If there is a nice fence, (and I hope there is), you should be safe...but the barking...terrible. Obviously the dog believes you have invaded HIS territory.
It is your neighbor who must address the territorial behavior in his own dog. Only he, as the dog owner, can cause the dog to be trained not to be aggressive.
@CastorTroy Dogs sense fear. They can smell it. If your neighbor is afraid of his own dog, he has no business owning it, because he won't be able to control it if there is a problem.
If there are ANY problems you need to start calling it in to animal control, or the police.
@CastorTroy Then he really messed up somewhere along the way. There are bad or mislead owners, even with the best of intentions.
Especially if you have one of the strong large intelligent breeds, you have to be alpha, calm, stable and confident leader. Otherwise the dog will lead YOU. Sounds like your neighbour is the Beta here. And that is very BAD for everyone involved. Because an unbalanced dog has erratic energy and behavior. Exercise, discipline and love, in that order.