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We consider Real-Time CORBA 1.2 (Dynamic Scheduling) distributable threads operating in multihop networks. When distributable threads are subject to time/utility function-time constraints, and timeliness optimality criteria such as maximizing accrued system-wide utility is desired, utility accrual real-time channels must be established. Such channels transport messages that are generated as distributable threads transcend nodes, in a way that maximizes system-wide, message-level utility. We present 1) a localized utility accrual channel establishment algorithm called Localized Decision for Utility accrual Channel Establishment (or LocDUCE) and 2) a distributed utility accrual channel establishment algorithm called Global Decision for Utility accrual Channel Establishment (or GloDUCE). Since the channel establishment problem is {\cal N}{\cal P}{\hbox{-}}{\rm complete}, LocDUCE and GloDUCE heuristically compute channels, with LocDUCE making decisions based on local information pertaining to the node and GloDUCE making global decisions. We simulate the performance of the algorithms and compare them with the Open Shortest Path First (OSPF) routing algorithm and the optimal algorithm. We also implement these algorithms in a prototype testbed and experimentally compare their performance with OSPF. Our simulation and experimental measurements reveal that GloDUCE and LocDUCE accrue significantly higher utility than OSPF and also perform close to the optimal for some cases. Furthermore, GloDUCE outperforms LocDUCE under high downstream traffic.
Real-time systems, multihop networks, real-time channels, time/utility functions.

K. Channakeshava, B. Ravindran and E. D. Jensen, "Utility Accrual Channel Establishment in Multihop Networks," in IEEE Transactions on Computers, vol. 55, no. , pp. 428-442, 2006.
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