In this example the network consists of a client and a server.
IP addresses and routing tables are set up by IPv4NetworkConfigurator.
The ber (bit error rate) of the channel between client and server
depends on the selected configuration.
The client sends 100 MB of data to the server using TCP.
Connections throughput is measured by a throughput meter.
Different configurations demonstrate the impact of TCP's optional selective
acknowledgment (SACK) option on connections throughput.