NAME

isdns − IP address file for ISDN/X.25 interface

DESCRIPTION

The /etc/isdns file contains the mapping between Internet addresses and the corresponding ISDN or PSPDN addresses, one mapping per line.  For hosts connected via the is(4) circuit mode ISDN interface the contents should be:

Interface address as specified in hosts(5).
ISDN address following E.164.
ISDN subaddress (optional).

Subaddressing is not supported on all ISDNs. 

For hosts connected via virtual circuits on the dx(4) packet mode interface the contents should be:

Interface address as specified in hosts(5).
PSPDN address (X.121)  or ISDN address (E.164).
PSPDN extended address or ISDN subaddress (optional).

The items are separated by white space (blanks, tabs).  Use hyphens “−” in addresses to improve readability.  A “#” indicates the beginning of a comment; characters up to the end of the line are not interpreted by isdnset(8).

On some networks the representation of addresses differs in incoming and outgoing calls (say, presense of area code or escape characters).  In this case multiple lines should be used for each host.  Outgoing calls always use the first entry, whereas incoming calls are accepted if matching any one of the entries.  A single hyphen “−” matches the absense of an address; this may, however, foul IP routing and compromise security. 

If you are connected to a PSPDN (using X.25) and the remote host uses packet mode on an ISDN, the remote host usually does not have an X.121 address.  In this case, the address to specify in isdns typically consists of the international ISDN address (E.164, including country code) prefixed by an escape code (X.122 recommends “0”), with the remote subaddress (if any) going as extended address. 

Conversely, if you use the Packet Handler of your ISDN to call a remote host on a PSPDN, a “0” commonly is required as prefix to the full PSPDN address (X.121, with Data Network Identication Code). 

The sample /etc/isdns below could be for a host on a Packet Switched Network(PSPDN and ISDN Packet).  All X.25 interfaces must be on the same IP network. 

      packet1262459876543# PSPDN -> PSPDN
      packet24401-1234567
      packet34408-9012345
      packet41-0-81-3-5123-45674711# PSPDN -> ISDN
      packet51-4401-1234567# ISDN -> PSPDN

After updating /etc/isdns run isdnset(8) to make the changes effective.

FILE

/etc/isdns

SEE ALSO

isdnset(8), isdn.conf(5), isdnload(8), inet(4F), ifconfig(8C)

NEWS-OSRelease 4.1C