Generally, this dog breed looks huge and scary so it protects you without training.
Akita's loyalty is extended to their owners so it do anything to protect their loving human families.
Dobermans' loyalty is unyielding so it does not require training to guard their owners.
Rottweiler is very courageous and strong build which makes them more protective.
Boxer dog breed always displays great courage and shows a fearless attitude towards intruders.
Generally, Bullmastiff doesn't back down from intruders which makes it excellent for those looking untrained protector.
German Shepherd has a great ability to assess danger and it easily identifies potential threats.
They considered as best protectors in the world and they are excellent choices for execution protection.