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'''Prerequisites''':
'''Prerequisites''':
* Two RUTxxx routers of any type (excluding [[RUT850]])
* Two RUTxxx routers of any type (excluding [[RUT850]])
* Both routers must have a Public Static or Public Dynamic IP addresses
* At least one router must have a Public Static or Public Dynamic IP address
* At least one end device (PC, Laptop, Tablet, Smartphone) to configure the routers
* At least one end device (PC, Laptop, Tablet, Smartphone) to configure the routers
* (Optional) A second end device to configure and test remote LAN access
* (Optional) A second end device to configure and test remote LAN access
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There will be two IPsec configuration schemes presented. Although the second scheme is only an extension of the first one. Therefore, to configure the second scheme, you will have to configure the first as well.
There will be two IPsec configuration schemes presented. Although the second scheme is only an extension of the first one. Therefore, to configure the second scheme, you will have to configure the first as well.


'''configuration scheme 1''':
'''Configuration scheme 1''':


[[File:Configuration examples ipsec scheme 1.png]]
[[File:Configuration examples ipsec scheme 1.png]]


The figure above above depicts two RUTxxx routers (RUT1 and RUT2) connected by an IPsec tunnel via the Internet.
The figure above depicts two RUTxxx routers (RUT1 and RUT2) connected by an IPsec tunnel via the Internet.
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'''configuration scheme 2''':
'''Configuration scheme 2''':


[[File:Configuration examples ipsec scheme.png]]
[[File:Configuration examples ipsec scheme 2.png]]


As mentioned earlier, ''configuration scheme 2'' (figure above) is an extension of ''configuration scheme 1''. While ''configuration scheme 1'' only depicts a connection between two IPsec instances, you can see that in ''configuration scheme 2'' additionally contains two end devices ('''END1''' and '''END2'''), each connected to a separate router's LAN. When this scheme is realized, not only will the two routers be able to communicate with each other, the end devices will also be reachable to one another and from each router.
As mentioned earlier, ''configuration scheme 2'' (figure above) is an extension of ''configuration scheme 1''. While ''configuration scheme 1'' only depicts a connection between two IPsec instances, you can see that ''configuration scheme 2'' additionally contains two end devices ('''END1''' and '''END2'''), each connected to a separate router's LAN. When this scheme is realized, not only will the two routers be able to communicate with each other, but the end devices will also be reachable to one another and from each router.


It should also be noted the connection type used is '''Tunnel''' and not '''Transport'''. Tunnel protects the internal routing information by encrypting the IP header of the original packet. The original packet is encapsulated by a another set of IP headers. Transport encrypts only the payload and Encapsulating Security Payload (ESP) trailer; so the IP header of the original packet is not encrypted. Transport mode is usually used when another tunneling protocol (such as [[VPN#GRE_Tunnel|GRE]], [[VPN#L2TP|L2TP]]) is used to first encapsulate the IP data packet, then IPsec is used to protect the GRE/L2TP tunnel packets.
It should also be noted the connection type used is '''Tunnel''' and not '''Transport'''. Tunnel protects the internal routing information by encrypting the IP header of the original packet. The original packet is encapsulated by a another set of IP headers. Transport encrypts only the payload and Encapsulating Security Payload (ESP) trailer; so the IP header of the original packet is not encrypted. Transport mode is usually used when another tunneling protocol (such as [[VPN#GRE_Tunnel|GRE]], [[VPN#L2TP|L2TP]]) is used to first encapsulate the IP data packet, then IPsec is used to protect the GRE/L2TP tunnel packets.


Tunnel is more is more widely implemented in site-to-site VPN scenarios and supports NAT traversal, that's why we chose it for the example.
Tunnel is more widely implemented in site-to-site VPN scenarios and supports NAT traversal. For instructions on how to configure Transport mode, you may want to check out our '''[[L2TP over IPsec]]''' article.


==Router configuration==
==Router configuration==
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* Login to the router's WebUI and go to '''Services → VPN → IPsec'''. Enter a custom name (for this example we use ''RUT1'') for the IPsec instance click the "Add" button:
* Login to the router's WebUI and go to '''Services → VPN → IPsec'''. Enter a custom name (for this example we use ''RUT1'') for the IPsec instance click the "Add" button:


[[File:Creating an ipsec instance part 1 v1.png]]
[[File:Ipsec1.png|alt=|1126x1126px]]
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* Click the "Edit" button located next to the newly created instance:
* Click the "Edit" button located next to the newly created instance:


[[File:Creating an ipsec instance part 2 v1.png]]
[[File:Ipsec2.png|alt=|1129x1129px]]
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* You will be redirected to the instance's configuration window. From here we will discuss how to configure both instances (''RUT1'' and ''RUT2''). Creating a second instance is analogous to how we created the first one - just login to the second router and repeat the first two steps. Although not mandatory, we recommend that you use a distinct name for the second instance (for this example we use ''RUT2'') for easier management purposes. <br> The specifics of both configurations are described in the figure below:
* You will be redirected to the instance's configuration window. From here we will discuss how to configure both instances (''RUT1'' and ''RUT2''). Creating a second instance is analogous to how we created the first one - just login to the second router and repeat the first two steps. Although not mandatory, we recommend that you use a distinct name for the second instance (for this example we use ''RUT2'') for easier management purposes. <br> The specifics of both configurations are described in the figure below:


[[File:Creating an ipsec instance part 3 v2.png]]
[[File:Ipsec3.png|alt=|1150x1150px]]


