With the BGP advertisement my subnet is reachable via internet and can reach anywhere via internet. Other 44 networks can reach my subnet as long as they are also advertised via BGP or have appropriate NAT rules to allow internet access. I can reach any BGP advertised 44 net addresses. However, I should not be able to reach any non-BGP advertised 44 net addresses unless there is a gateway (at USCD?) that allows for access to IPIP only 44 networks from 44 networks.
I guess I don’t know the network topology of the 44 net or the functions that are provided at the UCSD gateway.
I assumed that in order to reach IPIP only networks I would have to also establish IPIP tunnelling from each 44 host or gateway using subnets of my BGP advertised subnet.
Adi
Because you are advertising a route to your subnet via BGP, packets addressed to that subnet will go to you directly and will not reach the gateway at UCSD, and so therefore cannot reach you over a tunnel.
- Brian