Hello- new to yorkie talk here!

So glad to find these forums because I have a big problem. I am absolutely in love with my 2 year old yorkie-mix, Wally(he 1/2 poodle in him but looks/acts very much like a yorkie) but he is VERY over-protective of me. I am at the breaking point now because last night he bit a friend of mine (that he wasn't familiar with) HARD on the leg as I was letting him in the house

. Wally is just about the friendliest dog to people he knows well (family and close friends), but to strangers he is absolutely a terror

. Barking and attack mode-it is very hard to control him when he gets like that. He doesn't like people or kids that he doesn't know. I am afraid to let kids even get near him!!! It is too bad because he really is an amazing dog to people that he knows. Note- he is totally fine with other dogs.
What do i do?

this isn't the first time he bit. he tried to get a jogger once and also a male neighbor that approached me that he didn't know. he has been to obedience class and does fine in that setting but as soon as we are back home/in the neighborhood his possessiveness returns. He is extremely smart and knows about 10 tricks so I know he can learn but I think I haven't found the right way to deal with it. I have had him since 8 wks old and he has never had bad experiences with people. sooo lost, confused, angry at my dog


