NAT的转换方式

在Cisco NAT 路由器中可以配置多种形式的NAT地址转换，但总体说就是两种静态和动态，在动态的nat中又有一种特殊的nat形式，那就是重载（Overloading NAT），也称为PAT端口地址转换，
静态NAT是指在本地局域网中一对一的映射到公网IP。
动态nat是把一个非注册地址动态映射到一个注册IP地址池的一个地址。
重载或复用NAT,PAT也是动态的一种形式。与IP地址的不同端口组合，把多个非注册IP地址映射到一个注册IP地址。
下面示例静态跟动态
R2(config)#do show runn
Building configuration...
Current configuration : 687 bytes
version 12.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
hostname R2
spanning-tree mode pvst
interface FastEthernet0/0
 ip address 10.1.1.1 255.255.255.0
 ip nat inside
 duplex auto
 speed auto
!
interface FastEthernet0/1
 ip address 61.159.62.130 255.255.255.248
 ip nat outside
 duplex auto
 speed auto
interface Vlan1
 no ip address
 shutdown
ip nat inside source static 10.1.1.2 61.159.62.130 #静态直接一对一对应
ip nat inside source static 10.1.1.3 61.159.62.131
ip classless
ip route 0.0.0.0 0.0.0.0 61.159.62.129

动态NAT。
R2(config)#do show runn
Building configuration...


Current configuration : 800 bytes
version 12.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
hostname R2

spanning-tree mode pvst
interface FastEthernet0/0
 ip address 10.1.1.1 255.255.255.0
 ip nat inside
 duplex auto
 speed auto
interface FastEthernet0/1
 ip address 61.159.62.130 255.255.255.248
 ip nat outside
 duplex auto
 speed auto
interface Vlan1
 no ip address
 shutdown
ip nat pool winsnet0 61.159.62.131 61.159.62.135 netmask 255.255.255.248 #（动态地址池）
ip nat inside source list 1 pool winsnet0  #可以添加创建多个地址池如winsnet1 ，winsnet3
ip nat inside source static tcp 10.1.1.3 80 61.159.62.133 80
ip classless
ip route 0.0.0.0 0.0.0.0 61.159.62.129
access-list 1 permit 10.1.1.0 0.0.0.255
line con 0
line aux 0
line vty 0 4
 login
end