If Smalltalk is pretending to be Unix, it could just speak NFS I suppose. Or use HTTP. Or 9P. Certainly there are classes in most images that model file systems

If Smalltalk is pretending to be Unix, it could just speak NFS I suppose. Or use HTTP. Or 9P. Certainly there are classes in most images that model file systems. But thinking of Smalltalk as its own thing, and coming at the angle of interoperation between systems across networks at a higher level than chunks of untyped binary data, there are a few contenders: there have been various distributed Actor implementations. CORBA was available, back when that was relevant. Craig Latta has been doing some wonderful crazy things with interoperation between separate images (e.g. Context, nee Spoon: http://netjam.org/context/ http://netjam.org/context/).