Slide 15 of 20
Notes:
Merge is needed in any system which allows users to share a resource. When a user alters a resource the server may be able to perform a merge automatically or the user may want to request that the server perform a merge for them. The server must be able to ask the user to perform a merge in cases when the server can not. In addition if the server knows that it will not be able to perform a merge on a particular file it should inform the user at an appropriate time, such as Check Out.
It would seem that a combination of a new header and appropriate error messages will satisfy all of these requirements.