On Jul 30, 2017, at 8:55 AM, Randy Bush <randy@xxxxxxx> wrote:
To applications, a NAT64 IPv4 host just looks like an IPv6 host. The issues that come up tend to be either embedded IPv4 literals, or else cases where the app explicitly chooses which version of transport to use (e.g., OpenVPN used to do this). Also, if you open a tunnel and start resolving domain names through that, you will start getting IPv4 addresses, and all your IPv4 connections will transit the tunnel, which may not be what you want. I think there are also issues that come up with L2TP, but I don't know the details. The thing is, these issues are not random issues. They show up or they don't. They don't show up as flakiness: they show up as "it doesn't work at all." So knowing how many out of an un-selected population actually run into these issues is pretty interesting. That's why I want to make NAT64 the default. But I suppose I am trying to write a check the NOC would have to cash. |