How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Applicable Version: 10.00 onwards

Overview

IPSec is an end-to-end security scheme operating in the Internet Layer of the Internet Protocol Suite. It is

used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways

(network-to-network), or between a security gateway and a host (network-to-host).

Cyberoams IPSec VPN offers site-to-site VPN with cost-effective site-to-site remote connectivity,

eliminating the need for expensive private remote access networks like leased lines, Asynchronous

Transfer Mode (ATM) and Frame Relay. This article describes a detailed configuration example that

demonstrates how to set up a site-to-site IPSec VPN connection between the two networks using

preshared key to authenticate VPN peers.

Scenario

Configure a site-to-site IPSec VPN connection between Site A and Site B by following the steps given

below. In this article, we have used the following parameters to create the VPN connection.

Network Parameters

Local Network details Local Server (WAN IP address) 14.15.16.17

Local LAN address 10.5.6.0/24

Remote Network details Remote VPN server (WAN IP address) 22.23.24.25

Remote LAN Network 172.23.9.0/24

Site A Configuration

The configuration is to be done from Site As Cyberoam Web Admin Console using profile having read-

write administrative rights for relevant feature(s).

How To Establish Site-to-Site VPN Connection

using Preshared Key

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Step 1: Create IPSec Connection

To create a new IPSec connection, go to VPN > IPSec > Connection and click Add. Create the

connection using the following parameters.

Parameter Description

Parameter Value Description

Name SiteA_to_SiteB Name to identify the IPSec Connection

Connection Type Site to Site

Select Type of connection.

Available Options:

Remote Access

Site to Site

Host to Host

Policy DefaultHeadOffice Select policy to be used for connection

Action on VPN Restart Respond Only

Select the action for the connection.

Available options:

Respond Only

Initiate

Disable

Authentication details

Authentication Type Preshared Key Select Authentication Type. Authentication of user

depends on the connection type.

Preshared Key 123456789 Preshared key should be the same as that configured in

remote site.

Endpoints Details

Local PortB-14.15.16.17 Select local port which acts as end-point to the tunnel

Remote 22.23.24.25 Specify IP address of the remote endpoint.

Local Network Details

Local Subnet 10.5.6.0/24 Select Local LAN Address. Add and Remove LAN

Address using Add Button and Remove Button

Remote Network Details

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Remote LAN Network 172.23.9.0/24 Select Remote LAN Address. Add and Remove LAN

Address using Add Button and Remove Button

Click OK to create IPSec connection.

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Step 2: Activate Connection

On clicking OK, the following screen is displayed showing the connection created above.

Click under Status (Active) to activate the connection.

Site B Configuration

The configuration is to be done from Site Bs Cyberoam Web Admin Console using profile having read-

write administrative rights for relevant feature(s).

Step 1: Create IPSec Connection

To create a new IPSec connection, go to VPN > IPSec > Connection and click Add. Create the

connection using the following parameters.

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Parameter Description

Parameter Value Description

Name SiteB_to_SiteA Name to identify the IPSec Connection

Connection Type Site to Site

Select Type of connection.

Available Options:

Remote Access

Site to Site

Host to Host

Policy DefaultBranchOffice Select policy to be used for connection

Action on VPN

Restart Initiate

Select the action for the connection.

Available options:

Respond Only

Initiate

Disable

Authentication details

Authentication Type Preshared Key Select Authentication Type. Authentication of user

depends on the connection type.

Preshared Key 123456789 Preshared key should be the same as that configured in

remote site.

Endpoints Details

Local PortB-22.23.24.25 Select local port which acts as end-point to the tunnel

Remote 14.15.16.17 Specify IP address of the remote endpoint.

Local Network Details

Local Subnet 172.23.9.0/24 Select Local LAN Address. Add and Remove LAN

Address using Add Button and Remove Button

Remote Network Details

Remote LAN Network 10.5.6.0/24 Select Remote LAN Address. Add and Remove LAN

Address using Add Button and Remove Button

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

Step 2: Activate and Establish Connection

On clicking OK, the following screen is displayed showing the connection created above.

Click under Status (Active) and Status (Connection).

How To Establish Site-to-Site IPSec VPN Connection using Preshared key

The above configuration establishes an IPSec connection between Two (2) sites.

Note:

Make sure that Firewall Rules that allow LAN to VPN and VPN to LAN traffic are configured.

In a Head Office and Branch Office setup, usually the Branch Office acts as the tunnel initiator and Head

Office acts as a responder due to following reasons:

Since Branch Office or other Remote Sites have dynamic IPs, Head Office is not able to initiate the

connection.

As there can be many Branch Offices, to reduce the load on Head Office it is a good practise that

Branch Offices retries the connection instead of the Head Office retrying all the branch office

connections.

Document Version: 2.1 22 February, 2014