In Computer Science Helman-Bader-JaJa model is a concise message passing model of parallel computation defined with the following parameters:
p is number of processors. n is the problem size. m is number of machine words in a packet sent over the network. τ is the latency, or time at which a processor takes to initiate a communication on a network. σ is the bandwidth, or time per machine word at which a processor can inject or receive m machine words from the network. T c o m p is the largest computation time expended on a processor. T c o m m is the time spent in communication on the network.This model assumes that for any subset of q processors, a block permutation among the q processors takes ( τ + σ m ) time, where m is the size of the largest block.
