实验5 开源控制器实践——POX

实验5 开源控制器实践——POX

基础实验

1. hub
   

分析：
由于在hub模式下，采取广播帧的模式，交换机每收到一帧，会向所有端口进行广播，因而h1发给h2的数据包在h3的端口也能监听到

2. switch
   

分析：
由于在自学习模式下，交换机会根据mac高速缓存信息进行发送数据包，因而在实验过程中，对于h1发给h2的数据包，h3只能捕捉到h1对h2的arp请求，并不能捕捉到数据包

3. 流程图
   

进阶实验

1. 自定义一个POX模块SendFlowInSingle3

from pox.core import core
import pox.openflow.libopenflow_01 as ofclass SendFlowInSingle3(object):def __init__(self):core.openflow.addListeners(self)def _handle_ConnectionUp(self, event):msg = of.ofp_flow_mod()  msg.priority = 1msg.match.in_port = 1 msg.actions.append(of.ofp_action_output(port=2)) msg.actions.append(of.ofp_action_output(port=3)) event.connection.send(msg)msg = of.ofp_flow_mod()  msg.priority = 1msg.match.in_port = 2 msg.actions.append(of.ofp_action_output(port=1)) msg.actions.append(of.ofp_action_output(port=3))  event.connection.send(msg)msg = of.ofp_flow_mod() msg.priority = 1msg.match.in_port = 3  msg.actions.append(of.ofp_action_output(port=1))  msg.actions.append(of.ofp_action_output(port=2)) event.connection.send(msg)def launch():core.registerNew(SendFlowInSingle3)

结果：

2. 硬超时功能
   2.1 利用1编写的代码，手工开启、断开、再开启

from pox.core import core
import pox.openflow.libopenflow_01 as ofclass SendPoxHardTimeOut(object):def __init__(self):core.openflow.addListeners(self)def _handle_ConnectionUp(self, event):msg = of.ofp_flow_mod()  msg.priority = 2msg.match.in_port = 1 msg.hard_timeout = 10event.connection.send(msg)msg = of.ofp_flow_mod()  msg.priority = 1msg.match.in_port = 1 msg.actions.append(of.ofp_action_output(port=2)) msg.actions.append(of.ofp_action_output(port=3)) event.connection.send(msg)msg = of.ofp_flow_mod()  msg.priority = 2msg.match.in_port = 2 msg.hard_timeout = 10event.connection.send(msg)msg = of.ofp_flow_mod()  msg.priority = 1msg.match.in_port = 2 msg.actions.append(of.ofp_action_output(port=1)) msg.actions.append(of.ofp_action_output(port=3))  event.connection.send(msg)msg = of.ofp_flow_mod()  msg.priority = 2msg.match.in_port = 3 msg.hard_timeout = 10event.connection.send(msg)msg = of.ofp_flow_mod() msg.priority = 1msg.match.in_port = 3  msg.actions.append(of.ofp_action_output(port=1))  msg.actions.append(of.ofp_action_output(port=2)) event.connection.send(msg)def launch():core.registerNew(SendPoxHardTimeOut)

2.2 直接运行SendPoxHardTimeOut

实验总结

本次实验主要学习POX控制器的使用方法，通过实验学习，我对比了集线器和交换机传输帧的区别，切实地感受到交换机自学习算法能够有效地减少广播风暴。并且，通过此次实验，我了解了如何通过编写代码实现硬实时功能、下发流表功能，颇有收获。