Actually, any type of dogs, that are big like German Shepherd, Labrador, Golden Retriever, St. Bernard, even bulldogs has the capacity to protect your home. These dogs are smarter than the regular one and they are totally loyal to their owner, despite some physical pain they sometimes felt and experience. They can detect something strange even when there are animals that not of their kind and some stranger will enter the house. They have the capacity to protect you from the harm that you will meet when you are with them.They could be train as well. When they are trained, surely they will be more smarter on how they will able to protect you. I hope you get one of these dogs because they can fight just to protect you and love you more than the special person you have.