I fear dogs like this every time I walk my dog.
I carry chemical mace + pepper spray, but I’m not sure if that would be enough.
Buy a gun
I'm hoping that it is possible to obtain a taser, legally or illegally. Our family pet at 40 pounds and with a "wus" personality would last seconds against a vicious dog, and I have one close by. It's a rottweiler I call Cujo for obvious reasons, and in the past, on several occasions he has actually tried to exit through the wooden fence retaining him.
I want to make sure that any confrontation between us is as unequal as possible -- in our favor.
The dog is an attack dog, but I refuse to be intimidated into abandoning the use of our neighborhood common areas out of fear.