What port/protocol combination is used for the DNS block/allow rules in pfBlockerNG?

What port/protocol combination is used for the DNS block/allow rules in pfBlockerNG?

• A. TCP 53
• B. UDP 80
• C. UDP 443
• D. UDP 53

Answer: (D)

DNS queries primarily use port 53 and most of them travel over UDP because the requests and responses are small and fast. pfBlockerNG’s DNS block/allow rules are built around this standard path, filtering traffic destined to or from UDP port 53 to control which domain lookups are permitted or blocked. While DNS can use TCP on occasions (for large responses or zone transfers), the typical and most relevant traffic for filtering is UDP 53, so that’s the correct combination. Ports 80 and 443 are for web traffic, not DNS, so they aren’t used for DNS filtering.

DNS queries primarily use port 53 and most of them travel over UDP because the requests and responses are small and fast. pfBlockerNG’s DNS block/allow rules are built around this standard path, filtering traffic destined to or from UDP port 53 to control which domain lookups are permitted or blocked. While DNS can use TCP on occasions (for large responses or zone transfers), the typical and most relevant traffic for filtering is UDP 53, so that’s the correct combination. Ports 80 and 443 are for web traffic, not DNS, so they aren’t used for DNS filtering.