Editing Open Transport (section)

===OT===
Open Transport was introduced in May 1995 with the [[Power Macintosh 9500|Power Mac 9500]]. It was included with [[System 7|System 7.5.2]], a release for the new [[Peripheral Component Interconnect|PCI]] based [[Power Mac]]s, and became available for older hardware later. MacTCP was not supported on PCI-based Macs, but older systems could switch between MacTCP and Open Transport using a [[Control panel (Mac OS)|Control Panel]] called Network Software Selector. Unlike MacTCP, Open Transport enabled users to save and switch between configuration sets.

[[Software developer|Developer]] opinion on Open Transport was divided. Some felt it offered enormous speed improvements over MacTCP. Some developers also liked it because it was flexible in the way it allowed [[Protocol (computing)|protocols]] to be "stacked" to apply filters and other such duties. However, the system was also large and complex. The flexibility of the Open Transport architecture, into which one could plug any desired protocol, was felt by some to be thoroughly overcomplicated. Additionally, most Unix code still used sockets, not STREAMS, and so MacTCP offered real advantages in terms of porting software to the Mac.

The vaunted flexibility of the Open Transport architecture was undermined and ultimately made obsolete by the rapid rise of TCP/IP networking during the mid-90s. The same is true in the wider Unix market; System V was undermined by the rapid rise of free Unix-like systems, notably [[Linux]]. As these systems grew in popularity, the vast majority of programmers ignored the closed STREAMS in favour of the BSD-licensed Sockets. Open Transport was abandoned during the move to [[macOS|OS X]], which, being derived from [[BSD]], had a networking stack based entirely on sockets.

Open Transport received [[deprecation]] status from in OS X 10.4 and its [[Software development kit|SDKs]]. Support was removed entirely from OS X in version 10.9 ([[OS X Mavericks|Mavericks]]).<ref>{{cite web|url=https://developer.apple.com/library/prerelease/mac/releasenotes/MacOSX/WhatsNewInOSX/WhatsNewInOSX.pdf|title=What's New in OS X 10.9 Mavericks|publisher=Apple Inc.|accessdate=2013-03-22}}</ref>