Research Proposal for PhD - Rude or Good I have completed my bachelors and am now nearing the end of my Master's, and I am looking for PhD positions across the globe in the field of Computer Science. While applying/perusing possible application paths for PhDs, I realized that while all universities recommend contacting a prospective advisor beforehand, none explicitly state whether or not I need to write a research proposal (some do enforce it during the application).

Now I am unable to decide if writing a research proposal (during the prospective supervisor search phase) is a good idea or if it is, well rude. 

My justification for each are:


Good: The prospective research guide gets to know the academic aspirations of the prospective students, analytic abilities etc.
Rude: He may not be interested in my area of choice at all and think of me as a know-it-all guy, who is not welcome to changes, analytic shortcomings etc.


What is the standard way of handling this dilemma (or is there an academia wide sweet spot on how to approach this)? Are there any major points that I am missing/should be aware of, in order to tackle this problem? 

Thanks.

Added Info: I do have a specialization and an area of interest and competence.
The first point to consider is whether you have a prospective research area in mind. Ideally at this stage you should have some specialisation, and a general idea of the field out would like to enter. If this is the case, it makes sense to write a proposal reflecting your interest. Don't make it too specific, but let it show that you have done your homework.

On the other hand, if you are unsure and open to exploring different fields, first select the groups you would like to join, see what work they do. Find a common area of interest and write a proposal based on that. This means you could potentially be writing many different proposals for different universities. The focus would be to ensure that the proposals are relevant to the audience in each case.

Either way, my opinion is that you should have a proposal ready. When you first contact the supervisor, you needn't attach the proposal, just convey your interest to work with him/her, mention some areas of interest and attach a CV.