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site-to-site VPN, interesting traffic on one side are public IP's

I have configured may site-to-site VPN's in the past, but the interesting traffic on both sides has all been IP's in the private IP range.  A vendor we host software with needs a VPN to my office.  The interesting traffic on my side are private IP's (,, but the interesting traffic on their side is a public IP (  I've never configured a site-to-site VPN where the interesting traffic on one side is a public IP address.  Is this configured the same as a VPN where both sides interesting traffic is private addresses?  What would the nonat look like with the destination being a public IP?  Any assistance would be greatly appreciated.  Thanks.
CiscoVPNInternet Protocol Security

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8/22/2022 - Mon
Rob Williams

Is it actualy ?  If so I am doubtful it is a true public IP but rather some device on the network with a sample configuration.  Perhaps something like a rougue router, or a printer, but the printer is actaully being used via the USB connecion rather than the Ethernet.

Can you locate a MAC address associated with it using arp -a ?  If so you can look up the manufacture of the NIC.  That sometimes helps if it is sometjing like a Linksys router.

You wouldn't expect me to post the actual public address would you:) is just a reference to a public address.  Its not the actual address.

BTW, both sides of the VPN are Cisco ASA's.  I forgot to mention that in the question
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William Peck
Rob Williams

No problem, you posted LAN IP's so I wonderd, lots of people do post the public IP (unfortunately) thus why I asked "Is it actualy".

For this VPN, my interesting traffic are two private IP's (,, the destination IP is a public IP Address.  I just need to know if the VPN is configured the same way.
Sandeep Gupta

actually this is possible but you have to do natting,

on public IP side you have to mapp your private IPs
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Marius Gunnerud

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Thanks.  It was configured the exact same way.