A Brief History of Cybercrime and Cyberwarfare - The Technical and Social History of Software Engineering - page 397

Piggybacking on unsecured networks is fairly common and probably the least
troubling kind of theft. However, it is not a victimless crime. The hijacked network
fees will probably go up, based on the bandwidth and amount of material down-
loaded, so the true network owner will lose money.
Piggybacking is easy to do. If a network is unsecured and shows up on a com-
puter list of available networks, it is only necessary to click “connect” and it can
be used.
There are also commercial sniffers that will report the brands of local wireless
routers within range. Once the brand is identified, the hacker can then download
data from the manufacturer's website that gives the original password for the
brand and model of router. With this information in hand, the hacker can then use
the wireless network more or less at will.
Free public wireless hotspots are in daily use by hundreds of students from a
nearby university, as well as by local citizens who happen to use computers, iPads,
Kindles, and other wireless devices in the vicinity. Free wireless networks are a
great convenience but are also fraught with danger of losing passwords, credit card
numbers, and other forms of personal information.
How does this happen? One method is that skilled hackers can tap into the
network and extract information from any or all users by using the router ID, as
already described. A second method is that a hacker can construct a phony wire-
less hotspot with the same name as the ones used by coffeeshops or local restaur-
ants.
When using public networks, be sure to specify “public network” when your
computer asks about what kind of network it is. It is also best to do only casual
browsing and avoid things like online purchases with credit cards or online bank-
ing. Of course, the most common use of a computer today is probably email or
messaging, so there is a high probability of compromising the email addresses of
both senders and recipients.
Denial of Service Attacks
Computers and servers are fast and can handle thousands of transactions per
minute, but they all have a finite capacity that can be exceeded. This is why we
sometimes have waits when we attempt to reach a website or perform a task.
The idea behind denial of service attacks is to saturate a computer or a server
by sending millions of messages that require some form of processing and thereby