some services, especially the free ones, requires you to send an "update" even if your IP is not changed.
If you do it too fast, it will be considered abuse.
If you do it too slow, your domain will expire.
These limits may vary for every service.
HFS has an embedded updater, so i need to comply to these limits.
It currently forces the update every 15 days.
DynDNS says after 30 days without an update your domain expires.
It states it is ok to update via their web panel every 25 days.
http://www.dyndns.com/support/kb/dyndns.html after "Inactivity Expirations"
They don't clearly say what should automatic updaters do, but i guess 25 can be a good value as well.
No-ip has a
max of 60 days. I didn't found a "min".
I hope 25 may be a good value for them as well.
If you find useful related information about these and other services, please report.
Unless something new is reported, next versions will use value "25 days".