Authentication - EIGRP, OSPF

["Tariq Sharif" <sharif.tariq@xxxxxxxxx>]

Hi there

Just wondering of someone can shed light on how EIGRP and OSPF
authentication work? Is each routing packet authenticated as it is exchnaged
between the routers or authentication only takes place at the neighbour
formation?

I think in the case of RIP v2 it routing packet by packet authernticaion
because there are no neighbours...?

Thanks

Tariq