an ISDN based PBX for Linux

Formerly known as "PBX4Linux", Linux-Call-Router is not only a router, it is a real ISDN PBX which interconnects ISDN telephones and ISDN lines. It is possible to connect telephones to a Linux box. It is a pure software solution except for the ISDN cards and telephones. The great benefit is the NT-mode that allows to connect telephones to an ISDN card. Special cards are needed and a little bit of different cabeling. It supports lots of features, that only expensive PBXs have. It include a channel driver that can link LCR to Asterisk PBX.

LCR is open source and under GPL.

View the list of features and read the HOWTO for a quick start.
Check the list of most cards that are capable of connecting telephones to it.

LCR can run a GSM network in conjunction with OpenBSC. Refer to the page for more information on running your own GSM network. A howto will follow.
For changes check README file inside the source tar.

To be able to run LCR you will need:

HFC multiport cards / HFC-E1 cards

Get additional tone/announcement sets: (only for fun)

For using the Bluebox with Linux-Call-Router, check this out.

For more info, write to For LCR and mISDN questions refer to the mailing list of the isdn4linux project:

Visit the download area for latest release.