Hi Keith,
Will surely need some clarification on your query.
If you need to bring a VPN tunnel up with remote peer , then they need to know your public IP so that they know where to terminate the VPN tunnel.
Additionally, once the tunnel comes up , you ll be sending traffic over it and you need to know your local IPs and remote IPs which will be behind remote VPN device.
Hope this helps.
Regards,
Dinesh Moudgil
P.S. Pleae rate helpful posts.
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