POX and Python network programming (Pox and Python Network Programming)

POX and Python network programming POX is an open source network controller platform based on Python, which is used to build and manage software definition networks (SDN).It provides a set of strong libraries and tools to write network applications and achieve comprehensive control of the network environment. Python is a powerful and easy -to -learn programming language. It is closely integrated with POX, making network programming easier and flexible.In this article, we will explore how to use Pox and Python for network programming and provide relevant configuration and complete programming code. The installation and configuration process of POX is relatively simple.First, make sure that Python and Git have been installed.Then, get the latest version of the POX from GitHub through the following command: git clone https://github.com/noxrepo/pox.git After downloading, you can start POX through the following command: ./pox.py Now, let's write a simple POX application for sending and receiving data packets through the TCP/IP protocol. python from pox.core import core from pox.lib.util import dpid_to_str import pox.openflow.libopenflow_01 as of log = core.getLogger() class MyController(object): def __init__(self): core.openflow.addListeners(self) def _handle_ConnectionUp(self, event): dpid = dpid_to_str(event.dpid) log.info("Switch %s connected", dpid) msg = of.ofp_flow_mod() msg.match.dl_type = 0x0800 # IPv4 msg.actions.append(of.ofp_action_output(port=of.OFPP_FLOOD)) event.connection.send(msg) def _handle_PacketIn(self, event): packet = event.parsed log.info("Packet received: %s", packet) msg = of.ofp_packet_out() msg.data = event.ofp msg.actions.append(of.ofp_action_output(port=of.OFPP_FLOOD)) event.connection.send(msg) def launch(): core.registerNew(MyController) The above code creates a POX application called `MyController`.It creates a listener through the core method provided by POX and implements the method of `_handle_connectionup` and` _handle_packetin` to handle the switch connection and data packet receiving events. In the method of `_handle_connectionup`, we obtain the ID of the switch and send the OFPT_FLOW_MOD message to generalize the received IPv4 packet flood to all ports. In the method of `_handle_packetin`, we simply print the received data packets and use Office_Packet_out messages to pan to all ports. Finally, the `launch` method register the` MyController` as the controller of the POX. To run this application, you can start the POX through the following command, add the application to the controller: ./pox.py mycontroller Before running POX, make sure there is a virtual network environment that supports the OpenFlow protocol and connect the switch to this environment. Writing network applications through POX and Python can achieve various functions, such as traffic monitoring, network routing management, network security, etc.The combination of POX and Python makes network programming easier and flexible, and can quickly develop high -performance SDN applications according to actual needs. It is hoped that this article can help readers understand the basic knowledge of POX and Python network programming, and provide a detailed explanation for relevant configuration and programming code.