To Apple's knowledge, there is no AFP-compatible file service available for any IBM mainframe operating system. Someone could write one, using MacAPPC, but they would have to implement AFP on the mainframe end and create a custom application for the Macintosh. The Macintosh side would have to be written to "tunnel" or encapsulate AFP frames within SNA. One would have to examine their environment a bit closer to get a handle on what mainframe components would be required to accomplish this.
However, using APPC as a basis, a "simple" file server on the mainframe could be created which would allow the devices on the remote network to connect to it. This, however, would not be an AFP-compatible file server.
Something to investigate is a package called XCOM 6.2 from Legent Corp. (formerly Spectrum Concepts). XCOM, currently in development, sits on top of MacAPPC and permits file transfers to an IBM mainframe with a HyperCard front end. This package will support binary formats, allowing you to distribute Macintosh files from the mainframe, as well as text. Spectrum Concepts likes to position this as an RJE replacement package. This package, however, will not give you AFP/AppleShare look, feel, or functionality.
If there are 3X74 remote controllers installed, a 3270 file transfer package, like Avatar's, can provide a similar service in the 3270 world. A 3X74 replacement with similar capability is the Netway 1000. These packages allow MacBinary transfers, in addition to regular binary and text. These also do not have an AFP/AppleShare look and feel. DCA's MacIrma and Simware could also be used, but they provide binary and text transfers only, not MacBinary.
By using these packages in conjunction with a TSO-partitioned data set, one could create a "simple" file server, but without the ease of operation of AppleShare. Transport, in this instance, is file transfer. By transferring the files as text, one could share files with IBM PCs.
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