yep on a fitz!box 7590 how do I stealth this port
Well officially via AVM ‘No’ – but have a read of this thread as some have tried this option with success, make sure you test all your ports afterwards just to make sure ?
Stealthing port 113 on NAT routers
https://www.grc.com/port_113.htm
———
In Brief:
In theory to configure a NAT routers to full stealth. The trick is to use the router’s own
“port forwarding” configuration options to forward just port 113 into Very high ip address.
i.e.
Set the router to forward port 113 packets to a completely non-existent IP address, one way up at the end of your router’s internal address range. The router will then NOT return a port closed status. It will simply forward the port 113 packet “nowhere” . . . and your network will be returned to full stealth (in theory)
Never tried this but does sound feasible. 
In a completely sane world, madness is the only freedom (J.G.Ballard).
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