2.
If
you
are
planning
to
register
remote
extensions,
you
have
to
port
forward
5060(UDP+TCP),
10001
‐
10500(UDP)
on
your
router/firewall.
And
NAT
support
should
be
enabled
on
Advanced
‐
>
Options
‐
>SIP
Settings
page.
Both
“
External
IP
”
and
“
External
Host
”
should
be
your
public
IP
address,
or
can
be
your
DDNS
domain.