---
name: "i4bq921"
section: "4"
platform: "linux"
package: "freebsd-manpages"
version: "6.0-5"
release: "Debian 4.0 (Etch)"
platforms: ["linux"]
url: "https://new.carta.tech/i4bq921"
---

# i4bq921(4)

isdn4bsd pseudo device driver handling the Q.921 protocol

## NAME

**i4bq921** – isdn4bsd pseudo device driver handling the Q.921 protocol

## SYNOPSIS

**device** **"i4bq921"**

## DESCRIPTION

**i4bq921** is the ISDN D channel layer 2 handler.

## SEE ALSO

[i4bq931(4)](/i4bq931/4.md)

## STANDARDS

ITU Recommendation Q.920 and Q.921

## AUTHORS

The **i4bq921** driver and this manpage were written by Hellmuth Michaelis ⟨hm@FreeBSD.org⟩.