Issues on connection allocation for supporting distributed real-time systems on ATM networks

With the increase in use of distributed real-time systems (DRTS), the ability of networks to handle time-constrained traffic is becoming more and more important. This paper examines one of the most promising networks for future DRTS, namely ATM. On one hand, there exist applications with various types of time constraints associated with messages generated by control activities, database access activities, video-monitoring activities, etc., and on the other hand, two service categories, CBR and rt-VBR, have been defined by the ATM Forum to support real-time communications. We analyze some issues to be considered to provide ATM users with a formal approach to map timing constraints of messages onto ATM services. We also discuss the problem of globally allocating a set of ATM connections required by a distributed real-time application.