There are three NAT options within the Xbox One configuration. Each of these are specific to your particular router and network setup.
Open – Your network is behind a cone NAT. Moderate – Your network is behind a port-restricted NAT. Strict – Your network is behind a port-preserving port-symmetric NAT.
Offline System Update Diagnostic Tool on Xbox One: http://bit.ly/1e8bSs3 Network ports used by Xbox Live on Xbox One: http://bit.ly/1dCNLm0 xBox Support: http://bit.ly/1lE2QrK Xbox One operating system versions and system updates: http://bit.ly/1NiJS1j