6 ms·

You are obliged to pass on the TTL, you're not obliged to cache according to it. At least in my country (UK) I know of no law relating to DNS caching. Why thr

You are obliged to pass on the TTL, you're not obliged to cache according to it. At least in my country (UK) I know of no law relating to DNS caching. Why throwaway perfectly good data every few minutes that is only modified every couple of years, just so someone can move their domain quickly when they eventually wish to? It is my contention that a [caching] DNS service can do far better. Trusting user (domain owner) input blindly is not for me.

otterley 20d ago
It's not some sort of public law with public enforcement, but it is in the RFCs that govern the protocol. I should be a bit clearer here; the TTL is an upper bound on how long it can be cached. Caches are free to consult more frequently but not less frequently. That said, out of respect for upstream cache operators and authoritative servers, most DNS caches honor TTLs as best they can.
- inigyou 20d ago
  The IETF isn't the internet police. You don't have to follow its advice.
  - otterley 20d ago
    No, but if you didn’t, the internet wouldn’t really work all that well. It was the fact that participants, despite being independent, all agreed (either explicitly or implicitly) to adhere to the standards that it became a global network. If they hadn’t, the result would have been more of the same: independent networks that only had narrow interoperability at best. It’s a textbook example of how global cooperation can yield incredible results. Advocating to do things against agreed-upon standards without a compelling reason and without giving due consideration to the adverse consequences is one of the hallmarks of a bad engineer. Even Microsoft played nice with Internet standards for the most part (although with some notable exceptions at the application layer that got them well-deserved criticism).
    - inigyou 20d ago
      It was the fact that adhering to the standard was in the best interest of each participant. When it isn't, they don't.
      - otterley 20d ago
        It's impossible to know how often participants chose to stick to the standards anyway despite it not being in their best interest. Do you have any specific examples?
        inigyou 20d ago
        Linux routers responding ICMP from 192.0.0.8 when not having an IP address (currently being standardized). Clouds using class E address space (240.0.0.0-255.255.255.254). Routers that drop IP packets with options. The entire concept of NAT until the existing behavior was eventually standardized. Unnumbered interfaces.
        fc417fc802 19d ago
        I think all of those are examples of "[doing] things against agreed-upon standards [with] a compelling reason and [with] due consideration to the adverse consequences".
        inigyou 19d ago
        And the compelling reason is always profit.
        otterley 19d ago
        No it isn’t. Sometimes it’s security, or making the most out of limited resources. Besides, not all profitable ventures are bad.
        fc417fc802 18d ago

otterley 20d ago

It's not some sort of public law with public enforcement, but it is in the RFCs that govern the protocol. I should be a bit clearer here; the TTL is an upper bound on how long it can be cached. Caches are free to consult more frequently but not less frequently. That said, out of respect for upstream cache operators and authoritative servers, most DNS caches honor TTLs as best they can.

inigyou 20d ago
The IETF isn't the internet police. You don't have to follow its advice.
- otterley 20d ago
  No, but if you didn’t, the internet wouldn’t really work all that well. It was the fact that participants, despite being independent, all agreed (either explicitly or implicitly) to adhere to the standards that it became a global network. If they hadn’t, the result would have been more of the same: independent networks that only had narrow interoperability at best. It’s a textbook example of how global cooperation can yield incredible results. Advocating to do things against agreed-upon standards without a compelling reason and without giving due consideration to the adverse consequences is one of the hallmarks of a bad engineer. Even Microsoft played nice with Internet standards for the most part (although with some notable exceptions at the application layer that got them well-deserved criticism).
  - inigyou 20d ago
    It was the fact that adhering to the standard was in the best interest of each participant. When it isn't, they don't.
    - otterley 20d ago
      It's impossible to know how often participants chose to stick to the standards anyway despite it not being in their best interest. Do you have any specific examples?
      - inigyou 20d ago
        Linux routers responding ICMP from 192.0.0.8 when not having an IP address (currently being standardized). Clouds using class E address space (240.0.0.0-255.255.255.254). Routers that drop IP packets with options. The entire concept of NAT until the existing behavior was eventually standardized. Unnumbered interfaces.
        fc417fc802 19d ago
        I think all of those are examples of "[doing] things against agreed-upon standards [with] a compelling reason and [with] due consideration to the adverse consequences".
        inigyou 19d ago
        And the compelling reason is always profit.
        otterley 19d ago
        No it isn’t. Sometimes it’s security, or making the most out of limited resources. Besides, not all profitable ventures are bad.
        fc417fc802 18d ago