CompTIA Network+ Practice Test

Which of the following is a characteristic of DNS over HTTPS (DoH)?

1. Uses port 853 for transmission

2. Looks like regular web traffic over TCP port 443

3. Transmits in plaintext by default

4. Is not supported by major browsers

The correct answer is: Looks like regular web traffic over TCP port 443

DNS over HTTPS (DoH) is designed to enhance privacy and security by allowing DNS queries to be sent over HTTPS, which is the same protocol used for secure web traffic. One of the key characteristics of DoH is that it appears similar to standard web traffic because it operates over TCP port 443. This feature helps to camouflage DNS requests as ordinary web browsing activity, which complicates attempts at censorship and traffic analysis by third parties. The architecture of DoH leverages encryption, providing confidentiality for DNS queries which helps prevent eavesdropping and manipulation of DNS traffic. Since it functions over the same port as secure HTTP connections, it makes it more challenging for potential adversaries to identify DNS requests in the network and apply filters. While port 853 is traditionally used for DNS over TLS (DoT), DoH does not use this port. Instead, the encryption is built on HTTP/2 or HTTP/3 protocols and operates on port 443. Additionally, DoH does not transmit information in plaintext; rather, it employs encryption to secure the data being transmitted. Lastly, DoH is widely supported by major web browsers, contrary to the claim in one of the options. This is significant as it indicates that the adoption of DoH is