Whole idea for that article came from real environment. At home I have DrayTek Vigor 2850n as my broadband router (and in fact it is really nice piece of equipment). Same time I’m using some Cisco equipment located in remote Lab for testing purposes. Remote Lab is connected to Intrenet and before to get access to devices and systems located there I was using EzVPN. However, as Lab has Cisco ISR as main router I thought, why not to establish L2L IPsec between my home network and remote Lab. Now, question how to do that. I have DrayTek on one end and Cisco ISR on the other. After few attempts, mis-configurations and troubleshooting it did work quite well in fact. So, here it is.

Here is what needs to be achieved:

Equipment available:

• Cisco ISR 2811 – on the left side of the diagram – internal network 10.255.0.0/24
• DrayTek Vigor 2850n – on the right side of the diagram – internal network 10.130.1.0/24

Goal:

• Establish IPsec VPN Tunnel between Cisco and DrayTek to make communication available between 10.255.0.0/24 and 10.130.1.0/24.

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