Re: The state of DNS support, was Deprecating SPF
Jay Daley <[email protected]>
| Newsgroups | gmane.ietf.dnsext |
|---|---|
| Message-ID | <[email protected]> |
On 26/08/2013, at 1:28 PM, Andrew Sullivan <[email protected]> wrote: > This isn't religion: I'm as sickend by > this use of TXT as anyone. But the world makes us as much as we make > the world, and I think the TXT fight _in this case_ is lost. Having thought about this for a few days I've changed my mind and I'm happy to see SPF(99) go. What clinched it for me was this note from Andrew above as it helped me realise my issue is with the misuse of TXT and not the solution of a new type specific to SPF. So let's let it go and I'm sure with a bit of thought we can find a way to fix the overloading of TXT and try to sell that as a better migration path for "v=spf1" in TXT than SPF(99) ever was. = We know the issues can be summarised as: 1. The key benefits people find from using TXT are - it is well supported - it is free form so any experimentation is possible and no standards body engagement is needed 2. The key issues with the use of TXT are - people not using prefixes and so conflating various uses (and as Hadriel points out, no prefix registry) - the wildcard issue, which I'm going to restate as how to define a policy at one level that applies to lower levels, is a key reason for not wanting to use prefixes. = So here's an example solution (and I mean an example since I'm sure there is a lot more to consider): 3. Create a new generic record for free form policy data that must be prefixed by protocol. For example: _spf .example.com. POL "a:mail.example.com -all" If we provide that one record then anyone can use it for any policy info without further need to change the DNS. To me that seems much more utilitarian than a protocol specific RR. = A solution for the wildcard issue is a bit more complex, but here's an example 4. Add an rdata field to the POL record that if set to "*" (asterisk) applies this policy to the next level _spf.example.com. POL * "a:mail.example.com -all" This record is then used to synthesise the POL record in exactly the same way that a wildcard is. 5. Or we could add a record under each sub-domain that refers back up a level: _spf.sub.example.com. POLPTR example.com. Jay -- Jay Daley Chief Executive .nz Registry Services (New Zealand Domain Name Registry Limited) desk: +64 4 931 6977 mobile: +64 21 678840 linkedin: www.linkedin.com/in/jaydaley _______________________________________________ dnsext mailing list [email protected] https://www.ietf.org/mailman/listinfo/dnsext