An aggressive dog is usually very dominant and self assured and it is often the owner who is bitten when he attempts to make the dog do something it does not wish to do. Just as it is not necessary to have an aggressive dog, it is also not necessary to have a noisy dog to give the alarm when intruders come on to the property. The fable of the boy who cried wolf applies to the dog which creates noise so often that nobody takes any notice when he eventually barks at intruders. All dogs bark - with the exception of the Basenji and Native Dogs, but even they are not voiceless. How much a dog barks is due in part to it's breed and nature but mostly due to the training the dog has received.
Some breeds are more vocal than others - usually the more physically and mentally active breeds.
Large breeds are not more noisy - some of the more likely to bark are the smaller very active and alert breeds. Large dogs do have louder barks but they are also deeper in tone and may not carry as far or be any more annoying than a shriller bark from a small dog. All puppies should be taught that unnecessary barking is not allowed just as children are taught that continuos screaming and yelling is not allowed. When the puppy quietens it should be praised. Dogs do not develop a sense of territory under nine months of age and a puppy will be unlikely to bark at people coming onto it's property.