HELP: TCP/IP for the ignorant?

["Dave Althoff, Jr." <dalloff@gcfn.org>]

Tonight I made a significant breakthrough.  Here's what I have:

Macintosh OS 10.2.3 <==> MacOS 7.5.3 <---> GS/OS 6.0.1
New G4                   Mac LC-III        Apple IIgs

I finally got the Ethernet card working in the LC-III, and it sits under 
the desk without keyboard, mouse, or monitor, happily running the 
Localtalk Bridge and behaving as a file server.  Ethernet connects it to 
the G4, PhoneNet cables connect it to the IIgs (soon to a second IIgs as 
well).

It all works.  Tonight I downloaded files on the G4, stored them on the 
LC-III and recovered them with the IIgs.  The IIgs can read files 
directly from the G4, but can't write to it even though it has the proper 
permissions, it generates a "parameter out of range" error.  But that's 
not such a big deal, after all, I've got that server in there.

Okay.  So now I can move files across the room without sending them 
across town first.  This is a dramatic improvement.  With some clever 
programming, I could probably do as someone described here recently, I 
could create a watch directory on the server, write files there with the 
IIgs and use those files to tell the G4 what I want it to do.

"But why should I stop there?" I thought.  I've learned recently that the 
MacIP link layer exists for Marinetti, though it might not be fully 
functional.  So I figured I'd download it and give it a try.  It would be 
just great if I could use the IIgs to telnet into my G4.  Particularly 
when Apple's not-quite-complete applications (culprits so far have been 
iTunes, iDVD, and DVD Player) decide to lock me out while using the whole 
screen.  Why have an iCrash when I could just log in remotely and iKill 
the iProcess?  (Oops, I guess I've been spending too much time with the 
Mac).  Besides, if I could log in to the Mac, I could do all kinds of 
neat things, with or without the Internet connection (which is another 
issue altogether).

Well, that's where I failed miserably.  My problem?  I have an isolated 
network here.  When I start Marinetti, one of the things it does...in 
fact one of the things it insists on...is to try and connect to an 
Internet gateway machine.  This is where I am getting lost.  My network 
consists of two computers connected to a hub, with one of those computers 
supplying the gateway to the LocalTalk network (which right now has only 
two machines on it).  That's the closest thing I have to a gateway on the 
entire network.  None of the machines on the network requires either a 
gateway or a DNS to function; I'm happy to refer to each machine by its 
IP address, and everything is in the same subnet.  Any suggestions for 
how to get Marinetti to allow this non-Internet connection to work?

(Any suggestions for how to allow the G4 to accept network connections 
via the Ethernet without accepting via the PPP adapter are also welcome, 
but that's not an Apple ][ issue...)

--Dave Althoff, ][.
    /-\        _       _          *** Thanks for a great season!! ***
   /XXX\      /X\     /X\_      _     /X\__      _     _        _____
  /XXXXX\    /XXX\   /XXXX\    /X\   /XXXXX\    /X\   /X\      /XXXXX
_/XXXXXXX\__/XXXXX\/XXXXXXXX\_/XXX\_/XXXXXXX\__/XXX\_/XXX\_/\_/XXXXXX