SDB:How to Connect Ethernet Cards Via FireWire

From openSUSE

Version: 8.2

Situation

You want to set up an Ethernet connection via the FireWire port.

Procedure

The following modules must be loaded so that Ethernet can work via FireWire (ieee1394):

insmod ieee1394
insmod ohci1394
insmod raw1394

as well as the eth module:

insmod eth1394

After that, Ethernet is available via a Firewire interface that automatically receives the next higher device number. You can use "ip" to display all the Ethernet interfaces configured so far:

ip addr

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 50
    link/ether 00:48:54:13:79:44 brd ff:ff:ff:ff:ff:ff
    inet 10.2.107.134/24 brd 10.2.107.255 scope global eth0

The following commands:

ip addr add 192.168.11.11/24 brd + dev eth0
ip link set eth0 up

configures the interface with the values given above. The interface is then ready for use.

Restrictions:

Ethernet connections via FireWire only work so far among Linux PCs. In spite of being available for Windows, too, a different protocol is used, thus making it impossible to connect a Windows 2000 or XP machine to a Linux PC this way.

The reason: The Organization for Standardization provides for three (in fact almost four) transmission possibilities for IP via FireWire:

1. Direct IP via FireWire
2. Ethernet via FireWire without Ethernet encapsulation
3. Ethernet via FireWire with Ethernet encapsulation
4. Token-Ring via FireWire with Token-Ring encapsulation

The first approach only allows IP traffic via FireWire, excluding IPX, SNA, etc.

Approaches 2 and 3 allow everything Ethernet can do and differ from each other in the way data are transmitted through the FireWire bus. According to the second approach, data are wrapped in different FireWire packets depending on the Ethernet packet. In the third approach, data are first wrapped in an ordinary Ethernet packet and then transmitted via FireWire. For this purpose, a tunnel through FireWire is built for the Ethernet packets.

As far as we know, approach number 4 has not been implemented yet.

Windows 2000 and XP use approach number 2 to transmit Ethernet packets, whereas Linux uses approach number 3. The alternative driver "ip1394" (not included in SuSE Linux) uses approach number 1. Thus, it is currently not possible to connect a Windows 2000/XP PC with a Linux PC via FireWire.