An implementation of F-channels

Units of Computation in Fault-Tolerant Distributed Systems

“…Thus a forward flush message provides a message reception ordering that is weaker than the FIFO ordering. Many implementations of F-channels and so the primitive for sending an f are possible; one of these implementations is given and others are referred to in [2]. An f-marker is an f that is used as a marker in this algorithm.…”

Integrated Network Barriers

“…The simplest form of an integrated barrier is based on Ahuja's Flush primitives [2], [3]. Ahuja creates a separate flush packet for each source/destination pair hs; di, and the network ensures the following semantics: all packets from s to d are ordered with respect to the flush packet.…”

“…3 However, the original barrier formulation by Harry Jordan was for a message passing architecture [17]. Barriers are an important coordination mechanism, and several commercial architectures provided hardware implementations including the CM-5 [19] and the T3D [21].…”

An implementation of F-Channels for possibly cyclic networks

“…Whenever no confusion can arise we refer to "an f or a t" as "mft", "an o or a 6" as "an ob". Various implementations of an F-Channel on top of a non-FIFO channel are presented in the literature [3,2,6,71. They can be classified as end-to-end implementations [2,6,7] and node-to-node implementation [3].…”

“…Various implementations of an F-Channel on top of a non-FIFO channel are presented in the literature [3,2,6,71. They can be classified as end-to-end implementations [2,6,7] and node-to-node implementation [3]. Compared to the end-toend implementations, the node-to-node implementation of [3] uses selective flooding [81 in which message overtaking is strictly controlled at each switch node such that illegal overtaking is inhibited.…”