* Below are explanations of the parameters highlighted in the figure above. Other parameters (not highlighted) are defaults. You can find descriptions for these parameters in the '''[[VPN#IPsec|VPN manual page, IPsec section]]'''.
* Below are explanations of the parameters highlighted in the figure above. Other parameters (not highlighted) are defaults. You can find descriptions for these parameters in the '''[[VPN#IPsec|VPN manual page, IPsec section]]'''
** '''Enable''' - enables the IPsec instance
**'''Enable''' - enables the IPsec instance
** '''Local IP address/Subnet mask''' - LAN IP address/Subnet mask of the router on which the IPsec instance is configured
** '''Remote Endpoint''' - the Public IP address of the opposite router, leaving empty will force IPSec to only accept connections.
** '''Pre shared key''' - a shared password used for authentication between the peers. The value of this field must match on both instances
** '''Pre shared key''' - a shared password used for authentication between the peers. The value of this field must match on both instances
** '''Remote VPN endpoint''' - the Public IP address of the opposite router
**'''Local Identifier''' - private IP address of your router.
** '''Remote IP address/Subnet mask''' - LAN IP address/Subnet mask of the opposite router
**'''Remote Identifier''' - private IP of the opposite router.
** '''Enable keepalive''' - enables the tunnel's keep alive function. When enabled, the instance sends ICMP packets to the specified host at the specified frequency. If no response is received, the instance attempts to restart the connection
** '''Local subnet''' - routers local subnet.
*** '''Host''' - hostname or IP address to which ICMP packets will be sent to. Best to use a hostname/IP address belonging to the opposite instance's LAN. For this example we just use the other router's LAN IP address
** '''Remote subnet''' - opposite routers subnet.
*** '''Ping period (sec)''' - the period (in seconds) at which ICMP packets will be sent to the specified host
** '''Allow WebUI access''' - when checked, allows WebUI access for hosts from the opposite instance
'''NOTE''': remember to replace certain parameter values (like IP addresses) with your own relevant data.
'''NOTE''': remember to replace certain parameter values (like IP addresses) with your own relevant data.
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* The last in configuring the IPsec intances is '''Phase settings'''. For this example we left the default Phase settings. If you're planning to change Phase settings, make sure they match with the Phase settings of the incoming connection:
* The last step in configuring the IPsec instances is '''Proposal settings'''. Make sure they match with the Phase settings ('''both Phase 1 and Phase 2''') of the incoming connection:


[[File:Creating an ipsec instance part 4 v1.png]]
[[File:Ipsec4.png|alt=|1572x1572px]]


When you're finished with the configuration, don't forget to click the "Save" button.
When you're finished with the configuration, don't forget to click the "Save" button.


===Remote LAN access===
<!--===Remote LAN access===
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Once your IPsec tunnel is operational, you can configure remote access to LAN devices via the tunnel as referenced in ''[[IPsec_configuration_examples#Configuration_overview_and_prerequisites|configuration scheme 2]]''. This section provides a description on how to do just that.
Once your IPsec tunnel is operational, you can configure remote access to LAN devices via the tunnel as referenced in ''[[IPsec_configuration_examples#Configuration_overview_and_prerequisites|configuration scheme 2]]''. This section provides a description on how to do just that.
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*
* In order for the remote LAN access to work, we'll need to add a couple of static routes - one in each router. Login to a router's WebUI and navigate to '''Network → Routing → Static Routes'''. Continuing our example, below is figure depicting the static route configuration for '''RUT1''':
[[File:How to configure static routes for ipsec rut1 v2.png]]
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* And for '''RUT2''':
 
[[File:How to configure static routes for ipsec rut2 v2.png]]
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* To sum up, for our current purposes select '''MAIN''' Routing table and '''LAN''' interface in both routers; under Destination address, specify the LAN address of the opposite router; under Netmask, specify '''255.255.255.0''' unless your configuring a different size network (more on Netmasks '''[[What_is_a_Netmask%3F|here]]'''); under Gateway, specify the current router's LAN IP address; you can leave the Metric as 0 unless your own specific configuration requires otherwise.
 
'''NOTE''': make sure to add a new entry in the Static Routes table when you configure custom routes. You can configure existing routes, but take note that this may cause backup WAN to function improperly or not at all.
-->


==Testing the setup==
==Testing the setup==
If you've followed all the steps presented above, your configuration should be finished. But as with any other configuration, it is always wise to test the setup in order to make sure that it works properly. In order to test an IPsec connection, login to one of the routers' WebUIs and go to '''Services → CLI'''. Login with user name: '''root''' and the router's admin password. From there you should then be able to '''ping''' the opposite instance's LAN IP address. To use a ping command, type '''ping <ip_address>''' and press the "Enter" key on your keyboard:
[[File:Configuration example ipsec testing.png]]
You can also test if LAN access is working the same way. Instead of pinging the opposite instance's LAN IP address, ping one of the end device's IPs. One common issue that can be encountered here is that the end devices '''might need their DHCP leases renewed'''. There are many methods of accomplishing this, but the easiest and most accessible way is to simply disconnect and reconnect the LAN cable to device or the router that it's connected to.
If the ping requests are successful, congratulations, your setup works! If not, we suggest that you review all steps once more.


==See also==
==See also==
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* Other types of VPNs suported by RUTxxx devices:
* Other types of VPNs suported by RUTxxx devices:
** [[OpenVPN configuration examples]]
** [[OpenVPN configuration examples]]
** [[GRE Tunnel configuration examples]]
** [[PPTP configuration examples]]
** [[PPTP configuration examples]]
** [[L2TP configuration examples]]
** [[L2TP configuration examples]]