This is, to my knowledge, the latest (and not previously generally
available) version of InterSLIP, which allows for both MacTCP and Open
Transport connectivity via a SLIP connection.
From the application's about page:
> ## InterSLIP (by InterCon)
>
> SLIP Connectivity for the Macintosh
> InterSLIP is provided free of charge to the
> members of the Internet community.
> Technical support is available to registered
> users of TCP/Connect II and TCP/Toolz & Toyz
>
