Introduction to the mininet library in python

The Mininet library is a Python library for creating a virtual network experimental environment.It provides a simple and powerful interface that allows users to build, configure and manage the topological structure based on software -defined network (SDN). The MINET class library is very rich in function and can be used to develop, test and deploy various network applications and protocols.It provides an analog network environment that can create virtual switches, hosts and links by writing the Python code, and define the connection relationship between them.In this virtual network environment, you can easily simulate various network topology structures, from simple star topology to complex layered structures. The mininet library also provides some functions for testing and evaluating network performance.It can simulate network load and topology changes so that users can evaluate the performance of network applications under different conditions.In addition, MININET also supports running real network applications in the simulation environment for more real performance testing. The following is a simple example code that shows how to use the mininet library to create a basic network topology.In this topology, there is a switch and two hosts. python from mininet.net import Mininet from mininet.node import OVSSwitch, Host # In net = Mininet() # Create a switch switch = net.addSwitch('s1', cls=OVSSwitch) # Create two hosts host1 = net.addHost('h1', cls=Host, ip='10.0.0.1/24') host2 = net.addHost('h2', cls=Host, ip='10.0.0.2/24') # net.addLink(host1, switch) net.addLink(host2, switch) # 网 net.start() # Allow interoperability between the host net.pingAll() # Stop network net.stop() In this example, we first created a Mininet object.Then, we use the `addswitch ()` method to create a switch, and use the `addhost ()` method to create two hosts.Next, we connect these nodes with the `addlink ()` method to form a topology structure.Then, use the `Start ()` method to start the network, and use the `pingall ()` method to test the connectivity between the host.Finally, use the `Stop ()" method to stop the network. It should be noted that this is just a simple example code. The Mininet class library is very flexible. Users can make various customization and configuration according to their needs.By using the Mininet library, users can easily create and manage the virtual network experimental environment, and develop and test various network applications.