The interior routing protocols like OSPF and EIGRP or RIP use multicast or broadcast addressing for routing protocol traffic. Traditionally IPSec carries only unicast IP traffic. So we have not been able to run routing protocols over IPSec connections. The traditional solution has been to run IPSec with GRE which allows multicast and enables routing protocols. Cisco has introduced an enhancement in very recent code which enables running routing protocols over IPSec without needing GRE. If you are interested in this look for Virtual Tunnel Interface.
As a side note BGP runs over TCP and sends routing protocol traffic as unicast IP to specifically configured neighbors. This is why it has been possible to run BGP over IPSec. There is no dynamic neighbor discovery in BGP. One of the reasons that OSPF and EIGRP use multicast addressing is that it allows them to have dynamic neighbor discovery. And multicast addressing is the reason why they have not traditionally run over IPSec.
We have 3 identical switches configured by someone else and would like to claim some of the Gigabit ports(G1/G2/G3/G4) for use on servers. When we try to change the wiring and configuration, we run in to connectivity issues. Attached is a des...
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...