Status of "Synchronization Domain" technology

Why do I find discussion of synchronization domains to be almost absent anywhere (books, articles, etc). Is it because it is considered an outmoded technique that is maintained merely for backward compatability? Or are its applications so rarified t开发者_如何转开发hat no one bothers with them?

I had heard of the SynchronizationAttribute before, which is integral to synch domains, but no one seems to discuss that attribute much either.

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Being placed in System.Runtime.Remoting it looks more like an implementation detail or a legacy COM technique. When you look at the namespace documentation this impression is reinforced because it talks about COM activation contexts. Most applications execute in a single process and never bother with remote execution of COM objects, so I guess for most people it's just not relevant.