Jeff wrote (2020-10-22):

 JS>     Hello everybody!

 JS> I have seen questions and differing thoughts on the use of certain
 JS> nodelist flags and their preferred or correct usage. A couple such
 JS> flags are INA and IBN and how each should be used to specify nodelist
 JS> connectivity data. In looking through the current nodelist I see those
 JS> two flags used in a couple different ways.

 JS> Thoughts on which and why?

The I?? flags standard is unnecessarily complicated, because someone thought it
would be clever to invent different combination of the flags to save a few
bytes in the nodelist. But in the real nodelist people often waste 4 bytes with
the combination "INA:domain,IBN" (which could also be written as "IBN:domain").
The net result of this is additional complexity for the nodelist parser and the
user without any real world savings (which wouldn't matter anyway).

To keep it simple, just ignore the INA flag and use

IBN:domain
or
IBN:domain:port (if your mailer is listening on another port than 24554)

or
IBN:domain,IFC:domain,...
(as there are practically no ifcico-only or EMSI/telnet-only nodes and binkp is
the standard FTN TCP/IP protocol, IBN:domain[:port] is all we need).