Networking ConceptsQuestion 4 of 100
What is the default port used by the Domain Name System (DNS) for standard name resolution queries?
a.TCP 25
b.TCP 110
c.UDP 67
d.UDP 53
Explanation
DNS uses UDP port 53 for most standard queries because they are small and benefit from low overhead. TCP 53 is used for zone transfers and larger responses. Ports 25, 110, and 67 belong to SMTP, POP3, and DHCP respectively.
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