Page "AppleTalk" Paragraph 24

As the world quickly moved to IP for both LAN and WAN uses, Apple was faced with maintaining two increasingly outdated code bases on an ever-wider group of machines as well as the introduction of the PowerPC based machines.

This led to the OpenTransport efforts, which re-implemented both MacTCP and AppleTalk on an entirely new code base adapted from the standard STREAMS.

Early versions had problems and did not become stable for some time.

By that point, Apple was deep in their ultimately doomed Copland efforts.