实验5：开源控制器实践——POX

（一）基本要求

1.搭建下图所示SDN拓扑，协议使用Open Flow 1.0，控制器使用部署于本地的POX（默认监听6633端口）

2.阅读Hub模块代码，使用 tcpdump 验证Hub模块；

h1 ping h2

hi ping h3

3.(1)阅读L2_learning模块代码，画出程序流程图，使用 tcpdump 验证Switch模块。

（2）使用 tcpdump 验证Switch模块

h1 ping h2

h1 ping h3

进阶要求

1.重新搭建（一）的拓扑，此时交换机内无流表规则，拓扑内主机互不相通；编写Python程序自定义一个POX模块SendFlowInSingle3，并且将拓扑连接至SendFlowInSingle3（默认端口6633），实现向s1发送流表规则使得所有主机两两互通。

删除流表ping

添加流表PING通

from pox.core import core
import pox.openflow.libopenflow_01 as of
from pox.openflow.of_json import *


def _handle_ConnectionUp(event):
    msg = of.ofp_flow_mod()
    msg.priority = 1
    msg.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 = 1
    msg.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 = 1
    msg.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.openflow.addListenerByName("ConnectionUp", _handle_ConnectionUp)

硬件超时功能

from pox.core import core
import pox.openflow.libopenflow_01 as of
from pox.openflow.of_json import *


def _handle_ConnectionUp(event):
    msg = of.ofp_flow_mod()
    msg.priority = 1
    msg.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 = 1
    msg.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 = 1
    msg.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.openflow.addListenerByName("ConnectionUp", _handle_ConnectionUp)