@techreport{TR-IC-99-21,
  number = {IC-99-21},
  author = {Delano M. Beder and Cecília Mary Fischer Rubira},
  title = {A Comparative Study of Fault-Tolerant Concurrent Mechanisms: {Atomic} Transactions, Conversations and Coordinated Atomic Actions},
  month = {September},
  year = {1999}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 17 pages.
    \par\selectlanguage{english}\textbf{Abstract}
      Distributed computing often gives rise to complex concurrent and
      interacting activities. In many cases, several concurrent
      activities may be working together, i.e., cooperating, to solve
      a given problem; in other cases the activities may be
      independent but sharing common system resources for which they
      should compete. In practice, different kinds of concurrency
      might coexist in a complex application which thus will require a
      general supporting mechanism for controlling and coordinating
      complex concurrent activities. Many difficulties and limitations
      occur when the object and action model is used to support
      cooperating activities. This paper discuss some of these
      difficulties and limitations and then presents an alternative
      model for constructing fault-tolerant distributed systems based
      on the concept of Coordinated Atomic (CA) actions which provides
      uniform support for both cooperative and competitive
      concurrency.
  }
}