Sharing Ideas

Alice, a graduate student working on cryptography, attends a research conference talk by Bob, a former graduate student in her own department who is now a prominent researcher. By the end of the talk, Alice realizes that Bob's scheme is vulnerable to a cryptographic attack she has been developing for her dissertation. During the question/answer session, she raises her concerns. Bob admits that he had not considered an attack like the one Alice described.

Back home, Alice thinks further about Bob's scheme and comes up with a modification which repairs its weakness. She writes a short technical note describing her results.

Alice has observed that in her field, attacks on proposed cryptography schemes are frequently cleverer and more interesting than the attacked schemes themselves. Such attacks are often considered publishable results. So she sends her technical note to Bob with a cover letter proposing that either

1. Alice and Bob coauthor a journal paper based on his conference paper along with her attack and fix, or,
2. Alice proceeds alone to submit her technical note to the next conference.

Bob replies that he had already found a fix to his scheme similar to Alice's, and also had written a follow-up note of his own for the next conference. He does not think he should include Alice's name as a coauthor of his paper, since he has essentially done all the work. He offers no other suggestions for cooperation.

What, if anything, can and should Alice do?