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I've been reading about universal hashing, but I'm confused by all these different terms and notations. Could someone help me understand the precise meaning or relation between the following terms:

  • universal hash family
  • pairwise independent hash functions
  • 2-universal hash family
  • strongly universal hash family
  • delta-universal hash family
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We're not here to do your homework. – orlp Sep 16 '13 at 9:29
Really got confused by looking at the terms with different explanations and notations in different papers and books. unhappy with the treatment got by posting it here. probably this is my last question. let me do my homework. – Govinda R Y Sep 16 '13 at 10:45
With all due respect, your question shows no research effort whatsoever and looks like it's almost a verbatim copy from an assignment. On top of that there are multiple seperate questions there that should be a standalone question. On stackexchange we strive to be useful to future visitors by building up a knowledge base, and the question in your current form is unlikely to be as useful and clear for future visitors as it would be if you asked seperate questions. That's the reason why I downvoted and said we're not here to do your homework - there's no need to feel insulted. – orlp Sep 16 '13 at 10:58
@nightcracker: Actually, I think there's a reasonable question in here. All these terms are closely related to universal hashing, and explaining the precise differences between them would be useful. I've tried to edit the question to make it less "homeworky" (@Govinda: please check my edits and fix anything you don't like), and may try to answer it later when I'm not so busy. – Ilmari Karonen Sep 16 '13 at 11:57
llmari Karonen: Really delighted with your response sir. Waiting for your valuable answer. Meanwhile, I will continue doing my 'homework'. – Govinda R Y Sep 17 '13 at 5:15

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