Lab 9: Network emulation and statistics

The stats hook can be used to collect statistics about the co-simulation interface like:

• One way delay (OWD)
• Packet loss
• Packet reordering
• Sending rate

$ villas signal -r 1000 -l 10000 sine | villas hook -o verbose=true -o warmup=3000 stats

With network emulation

nodes = {
   udp_node1 = {
           type = "socket",
           layer = "udp",

           in = {
                   address = "*:12000"

                   signals = {
                           count = 8,
                           type = "float"
                   }
           },
           out = {
                   address = "127.0.0.1:12001",

                   netem = {
                           enabled   = true,
                           loss      = 0,      # in %
                           corrupt   = 0,      # in %
                           duplicate = 0,      # in %
                           delay     = 100000, # in uS
                           jitter    =   5000, # in uS
                           distribution = "normal"
                   }
           }
   }
}

In the first terminal:

$ villas signal -r 1000 sine | villas pipe etc/lab9_netem.conf udp_node1

In a second terminal:

$ villas pipe etc/lab9_netem.conf udp_node1 -x > delayed_data.dat

After a few seconds, press Ctrl-C to stop the processing. Now we can analyze the delay distribution of the received data:

$ villas hook -o verbose=true -o warmup=1000 stats < delayed_data.dat > /dev/null

For more details see Network Emulation

Go to [lab 10] =>(node-lab-10)