Mythic Monday – The Lion, the Mouse, and the Fox
In case you haven’t figured it out, I fall back to blogging about an Aesop fable when I’m stuck for other things. In this case, I am stuck underneath a cat and all of my mythological references are about half a meter out of reach. Luckily, many of Aesop’s fables are available online. Like, for example, this one.
In this story, a sleeping lion is startled awake when a mouse runs across his nose. Looking all around for whatever woke him up, he checks all over his cave and finds nothing. A fox observes this behavior and, knowing that he can outrun a sleepy lion, makes fun of him for being afraid of a mouse. Attempting to safe face, the lion claims not to have been afraid, but more affronted by the bad manners.
As usual, Aesop completely missed the point of his story. Instead of being a droll observation of class structure of ancient Greece, it’s obviously a better lesson for dealing with initial network probes. Probes are a fact of life on the Internet. All sorts of attackers on the Internet want to take over your systems. The first step is to send out a small probe and uncover various things about the potential targets. This is part of what firewalls are supposed to prevent.
A lion needs a few things as it sleeps. Air, probably being the most important. However, if it wishes to stay asleep, it helps to have a way to keep the mice out of the lion cave.
As an aside, I personally question how common it was for lions to sleep in caves. Modern lions don’t seem to do this… though perhaps that has less to do with lion slumber preferences and more to do with a general lack of caves in subSaharan Africa.
So, if you have a lion that wish to keep vermin-free, it would help to put up some sort of chicken wire fence over the “cave”, thereby allowing in air and preventing mice (and rats… it’s a twofer!). In much the same way a firewall keeps out known malicious traffic so your servers can crunch their numbers in piece. Admittedly, our firewalls block worms. Worms are smaller and trickier than mice, which is why the firewalls are more complex and expensive than chicken wire.
Running without a firewall would be like trying to coax a lion into sleeping while they are being trampled flat by a veritable cascade of members of the family Muridae.