What is the tripartite analysis of knowledge? Is it succesful?

The tripartite analysis of knowledge suggests that there are three criteria which must be met in every case of knowledge, and that every time these three criteria are met one has a genuine case of knowledge. Taking x as any claim, the first criterion is that one has a belief in x. This is intuitive, after all, if you don't even believe it's raining, then of course you don't know that it is. The second criterion requires that x be true. Again, it seems obvious that if it isn't raining then you cannot know that it is. And finally the third criterion is that you are justified in believing that x. That is, you haven't just assumed that it's raining, but you've looked out the window and seen the rain, or you've heard it falling against the roof.All well and good so far. But in 1963 Gettier published a paper in which he gave an example of a man who had justified true belief, but who did not appear to have knowledge! One story goes something like this: suppose you walk into a room and glance at the clock. The clock says it's 13:30. And indeed, it is 13:30. So here you have a true belief (that it's 13:30) and you are justified in it (you looked at a clock, you didn't just guess). The twist is that the clock is broken! It broke yesterday at exactly 13:30 and you just happened to be lucky walking in at the right time! So it seems that you have met the tripartite analysis without having knowledge, and this implies that the analysis does not the criteria sufficient for knowing.