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Encryption Ensuring Safe Shopping

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Chapter 8

8.3.4 Security Tokens

Encryption protects the contents of your messages and files. Hashing, digital signa- tures, and digital certificates authenticate the people and places that you’re doing
business with.
Security tokens
authenticate YOU. You’re probably thinking, “But I do that myself when I enter my private pass-
word.” True. The problem is that passwords can be easily cracked and stolen by hackers. Security tokens provide a much stronger two-factor authentication that
includes both data often a password and a physical device.
Two-factor authentication is something that you already use all the time offline. When you use an ATM card to withdraw money from your bank account, you’re
using two-factor authentication. The physical ATM card identifies you factor one, as does the PIN number that you enter factor two. While it’s important that you
don’t misplace either, neither is really useful without the other. A criminal can play with your ATM card all day, but he’s not getting money from your bank unless he
also knows your PIN number.
Security token A two-factor authentication method using a physical device as well as a secret code.
An ATM card is only one example of a security token. Other forms of security tokens are physical tokens a small hardware device, smart cards, and biometric
systems. With biometrics, the physical component is biological data like a finger- print or retinal scan.
Chapter 9
Browsers Bite Back
Chapter 9
Browsers Bite Back
Mike spent a lot of time surfing PC gaming sites on the Internet. Still, he was a little put back one day when visiting an old gaming site he hadn’t been to in five or six months.
Just connecting to the site, without logging in or providing any information, he was greeted as a welcomed old friend:
Welcome Back Mike of Bendersville While the goal was to bring Mike figura-
tively back into the fold, the effect was to actually creep him out.
Mike wanted to know exactly how the gaming site knew
who he was. He began to wonder if he’d fallen
victim to that spy- ware he’d been
hearing so much about…
Chapter 9
While it’s possible that Mike had fallen victim to spyware, the link to those details that creeped him out was probably stored on his own computer, sitting in plain
sight in his Cookies folder. Allowing cookies to track your activities is only one of several ways that your Internet browser can bite back.
In this chapter, you’ll learn what it is that cookies do and how to rein them in to ensure that they only work FOR you and not against you. You’ll also learn about
browser options and how you can set them to increase your safety and security.

9.1 Making Cookies Work FOR You

Contrary to popular belief, a cookie is not a program. It doesn’t DO anything per se. It’s simply information passed to your web browser when you visit a web-
site that uniquely identifies you and your system. Cookies land on your computer almost continuously as you surf the Internet. Those
are then passed back to websites every time you re-visit them. Websites use your cookies to recall infor-
mation about your previous visits, to determine if you are currently logged into the site, to change some aspect of the site, to provide additional functionality for
the site, or to record detailed data about your visit. Accepting cookies is part and parcel of using most websites. Some websites will not work correctly if you do not
accept the cookies they provide.
Cookie Information written to your hard drive by a website that you visit. A website can use a cookie to recognize you, and sometimes remember custom settings, when you visit
that site again in the future.
In general terms, a cookie is a small piece of information that consists of a single item—a namevalue pair. In most cases, the “name” is a conglomeration of the
website name and the user ID you’ve selected or been assigned for the site you’re visiting. The “value” is a unique numeric value that the site has assigned to that
name. Together, the namevalue pair uniquely identifies you every time that you visit that website from the same computer.

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