ISP Requirements for OpenBSD

[Jim Michael <icypine45@yahoo.com>]

I am selecting a new ISP for a home dialup connection
and want to use OpenBSD for a firewall / NAT box.  

What requirements should I look for in an ISP to best
interface with OpenBSD?  I understand that some ISPs
are better suited for Windows-style than Unix-style
communications.  

Obviously I don't have a tech background.   I've been
studying / using OpenBSD for about a year and a half
and trying to learn as much as possible.  Changing ISP
is a significant change for me and I don't want to
depend on what I know.  I'd like to get an informed
opinion.  If someone could summarize the important
points for me I would greatly appreciate it.  Thank
you.
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