Welcome to the Ubridge Page.

Deutsche Seite.

Ubridge makes the connection between the local Net (Intranet) and the Internet. The local PC´s do not have work with the ISDN connection, only the single UBridge PC does have the ISDN work. Through the definition of "port" denys your LAN can be protected (firewall concept). With an enhanced configuration your LAN can have active connections to different IP providers at the same time.
Ubridge is a ethernet bridge for TCP/IP. It was developed to connect machines, running linux, win or other machines, to the internet via ISDN. Today Ubridge can connect a range of IP addresses to the internet. It works just like a Router, but without an IP address for itself. Up to 4 ethernet interfaces at the same time are supported.

Main features are:

  • can do IP NAT.
  • can do IP Masquerading (without ICMP).
  • do caching of IP packets.
  • can do logfile view with HTTP.
  • can be used as IP-Monitor for TCP, UDP and ICMP.
Ubridge with internet and intranet
ISDN TCP/IP Connectivity can be activated with Ubridge:

What do you need to run Ubridge
  • PC286 or better with 640Kbyte RAM for the bridging operation.
  • ISDN card(s) with packet driver ( tested with ispa ).
  • ETHERNET card(s) and a packet driver. (tested with ne2000 and 3c509)


Download Ubridge version 0.99g ~ 120 Kbyte.

Here is a early update Ubridge 1.01 only the EXE ~ 55 Kbyte.

Do your own recycling project:

Use your "old" PC.
It will be used more energie in the construction of a PC as in the living time of a PC. I have not invest my money in a new PC or router.
The use of a monitor and a keyboard is not required in the use of ubridge. If you have an old PC it is a good choice to use the old network and isdn cards.


You can drop me a e-mail.

©1996 ... 99 Bernhard Rath.