<human>: I live on a cul de sac, and multiple dog owners on my street play with their dogs off leash in their front yards or even in the street.  

My 17 month GSD is only allowed off leash in my fenced in back yard.  When she sees the other dogs on our street, be it when I'm walking her on leash or from the car, she starts barking and lunging.  She typically ignores other dogs, or at least just looks and sniffs the air, when we're in other places.

I'm guessing this is territorial behavior?  Or protection mode?  I'd really like to walk her down the street--or even outside the front door--without any issues, and I don't think the other owners are going to stop letting their dogs off leash, as much as I'd like them to, so any training tips?  We currently do back aways and getting her to focus on me, but that only works when the other dog doesn't zoom up on us, like one did yesterday.  At least they both went into play bows, but when the other dog started running, my dog wanted to run after it and couldn't, very frustrating for both of us.

Summarize the given text in a few sentences.
<bot>: Another "how do I handle unleashed dogs playing in my neighborhood and coming up to me and my leashed dog" post/rant.