---
name: "rlm_idn"
section: "5"
platform: "linux"
package: "freeradius"
version: "3.2.10-4"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/rlm_idn"
---

# rlm\_idn(5)

FreeRADIUS Module

## NAME

rlm\_idn - FreeRADIUS Module

## DESCRIPTION

When instantiated, the *rlm\_idn* module provides an xlat for performing IDNA encoding of internationalized domain names. Decoding and other similar encodings like plain punycode are not currently supported.

For example, the following unlang expression would evaluate to TRUE:

"%{idn:fūbar.site}" == "xn--fbar-v7a.site"

Each instance of rlm\_idn may take the following parameters:

- use\_std3\_ascii\_rules

  This boolean is set by default and prohibits e.g. underscores in domain names.

- allow\_unassigned

  This boolean is unset by default, which prohibits use of unassigned Unicode points.

## FILES

*/etc/raddb/radiusd.conf*

## REFERENCES

RFC 3490

## SEE ALSO

[**radiusd**(8)](/radiusd/8.md), [**radiusd.conf**(5)](/radiusd.conf/5.md) [**idna\_to\_ascii\_8z**(3)](/idna_to_ascii_8z/3.md)

## AUTHOR

Brian S. Julin, bjulin@clarku.edu