Initially I opened and forwarded every port Vonage recommended but have
pared it back to only 5060–5061 (UDP) and it seems to be working without a
hitch for the three + weeks that I've had it now, Comcast as the ISP. In my
outbound traffic shaping I've given the Vonage adapter high priority. I
haven't tried to saturate my upload to see if it helps or not. Peace of
mind I guess.