Well I answered my own question as it happens.

At 8:23 PM 7/22/96, Michael L. Kornegay wrote:
>In Regards to your letter <v02140b02ae19a91a226b@[137.79.51.141]>:
>> Does anyone know if it is possible to use a unix PPP server (such as
>> MacBSD, although I really want to use a Solaris 2.5 machine) to provide
>> AppleTalk Remote Access between two MacOS machines running MacPPP?
>>
>> I believe I can do AppleShare using Netatalk.  Just want to know if
>>that's all.
>
>PPP consists of a link control protocol (LCP) and ? protocols (like IPCP,
>IPX control protocol, and AppleTalk control protocol, ...).  I doubt that
>NetBSD's PPP implements the other (other than the IP control protocol)
>component protocols needed for AppleTalk PPP.  I dont know if the netatalk
>package comes with any code to add such capability to a ppp implementation.
>
>Also, as far as i know, Apple has not yet to delivered a PPP version of ARA.
>
Well my new issue of MacUser arrived in the mail the same day I posted the
original question.  In the MacWeek report they detail Apple's development
plans for supporting ARA over OT/PPP in about a year.  They will also be
adding some Unix protocol support (NFS or FTP, I forget) to AppleShare.
ARA and these other improvements will be bundled with some version of
System 8.

The comments for Netatalk lead me to think that it may support routing ARA
packets through a U*ix box.  It does all the right low-level stuff, and it
shouldn't have to worry about the higher level stuff.  I guess that means
you could do it if you were running Netatalk on both ends of the PPP
connection.  The problem is that the ARA code on either end only talks
AppleTalk.  MacTCP and OT support encapsulating IP packets on an AppleTalk
network, but there is no support for doing things the other way around,
yet.

I do look forward to running AppleTalk over PPP.  Best of both worlds.

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