一、用户需求
用户有一台Cisco PIX 515E防火墙，一个网通的出口，一个电信的出口。现在要实现默认都往电信线路出去，而访问网通的网站时使用网通的线路出去。
二、实现要点
1、首先要收集网通的IP网段（这个可以在网络上搜索，或者电信的朋友要一份）；
2、在路由方面，由于Cisco PIX是偏向于防火墙的功能，因此PIX在路由方面是比较弱的无法通过策略路由来实现，在此我使用了默认路由往设成电信的网关，同时添加网通IP网段的静态路由。这样实现了两个出口路由的走向。
3、在NAT方面，要配置两条NAT，其中一条是通往网通的转换成网通的出口IP，另一条是通往电信的转换成电信的出口IP，这个NAT应该是网通的NAT要配置在电信NAT前面，否则将无法实现。
三、Cisco PIX双出口配置
3.1 环境描述
nameif ethernet0 outside security0
nameif ethernet1 inside security100
nameif ethernet5 teloutside security0
ip address outside 224.254.14.164 255.255.255.0
ip address inside 192.168.0.1 255.255.255.0
ip address teloutside 202.99.114.91 255.255.255.128
#备注：outside为网通线路出口；teloutside为电信线路出口；inside为内网接口；
3.2双出口实现
A、网通IP网段定义
object-group network wtnetwork
network-object 58.16.0.0 255.248.0.0
network-object 58.100.0.0 255.254.0.0
network-object 58.240.0.0 255.240.0.0
network-object 60.0.0.0 255.248.0.0
network-object 60.8.0.0 255.252.0.0
network-object 60.12.0.0 255.255.0.0
network-object 60.13.0.0 255.255.192.0
network-object 60.13.128.0 255.255.128.0
network-object 60.16.0.0 255.240.0.0
network-object 60.24.0.0 255.248.0.0
network-object 60.31.0.0 255.255.0.0
network-object 60.208.0.0 255.248.0.0
network-object 60.216.0.0 255.254.0.0
network-object 60.220.0.0 255.252.0.0
network-object 61.48.0.0 255.252.0.0
network-object 61.52.0.0 255.254.0.0
network-object 61.54.0.0 255.255.0.0
network-object 61.55.0.0 255.255.0.0
network-object 61.133.0.0 255.255.128.0
network-object 61.134.64.0 255.255.192.0
network-object 61.134.128.0 255.255.128.0
network-object 61.135.0.0 255.255.0.0
network-object 61.136.0.0 255.255.0.0
network-object 61.138.0.0 255.255.128.0
network-object 61.139.128.0 255.255.192.0
network-object 61.148.0.0 255.255.0.0
network-object 61.149.0.0 255.255.0.0
network-object 61.156.0.0 255.255.0.0
network-object 61.158.0.0 255.255.0.0
network-object 61.159.0.0 255.255.192.0
network-object 61.161.0.0 255.255.192.0
network-object 61.161.128.0 255.255.128.0
network-object 61.162.0.0 255.255.0.0
network-object 61.163.0.0 255.255.0.0
network-object 61.167.0.0 255.255.0.0
network-object 61.168.0.0 255.255.0.0
network-object 61.176.0.0 255.255.0.0
network-object 61.179.0.0 255.255.0.0
network-object 61.180.128.0 255.255.128.0
network-object 61.181.0.0 255.255.0.0
network-object 61.182.0.0 255.255.0.0
network-object 61.189.0.0 255.255.128.0
network-object 124.90.0.0 255.254.0.0
network-object 124.162.0.0 255.255.0.0
network-object 202.32.0.0 255.224.0.0
network-object 202.96.64.0 255.255.224.0
network-object 202.97.128.0 255.255.128.0
network-object 202.98.0.0 255.255.224.0
network-object 202.99.0.0 255.255.0.0
network-object 202.102.128.0 255.255.192.0
network-object 202.102.224.0 255.255.254.0
network-object 202.106.0.0 255.255.0.0
network-object 202.107.0.0 255.255.128.0
network-object 202.108.0.0 255.255.0.0
network-object 202.110.0.0 255.255.128.0
network-object 202.110.192.0 255.255.192.0
network-object 202.111.128.0 255.255.192.0
network-object 203.79.0.0 255.255.0.0
network-object 203.80.0.0 255.255.0.0
network-object 203.81.0.0 255.255.224.0
network-object 203.86.32.0 255.255.224.0
