February 3, 1998 ISDN 4

### NAME

isdn - ISDN kernel to userland master device

### SYNOPSIS

pseudo-device isdn

### DESCRIPTION

The isdn device driver is used by the isdnd(8) daemon to exchange messages with the ISDN kernel part for the purpose of call establishment, control and disconnection and to access various control and status informations.

The messages and message parameters are documented in the include file ```/usr/include/netisdn/i4b_ioctl.h`.

The available ioctl's are:

I4B_CDID_REQ
  Request a unique Call Description IDentifier (cdid) which identifies uniquely a single interaction of the local D channel with the exchange.
I4B_CONNECT_REQ
  Actively request a call setup to a remote ISDN subscriber.
I4B_CONNECT_RESP
  Respond to an incoming call, either accept, reject or ignore it.
I4B_DISCONNECT_REQ
  Actively terminate a connection.
I4B_CTRL_INFO_REQ
  Request information about an installed ISDN controller card.
I4B_DIALOUT_RESP
  Give information about call setup to driver who requested dialing out.
I4B_TIMEOUT_UPD
  Update the kernels timeout value(s) in case of dynamically calculated shorthold mode timing changes.
I4B_UPDOWN_IND
  Inform the kernel userland drivers about interface soft up/down status changes.
I4B_CTRL_DOWNLOAD
  Download firmware to active card(s).
I4B_ACTIVE_DIAGNOSTIC
  Return diagnostic information from active cards.

Status and event messages available from the kernel are:

MSG_CONNECT_IND
  An incoming call from a remote ISDN user is indicated.
MSG_CONNECT_ACTIVE_IND
  After an incoming call has been accepted locally or an outgoing call has been accepted by a remote, the exchange signaled an active connection and the corresponding B-channel is switched through.
MSG_DISCONNECT_IND
  A call was terminated.
MSG_DIALOUT_IND
  A userland interface driver requests the daemon to dial out (typically a network interface when a packet arrives in its send queue).
MSG_IDLE_TIMEOUT_IND
  A call was terminated by the isdn4bsd kernel driver because a B-channel idle timeout occurred.
MSG_ACCT_IND
  Accounting information from a network driver.
MSG_CHARGING_IND
  Charging information from the kernel.

### SEE ALSO

isdnd(8)

### AUTHORS

The isdn device driver and this man page were written by Hellmuth Michaelis <hm@kts.org>
.