[rescue] FDDI <-> ethernet

[Paul Sladen]

On Thu, 27 Sep 2001, Brian Hechinger wrote:

> > what you REALLY want is for it to act like a bridge.  So that it 
> > translates the packets directly without altering them.  I don't know 

Presumabley:

  PPP [ISDN] n.1/29 ---- [Bridge] ----- n.2/29 - n.6/29

Where the bridge also happends to have an IP.  Having thought about it;  
gut feeling that the following would be better:

  PPP [ISDN] 10.0.0.1/30 -- 10.0.0.2/30 [Ultra5] static.1/29 {{}} static.6/29

ISDN uses 10.0.0.2/30 as default route;  Everyone else uses U5 as default
route, everything works and everyone is happy!  (except traceroute fans).

> anyway, the reason i'm even posting is: does linux properly do MTU translations?

Hum, aren't we talking /bridging/ here?  Isn't this what Higher-level
MTU-Discovery is all about?  {AFAIK} ``Bridgeing'' between different MTUs,
requires an understanding of layer 3?

So you could do it;  but the world kluge comes to mind, and it would be
Brouting (transparent routing).  Personally think this is sickly.

Surely all you need to do is to get the Sun box to proxy arp for the ISDN
modem, and vis-versa in the other direction;  Hum, you'd have to tell or
your FDDI to use 1500mtu though for traffic going to the ISDN port, I don't
know whether you could get this to work on everything?

> bridging under solaris.  hmmm.

Re, the other person, blindingly easy under Linux... but well Solaris has to
be crap at some things. ;-)

Paul

e&oe.
PS.  FDDI does /rock/.... pity the ethernet MTU sucks so much ;-)