CHAPTER 2
Why use cryptography?
There are several reasons why you should always use cryptography on your personal and professional communications, they all come down to your privacy and security. Below we list 7 points so you can better understand the importance of this technology.
Email is one of the most insecure systems ever simply because it was not designed to be secure. Messages travel through many machines, networks and even countries, and they can be intercepted in many different ways by anyone who has access to them. By default their contents (text, images and attachments) are transmitted without any security at all.
Email providers (such as Hotmail, Gmail, Yahoo) store all your sent and received messages for indeterminate time – possibly forever – even after you have erased them from the trash bin or terminated your account. They do it for two reasons: to sell you more services and advertisements, and to collaborate with government surveillance programs.
The registers of your email communications may be – and often are – stored in machines located in countries different than yours, and once they are in another jurisdiction they are subjected to that nation's laws and there is virtually nothing you can do to claim the right to privacy you may have in your country.
This may happen even if you haver never been in those countries.
Cryptography can be used at home or in business and it works with a wide variety of devices such as personal computers, mobile phones, tablet computers, workstations, servers, complex network infrastructures and others.
It can be used for personal communications with family and friends, to store sensitive information, to backup sensitive information, to encrypt the whole disk, to send and receive files, to provide a secure channel to access one's machine, among other uses.
When you offer a secure means for people to communicate with you it demonstrates how much you value and worry about their privacy and security. This is especially true in business where there is often a high volume of sensitive information being exchanged, but it also applies to personal relationships.
To send and receive encrypted messages requires that others you communicate with also use cryptography, so if you start using it you will naturally tell other people about it. Given the advantages and benefits of using cryptography, many of them will eventually embrace it, and it is easier to start doing something when others they know are already doing.
Another advantage is that it is possible to use cryptography and still communicate with people who don't use it. The communication will be unencrypted of course, but at least you don't have to limit yourself to only one group of people.
There are many types of cryptography systems for different needs with varying prices. The system we present to you in this book, GnuPG, is 100% free both in terms of price and in freedom to use it. You can set it up in any environment you want without having to pay for licenses, royalties, fees or require any type of authorization, and the program is powerful enough to be used in a single computer and in the infrastructure of a multinational corporation.
Last but not least, your email communications are private and they should remain private. It doesn't matter if you send a message telling about a new restaurant in the city, your credit card number with the password (yes, people do it), or a picture of yourself naked (yes, people do it A LOT), it is not of anyone else's business and it is up to you to ensure your privacy remains private.