# NAT Traversal `lnd` has support for NAT traversal using a number of different techniques. At the time of writing this documentation, UPnP and NAT-PMP are supported. NAT traversal can be enabled through `lnd`'s `--nat` flag. ``` ⛰ lnd ... --nat ``` On startup, `lnd` will try the different techniques until one is found that's supported by your hardware. The underlying dependencies used for these techniques rely on using system-specific binaries in order to detect your gateway device's address. This is needed because we need to be able to reach the gateway device to determine if it supports the specific NAT traversal technique currently being tried. Because of this, due to uncommon setups, it is possible that these binaries are not found in your system. If this is case, `lnd` will exit stating such error. As a bonus, `lnd` spawns a background thread that automatically detects IP address changes and propagates the new address update to the rest of the network. This is especially beneficial for users who were provided dynamic IP addresses from their internet service provider. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.lightning.engineering/lightning-network-tools/lnd/nat_traversal.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.