I have two 1394 port in my computer, why did I get only one eth1394 interface?

I have two 1394 port in my computer, why did I get only one eth1394 interface?

[lepton]

Hi,
   My computer has two 1394 port, one is in the front panel, and another
is in the back. I found with linux 1394 ethernet support, I only get one
ethernet device named eth1.
   After read code, I found author says "This is where we add all of
our ethernet * devices. One for each host."
   Then my question is:
   1. Is it possible to use every 1394 port as a ethernet device?
   2. If not, which port should I plug my firewire line into?
   3. If I must plug my firewire line in some port, can I change the
default port to use?
   Thanks.

Re: I have two 1394 port in my computer, why did I get only one eth1394 interface?

[Stefan Richter]

(added Cc: linux1394-user)

lepton wrote:
>    My computer has two 1394 port, one is in the front panel, and another
> is in the back. I found with linux 1394 ethernet support, I only get one
> ethernet device named eth1.
>    After read code, I found author says "This is where we add all of
> our ethernet * devices. One for each host."
>    Then my question is:
>    1. Is it possible to use every 1394 port as a ethernet device?

Yes.

>    2. If not, which port should I plug my firewire line into?

Any one port.  Note though that front panel connectors may have a
slightly reduced signal quality due to the onboard pin headers, jumper
cable, and front panel board traces.

>    3. If I must plug my firewire line in some port, can I change the
> default port to use?

Not necessary.

To explain this further:  Each FireWire controller comes in two parts
(which are sometimes integrated on a single chip though):  The link
layer controller and the PHY(sical bus interface).  The PHY may have
several ports, but all of these ports belong to the same FireWire bus.
The PHY not only connect the link layer controller with each port, it
also acts as hub/repeater between those ports.

There are a few FireWire controller cards which come with two, three, or
even four link layer controllers on the same card.  These cards too have
one PHY per link layer controller, i.e. two/ three/ four PHYs on the
card.  These cards appear to the ieee1394 drivers like multiple cards
(and multiple FireWire buses), hence will give you multiple eth1394
network interfaces just like multiple separate cards will do.

So, you get as many eth1394 interfaces as there are link layer
controllers.  You can check the number of present link layer controllers
by lspci.
-- 
Stefan Richter
-=====-=-=== =--- -==-=
http://arcgraph.de/sr/

Re: I have two 1394 port in my computer, why did I get only one eth1394 interface?

[Jan Engelhardt]

On Aug 13 2007 17:24, Stefan Richter wrote:
>
>>    3. If I must plug my firewire line in some port, can I change the
>> default port to use?
>
>The PHY may have several ports, but all of these ports belong to the same
>FireWire bus. The PHY not only connect the link layer controller with each
>port, it also acts as hub/repeater between those ports.

So given one has two firewire ports with only one PHY, it is not possible
to make a firewall with two interfaces out of it, which each routed only to the
specific firewire port...


	Jan
-- 

Re: I have two 1394 port in my computer, why did I get only one eth1394 interface?

[Stefan Richter]

Jan Engelhardt wrote:
> On Aug 13 2007 17:24, Stefan Richter wrote:
>>The PHY may have several ports, but all of these ports belong to the same
>>FireWire bus. The PHY not only connect the link layer controller with each
>>port, it also acts as hub/repeater between those ports.
> 
> So given one has two firewire ports with only one PHY, it is not possible
> to make a firewall with two interfaces out of it, which each routed only to the
> specific firewire port...

Well, depends on whether one FireWire node could expose multiple network
interfaces on the same FireWire bus.  I'm not quite sure if the IPv4
over IEEE 1394 spec, RFC 2734, allows this.  It is however possible to
expose one RFC 2734 interface and one RFC 3146 interface (IPv6 over IEEE
1394) on the same bus --- hence it might also be possible to implement
more than one IPv4 interface per node per bus.  On a quick glance,
unicast doesn't seem to be a problem, but broadcast and multicast might be.

Linux' eth1394 driver implements only one IPv4 interface per bus, and no
IPv6 interface.

Anyway, an IP router from FireWire to FireWire seems to be a rather
exotic application, especially as LAN to internet router or firewall.
-- 
Stefan Richter
-=====-=-=== =--- -===-
http://arcgraph.de/sr/