network-object 203.86.64.0 255.255.224.0
network-object 203.90.0.0 255.255.128.0
network-object 203.90.128.0 255.255.192.0
network-object 203.90.192.0 255.255.224.0
network-object 203.92.0.0 255.254.0.0
network-object 210.12.0.0 255.255.128.0
network-object 210.12.192.0 255.255.192.0
network-object 210.13.0.0 255.255.255.0
network-object 210.14.160.0 255.255.224.0
network-object 210.14.192.0 255.255.192.0
network-object 210.15.0.0 255.255.128.0
network-object 210.15.128.0 255.255.192.0
network-object 210.16.128.0 255.255.192.0
network-object 210.21.0.0 255.255.0.0
network-object 210.22.0.0 255.255.0.0
network-object 210.51.0.0 255.255.0.0
network-object 210.52.0.0 255.254.0.0
network-object 210.52.128.0 255.255.128.0
network-object 210.53.0.0 255.255.0.0
network-object 210.74.64.0 255.255.192.0
network-object 210.74.128.0 255.255.192.0
network-object 210.78.0.0 255.255.224.0
network-object 210.82.0.0 255.254.0.0
network-object 211.100.0.0 255.255.0.0
network-object 211.101.0.0 255.255.192.0
network-object 211.147.0.0 255.255.0.0
network-object 211.167.96.0 255.255.224.0
network-object 218.4.0.0 255.252.0.0
network-object 218.10.0.0 255.254.0.0
network-object 218.21.128.0 255.255.128.0
network-object 218.24.0.0 255.254.0.0
network-object 218.26.0.0 255.255.0.0
network-object 218.27.0.0 255.255.0.0
network-object 218.28.0.0 255.254.0.0
network-object 218.56.0.0 255.252.0.0
network-object 218.60.0.0 255.254.0.0
network-object 218.62.0.0 255.255.128.0
network-object 218.67.128.0 255.255.128.0
network-object 218.68.0.0 255.254.0.0
network-object 218.109.159.0 255.255.255.0
network-object 219.141.128.0 255.255.128.0
network-object 219.142.0.0 255.254.0.0
network-object 219.154.0.0 255.254.0.0
network-object 219.156.0.0 255.254.0.0
network-object 219.158.0.0 255.255.0.0
network-object 219.159.0.0 255.255.192.0
network-object 220.248.0.0 255.252.0.0
network-object 220.252.0.0 255.255.0.0
network-object 221.0.0.0 255.252.0.0
network-object 221.4.0.0 255.254.0.0
network-object 221.6.0.0 255.255.0.0
network-object 221.7.128.0 255.255.128.0
network-object 221.8.0.0 255.254.0.0
network-object 221.10.0.0 255.255.0.0
network-object 221.11.0.0 255.255.128.0
network-object 221.12.0.0 255.252.0.0
network-object 221.12.0.0 255.255.128.0
network-object 221.12.128.0 255.255.192.0
network-object 221.192.0.0 255.252.0.0
network-object 221.195.0.0 255.255.0.0
network-object 221.196.0.0 255.254.0.0
network-object 221.199.0.0 255.255.224.0
network-object 221.199.32.0 255.255.240.0
network-object 221.199.128.0 255.255.192.0
network-object 221.199.192.0 255.255.240.0
network-object 221.200.0.0 255.252.0.0
network-object 221.204.0.0 255.254.0.0
network-object 221.207.0.0 255.255.192.0
network-object 221.208.0.0 255.240.0.0
network-object 221.208.0.0 255.252.0.0
network-object 221.213.0.0 255.255.0.0
network-object 221.214.0.0 255.254.0.0
network-object 222.128.0.0 255.252.0.0
network-object 222.132.0.0 255.252.0.0
network-object 222.136.0.0 255.248.0.0
network-object 222.160.0.0 255.252.0.0
network-object 222.163.0.0 255.255.224.0
