Out of my three dogs I think I can fairly well predict their given reactions.
If we are out and about during daylight and someone aproaches me and I am calm and friendly my two hounds will also be friendly and eager to love them to death.
Nico (11 yr old dominant intact 110 lb female Mostly Black and Tan coonhound/some great dane/some lab) has proven that if I am aproached at night when alone by someone who seems off she will not hesitate to advance and bark/growl and even try to bight a shoe. Nightime walks in the neighborhood or at the lake she is more alert than daytime but if I am relaxed about the person she is too.
She will also readily go after raccoons, and any other unknown wild critter that she feels might be a threat. Other dogs are fine and she will happily meet new dogs and play or hang out as long as it is not another dominant intact female, that is trouble waiting to happen and something I knowingly avoid.
She will bark at the doorbell and run to the door. Once the main door is open and she can see the person her reaction varies from total slathering excitement to alert mode depending on if she knows you. If we let somone in they are automatically friends and she loves them.
IF someone she doesnt know walks in without me opening the door or if Im not home..they arent too bright.
Loki, (2 1/2 yr old unnuetered black and tan/black mouth cur mix)...He is a complicated dog, not too bright and a typical hound in many ways, but also tough due to his breeding.
He demands order and routine or he becomes all sorts of unsettled. rearranging the furniture in the living room caused days of pacing and whining and unsureness. If there is a person or dog in his territory which includes the street he goes into full alarm mode either barking through the front window or running outside to do it through the fence if he is able.
If the gate to the kitchen is down this must be rectified god forbid one of the other dogs should be in the kitchen..that is a serious offense and must be solved. Cat stuck outside crying at the window..code blue!
But he is ridiculously submissive and gentle to everyone, is somewhat easily spooked and is overall the sweetest most gentle trustworthy dog with people I have ever met. He is also incredibly sensitive to being in trouble or even thinking he is in trouble.
I'm not sure the if the barking at people outside is excitement or resource guarding or both..either way it is obnoxious
He is protective though, if my husband and son are wrestling or tickling each other he will stand over my son..same with my husband and me, He will not try to protect my husband though as he sees him as Uber-Alpha.
If Nico and the pup get to playing overly rough he will stand in the middle and try to calm it down.
If my son or I is upset he does his best to fix it or at least stay nearby until all is well. I dropped hot lasagna all over my hand and the kitchen a few nights ago and got upset as well as burned, he did not leave my side for the rest of the night and kept trying to clean/groom/comfort my hand
So as sweet as he is, and as much as he ADORES other people he might well protect his pack if there was true danger, I would never count on it though.
The pup is shy, and has nipped once out of fear, he nipped the air though and it was an obvious deliberate miss and honestly well founded. He is a scrappy little thing though and not soft at all with us or the other dogs. Right now he is at the bottom of the pack but with age will most likely be the dominant of the three without much resistance as nico is getting older.
He would likely bite or attack out of fear if there was a confrontation to either our family or him, but given time and more socialization may end up being a very protective and reliable dog as he is deeply bonded to me.
So while I wouldnt depend on any of them to defend me in an emergency or attacker type situation they do offer me a lot of comfort and feelings of safety. Anyone who didnt know them well and came busting into our house would be an idiot. Anyone who was targeting houses for a break in would more than likely pass over ours simply because of them being here. Just as anyone thinking to attack or hurt me would surely think twice simply due to the two hounds size and intimidating looks and posturing.
Even if someone did decide to break in all of the jumping and slobber and chaos would likely make them think they were being attacked and would also knock them over