Does The Dog Dial "911?"

Many lame reasons people have for deciding against an alarm system are entertaining and not well thought out.  Here is one such excuse.  As the title indicates, there are people who rely on man's best friend for home protection.  I will agree that some breeds of dogs lend themselves well to deterring break-ins; the German Shepherd, the Rotty and various Bulldog breeds are in the mix.  I will also admit that a yappy dog, that barks it's yappy head off at anything that moves can serve as an alert mechanism, should some one be home to hear it.  Even then the animal is more  likely to be silenced without a second thought than actually cause a person to investigate the possiblity that their privacy has been invaded. 
The most likely scenario where a dog is expected to protect a home from intrusion and burglary is that the unfortunate gate keeper becomes the first victim of the crime.  People who don't respect your property or your privacy are not likely to respect your pet, either.  The best that can be hoped is that the intruder merely provides the animal with a distraction such as a dog treat or piece of meat.  They might even make a friend.
Even some dogs that are very protective of their owner and their family, may not care to protect a giant plastic soda bottle full of change, or cameras, jewelry, guns, baseball card collection, grandmother's hand-knitted afghan or even the food in the refrigerator, which dogs like very much.
During such an event, the dog will have difficulty notifying the homeowner while they are away at work.  Most dogs don't know how to dial "911," and if they do, their report would be vague...dare I say "ruff."  After such an event, the descriptions dogs give to investigators is sketchy, at best.  They find it difficult to express just what the intruder smelled like, or what they said.  On the bright side, dogs are color blind and less likely to profile intruders based on any stereotype.
This is all stated before advanced fire notification is mentioned: or carbon monoxide, flood, etc. 
One item you should take into account as you protect your home and family with a proper alarm system is to make sure the monitoring center knows that you have pets in the home.  Have the facility note the likely location of your animals during the day (if you know).  The police, responding to a burglar alarm will want to avoid any misunderstandings on the part of your pet, especially if it is the man-eater you think it is, like a Pit-Bull or a Chijuajua.  The fire department may also be able to rescue a trapped pet if they know where it hangs out in the house, and if doing so won't be too risky for a fire-fighter.