The blacklist represents itself a list or register of entities which are denied privileges, service, mobility, access and admission due to these or other reasons. This function blocks all connections from the subscribers who are in the list.
We are all human and therefore we all need to rest. Foreign countries attract people, because "the grass is always greener at neighbors’ yard." But while abroad, we also want to keep in touch with family and friends in order to tell any news or just share experiences.