I am currently doing some study on differential cryptanalysis.
However, I have two open questions in the field.
The first question is: How can I calculate the number of messages necessary for a successful attack?
I have read that if you have found a concrete characteristic by the cipher with probability $p$ that the number depends directly on $p$, which is understandable. However, I don't know how to calculate the number and more importantly, I can't find any literature (book or paper). If someone has a concrete tip, I would like to read it.
My second question is: Is there a measure for evaluating a probability $p$ of a characteristic? How high (or good) should a probability be for the attack to be successful? Are there any literature recommendations here?