# Source and Destination NAT
**URL:** https://forum.networklessons.com/t/source-and-destination-nat/2943
**Category:** IP Routing
**Created:** [February 14, 2018, 12:07pm UTC](https://forum.networklessons.com/t/source-and-destination-nat/2943 "2018-02-14T12:07:08Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@patil.sushanth68](https://forum.networklessons.com/u/patil.sushanth68)
#### Post date: [February 14, 2018, 12:07pm UTC](https://forum.networklessons.com/t/source-and-destination-nat/2943/1 "2018-02-14T12:07:09Z")
Hi,
Can you explain Source and Destination Nat in ASA and also in IOS with a scenario… Please…
---
### Author:  [@ReneMolenaar](https://forum.networklessons.com/u/ReneMolenaar)
#### Post date: [March 5, 2018, 11:26am UTC](https://forum.networklessons.com/t/source-and-destination-nat/2943/2 "2018-03-05T11:26:51Z")
Hi Sushanth,
Source NAT is typically used for Internet access where we translate the source address of a host to the public IP address of our router. Here is an example for Cisco IOS and ASA:
[https://networklessons.com/cisco/ccie-enterprise-infrastructurehow-to-configure-pat-on-cisco-ios-router/](https://networklessons.com/cisco/ccie-enterprise-infrastructurehow-to-configure-pat-on-cisco-ios-router/)
> **[Cisco ASA PAT Configuration](https://networklessons.com/cisco/asa-firewall/cisco-asa-pat-configuration)**
>
> This lesson explains how to configure and verify Port Address Translation (PAT) on your Cisco ASA Firewall.
Destination NAT is typically used for load balancing. We translate the destination when the packet goes from the outside to the inside. I don’t have a complete lesson for this but here is a quick example for Cisco IOS. Here’s the config of the NAT router:
```
hostname R1
!
ip cef
!
interface GigabitEthernet0/1
ip address 192.168.12.254 255.255.255.0
ip nat inside
!
interface GigabitEthernet0/2
ip address 192.168.1.254 255.255.255.0
ip nat outside
!
!
ip nat pool TELNET_SERVERS 192.168.12.1 192.168.12.2 prefix-length 24 type rotary
ip nat inside destination list PUBLIC_IP pool TELNET_SERVERS
!
ip access-list standard PUBLIC_IP
permit 172.16.1.1
!
end
```
We have two telnet servers, 192.168.12.1 and 192.168.12.2. This router can use 172.16.1.1 on the outside, this could be a public IP.
When a device on the outside (192.168.1.1) connects to 172.16.1.1, the first time you get:
```
R1#
NAT*: s=192.168.1.1, d=172.16.1.1->192.168.12.1 [47462]
```
And the second time:
```
R1#
NAT*: s=192.168.1.1, d=172.16.1.1->192.168.12.2 [11370]
```
So it gets load balanced to 192.168.12.1 first, then to 192.168.12.2.
Hope this is helpful!
Rene