I really love this draft and would like to see browser side implementation for the benefit of customers user experience. Today several services are implemented on top of DNS to filter malicious or unwanted traffic in an effective way, but customers cannot distinguish the blocking from a network error. This led to frustration or even worst put them in danger: a quick solution to the "network error" is to disable the protection and so be infected, or change browser. The server side implementation provides all the needed information to build a great user experience: in the example below I see at least 2 options
->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 24987 flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1 OPT PSEUDOSECTION: EDNS: version: 0, flags:; udp: 512 EDE: 17 (Filtered): ({ "c": [https://blocking.vodafone.com/blockpage?list=malwarecc], "s": 1,"j": "Malware C&C", "o": "Vodafone Internet Services" }) QUESTION SECTION: malw.scalone.eu. IN A Option 1 - better user experience, some complexity to avoid security risks if the contact URI is trusted it is possible to present in the GUI a real blocking page. The problem is that untrusted providers could use this method as an attack vector. Potential solutions could be: Browsers accept Exte4nded DNS Errors only from DoH servers. URI domain has to be covered by DoH server certificate. There could potentially be a vetting process e.g. through IANA, whereby filtering providers would need to register. Only registered and approved providers would then be permitted to use this method Option 2 - Sub-optimal user experience; however, a significant improvement over today's user experience. <Browser name> cannot open <filtered domain, not clickable> because it has been filtered by <name of the filtering service, "organization" field> Blocking reason: <blocking reason, " justification" field> Thank you Gianpaolo C2 General _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop