Unattended Initiate (UI) and Round Robin (RR)



I need to learn about these two modem features/mechanisms but I can't
find anything in my available literature or by googling. I'm hoping
someone can explain these to me or give me a good site/ebook on both,
also if anyone knows where I can learn about Constant and Switched
Carriers I would be grateful :) Thanks alot in advance

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