You will usually encounter the Cerberus in pairs. They are fast and move in very random patterns. Tha handgun is a sufficient defense, with the shotgun being more capable of handling multiple Cerberus attackers. They tend to burst through windows often, so be ready when walking down quiet hallways with many windows.
The main things the dogs do is run up towards you and do a jumping bite. While these are predictable because they are the only attack they do and can be seen coming a mile away, if their about to jump there is little you can do to avoid it. If your about dead and a dog jumps to bite you they'll knock your character down and lock their jaws around your neck.
Using the handgun can be great at close range. By coming close to a downed dog and shooting downwards at it each time it tries to stand back up, you can kill it with no problems. This works even better if you can corner it. This however is difficult if there is more than one dog around to kill as you'll probably be attacked from behind also. If this happens you should use a distant stance and pick them off.
Using the shotgun while the dogs are in the air will knock them down and should kill them in one shot. The problem with this tactic is that there can be some trouble with the timing and, depending on the title, the games collision detection. Still its a good thing to know if your low on ammo.