![cisco ios port forwarding cisco ios port forwarding](https://www.cisco.com/c/dam/en/us/support/docs/smb/routers/cisco-rv-series-small-business-routers/images/cole-032415-sec1step1.png)
![cisco ios port forwarding cisco ios port forwarding](https://ber10thal.com/blog/wp-content/uploads/2015/02/one-to-one-nat.png)
If present it should be implemented without NAT (NAT is wholly unnecessary with IPv6 and only adds complexity) and with a stateful firewall that permits bidirectional UDP conversations. IPv6 is recommended and can greatly improve direct connection reliability if supported on both ends of a direct link.Supporting either UPnP or NAT-PMP on your network can greatly improve performance by allowing ZeroTier endpoints to map external ports and avoid NAT traversal entirely.These guidelines are consistent with the vast majority of typical deployments using commodity gateways and access points. Recommended Local Network and Internet Gateway Configuration Make sure all of your nodes are updated to the latest release. Other settings such as "local isolation" can also interfere significantly with performance by forcing local traffic to traverse the Internet. If your network configuration is hostile to peer to peer network connectivity, most of your ZeroTier traffic will end up being relayed indirectly.
![cisco ios port forwarding cisco ios port forwarding](https://www.cisco.com/c/dam/en/us/support/docs/smb/routers/cisco-rv-series-small-business-routers/images/tz-05092108-nat-rv34x.png)
But "some level of connectivity" does not mean "optimal connectivity." This page details the physical network configuration that we recommend for best results. We provide multiple layers of fallback so that some level of connectivity can be achieved through even the most restrictive or broken physical networks. ZeroTier is designed to work in as many environments as possible.