hosts and sites on the Internet that internal hosts are permitted to connect to
    • On a home router, outbound connections are allowed by default
      • can be selectively restricted via a content filter
• Any packet-filtering firewall can allow or block traffic based on source and destination IP address filtering
  • Identifying which IP address ranges should be allowed or blocked and keeping those lists up to date is a complex task
  • Most home router firewalls implement content filtering instead
    • firewall downloads curated reputation databases that associate IP address ranges, FQDNs, and URL web addresses with sites known to host various categories of content and those associated with malware, spam, or other threats
    • filters can also block URLs or search terms using keywords and phrases
    • There will be separate blocklists for different types of content that users might want to block
  • can also restrict the times at which the Internet is accessible
    • configured in conjunction with services offered by the ISP

Content filtering is a security measure performed on email and Internet traffic to identify and block suspicious, malicious and/or inappropriate content in accordance with an organization’s policies.