IPv6 isn't SMTP

Owen DeLong owen at delong.com
Thu Mar 27 06:26:44 UTC 2014

On Mar 26, 2014, at 8:12 PM, Robert Drake <rdrake at direcpath.com> wrote:

> On 3/26/2014 10:16 PM, Franck Martin wrote:
>> and user at 2001:db8::1.25 with user at Who had the good idea to use : for IPv6 addresses while this is the separator for the port in IPv4? A few MTA are confused by it.
> At the network level the IPv6 address is just a big number.  No confusion there.  At the plaintext level the naked IPv6 address should be wrapped in square brackets.
> From:
> http://tools.ietf.org/html/rfc3986#section-3.2.2

Two errors, actually… As an RFC-821 address, it should be [email protected][IP]:port in both cases ([email protected][]:25 and [email protected][2001:db8::1]:25).


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