The

User's Manual

Release 0.8.0, (C) 1999

Thorsten Westheider
Carsten Pfeiffer
Christian Demmer
Christian Zander

Overview

1. What is kISDN?

2. Requirements


The configuration utility kcmkisdn

3. What does kcmkisdn do?

4. What does kcmkisdn not do?

5. Account configuration

5.1 ISP settings (Provider)

5.2 IP settings

5.3 Nameserver settings (DNS)

5.4 Authentication

5.5 Giving access to users

5.6 Callback

5.7 Other settings

6. General configuration

7. HiSax configuration

8. Problems and solutions


The dialer kisdn

9. What does kisdn do?

10. What does kisdn not do?

11. Dialing up a provider

12. Dial on demand

13. Channel bundling

14. kISDN's display

15. Individual settings/registration


The kisdn telephone

16. Preparations

17. Starting it up

18. The first call

19. The different telephone controls

20. Treatment of incoming calls


Appendix

A. Preparations

B. Supported Hardware

C. Configuration of ISA-Plug&Play cards

D. How to configure the kernel correctly

1. What is kISDN ?

kISDN is an isdn4linux frontend (I4L - the linux ISDN utility package) with three major aims:
  1. The configuration process is to be short and simple, no matter if you are a linux novice or an experienced "hacker".
  2. The ISDN line activity is to be monitored optimally.
    (ISDN, in contrast to analog modems, does not produce noise, neither are there flashing LEDs; connections are established within seconds)
  3. ISDN services, which are not normally available through Perl scripts etc. (e.g. a telephone) are to be made available through kISDN, without overwhelming the user with technical details; a graphical user interface (GUI) takes care of that.

Ideally kISDN is to free the user from any internal I4L configuration details. That especially applies to the configuration of the PPP daemon ipppd and to the one of the ISDN interfaces, with which the Linux kernel communicates with the rest of the world. Usually very little information about the ISDN adapter card (manufacturer, resources) and the access provider ( Internet service provider, ISP ) is needed to connect to the internet using kISDN.
Starting with version 0.6.0 kISDN consists of two separate programs. On the one hand there is kcmkisdn, responsible for the hardware and ISP configuration. It must be run with root priviledges (either directly or SUID). kcmkisdn is also used to give access to users, who may then connect to the ISP using the dialer kisdn.
Starting with version 0.7.0 kISDN offers ISDN telephony - that is calls can be made or accepted; in the latter case, a small dialog pops up asking you whether or not you wish to accept the incoming call. There are some incompatibilities with the Linux kernel sound driver (OSS/Lite), however as it can not transfer audio data in two directions at the same time (and is thus not capable of fullduplex operation). There are currently two alternatives:

  • Commercial OSS drivers, available at http://www.4front-tech.com, at the cost of $20
  • The ALSA driver (Advanced Linux Sound Architecture), which is currently under development. Since it is published under the terms of the GNU public license (GPL), you can get your copy free at http://alsa.jcu.cz

We tested kISDN with both drivers and found them to be working flawlessly; there is the possibility, however, of the ALSA driver not yet supporting your soundcard; with a Soundblaster 16 (and all cards based on it, SB AWE32 and SB AWE64) you won't have any trouble.
Theoretically, all ISDN cards supported by the HiSax driver are also supported by kISDN. In case that a future version of I4L supports a particular card, but kISDN does not, simply send us a short notification; we will release a patch and see to it that all future versions of kISDN will support the card in question. Please check the list of supported cards.


2. System requirements

kISDN was developed for the K Desktop Environment (KDE) under Linux and relies on both the Qt and KDE libraries. You can get Qt at http://www.troll.no and KDE at http://www.kde.org (free of charge). If you decide to compile the kISDN package yourself, you will need the Qt and KDE developer's kits, since they contain definitions needed by the compiler. Naturally you will need a C++ compiler, a simple C compiler won't suffice. For those who do not wish to compile kISDN themselves, we try to make RPM packages available as soon as possible; when in doubt, the source code ( tar.gz format ) is typically the latest.
As kcmkisdn takes care of the configuration, it requires root privileges. Under Linux or Unix in general, this is a controversial topic. There are two ways to master the configuration.

  • give kcmkisdn root permissions with chmod u+s kcmkisdn . This is not the recommended method. It allows each and every user to reconfigure hardware and ISP settings. On a system, where root and user are the same person this solution might be acceptable, in all other cases, however, we recommend using the second method
  • run kcmkisdn as root and give access to kisdn only to selected users. This is the recommended method, since it does not require a program to run suid root which usually compromises security

The dialer kisdn requires root privileges. Setting a program suid root is subject to highly controversial discussions, as mentioned before, but there are some reasons why it cannot be avoided here: kisdn must insert kernel modules (e.g. HiSax), it must configure the ISDN adapter as what is called a device, and for Dial-on-Demand it must also redirect the kernel IP routes. For all these changes root permissions are essential, unless other programs are set suid root. Since the account configuration also contains the passwords (logically), the configuration files - the ones used by kISDN and also the ones used by ISDN4Linux - would have to be readable at least by user groups, and not only by root. kISDN creates a configuration file in each user's home directory which contains every piece of information concerning the account, including username and password. To avoid most security leaks, this file is created readable and writable only by root, to make it and all other kISDN configuration files accessible to as few users as possible (only root). The division of kISDN into kcmkisdn and kisdn assures that the chosen users can dial up the ISP with kisdn (running suid root) but will not be able to reconfigure accounts, since that requires kcmkisdn which should be available only to root (and not be running suid root).

If you configured one or more accounts using kcmkisdn and the HiSax driver is to be loaded as well, it is recommended that you test your configuration with kisdn. In case of errors, they can be corrected only with kcmkisdn. A kisdn user will have no other option but to wait for the system administrator to rework the configuration with kcmkisdn.

Back to the overview


T. Westheider, Ch. Demmer, Ch. Zander / January 8 1999 - kISDN Release 0.8.0