public ip over private connection - how does it works ?

[SJ K]

Hi all

I have a private cross-connection with a service provider

This private connection is connected from my firewall to their router and the L3 IP range /30 for this segment is private

I also realized that the designated application IP provided on their end to connect to - over this private connection is a public IP

The source IP i am using is actually still a private IP but yet the destination i am connecting to is a public IP and this is done over a private cross-connect with a private /30 transit network

Can a public IP transverse a private network ? I mean this cross-connection is not facing the internet - how does it work ?

When doing a EBGP with a service provider - it seems to be same case as well - the network segment connecting to the service provider is a private segment, but the destination IP is a public IP and it seems i would need to provide a public IP as well but my application is not a internet facing application

Thank you

[Jon Marshall]

As long as the L3 devices have routing entries then it makes no difference what the IP is. 

Of course the internet routers do not have routing entries for private IPs so if you were talking to the internet you would need NAT but with a provider on your own or a shared network as long as they have setup the routing correctly then it should work. 

Jon