DNS over HTTPS (DoH) was introduced to prevent attackers from monitoring your browsing habits or re-directing you to malicious websites simply by snooping DNS traffic. DoH pairs DNS queries with the encryption power of HTTPS instead of communicating in plain text. Traditional DNS lookups are performed unencrypted over port 53, but DoH lookups occur inside HTTPS traffic over port 443.
Cisco Umbrella provides DNS over HTTPS to keep DNS queries private by using DNS over HTTPS (DoH) in supporting web browsers such as firefox or chrome. The browser DNS traffic becomes encrypted to ensure confidentiality on Internet. Umbrella the following IP addresses for DNS over HTTPS:
doh.umbrella.com -> 208.67.222.222 and 208.67.220.220.
Enable DNS over HTTPS. Under Use Provider field, select Custom and enter the following URL https://doh.umbrella.com/dns-query.