Consider a distance vector protocol using split horizon and `periodic updates`. Assume that the link `B-C` fails. `B` and `C` update their local routing table but they will only advertise it at the end of their period. Select one ordering for the`periodic updates` and every time a router sends its distance vector, indicate the vector sent to each neighbor and update the table above. How many periods are required to allow the network to converge to a stable state ?