For developers with a background in UNIX, a need for POSIX compliance, or a need to deploy an application across MacOS and UNIX systems, OpenTransport is a logical choice.
OpenTransport is also the preferred choice for a Mac-only application. It provides the highest performance of all network methods. The older MacTCP API's interface is being phased out, and Apple encourages all developers to move to the Open Transport XTI API.
The OpenTransport API's do not implement the higher layer internet protocols such as HTTP, FTP, gopher, etc. OpenTransport is, however, a building block with which these protocols are typically implemented.
If you wish to program to these higher protocols, Apple is developing a suite of internet access functions under the Cyberdog framework. Cyberdog is a component technology built on top of OpenDoc.
Although Apple does not provide one yet, there are a few internet access libraries being developed by various third parties.
For the CodeWarrior environment, there is a certain amount of network access available in the Powerplant framework.
Finally, for developers with a background in Microsoft Windows, or a need to
implement a cross-platform application, WinSock compatibility services are
provided through third party software available from NetManage (408 973-7171).
A good place to start is to investigate the following resources:
opentransport