ddrs-lab2/code/circnets/prodbound.R

# Determines the flow blocking probabilities of a circuit switched network using
# the product bound.

source("code/circnets/erlB.R")

##############################################################################
# Insert here the input parameters

# Links must be identified by contiguous integers starting at 1. These numbers
# must be used as indexes of the LinkCapacities vector and of the vectors
# defining the routes of each flow. Do not use the node numbers for this
# purpose!

# Define here the capacity of each link. The capacity must be expressed in number
# of circuits. This assumes that each call occupies one circuit.
LinkCapacities <- c(0, 5, 5, 0, 5)

# Define here the flows. Flows is a list of lists that stores in each list (1)
# the offered load and (2) the route of each flow; the routes must be defined
# using the link identifiers (and not the node identifiers)
Flows <- list(
  list(load = 0.5, route = c(2, 5, 3)),
  list(load = 0.5, route = c(3)),
  list(load = 0.5, route = c(2, 5))
)

# Do not write bellow this line!
###############################################################################

numLinks <- length(LinkCapacities)
numFlows <- length(Flows)

# Computes load of each link
LinkLoads <- rep(0, numLinks)
for (j in 1:numFlows) {
  Route <- Flows[[j]]$route
  Load <- Flows[[j]]$load
  LinkLoads[Route] <- LinkLoads[Route] + Load
}

# Computes blocking probability of each link
LinkBlocking <- c(length = numLinks)
for (i in 1:numLinks) {
  LinkBlocking[i] <- erlB(LinkLoads[i], LinkCapacities[i])
}

# Computes blocking probability of each flow
FlowBlocking <- c(length = numFlows)
for (i in 1:numFlows) {
  Route <- Flows[[i]]$route
  AcceptProb <- 1
  for (j in 1:length(Route)) {
    Link <- Route[j]
    AcceptProb <- AcceptProb * (1 - LinkBlocking[Link])
  }
  FlowBlocking[i] <- 1 - AcceptProb
}

for (i in 1:numFlows) {
  cat(sprintf("Blocking probability of flow %d = %f", i, FlowBlocking[i]), "\n")
}