CompTIA A+® Certification All-In-One For Dummies®, 2nd Edition

1.4. Methods of Securing Transmissions

After you authenticate users and authorize them to access certain parts of the network, you should then consider methods of securing information while it travels along the network cable.

Most network communication is sent along the network wire in cleartext, meaning that anyone connected to your network can read the information. But if the information is traveling across the Internet, anyone can view that information if it is passed in cleartext.

Most Internet protocols, such as HTTP, send information in cleartext, and it is up to the people who set up the servers that use these Internet protocols to encrypt the information before it is released to the Internet. Encrypting the information means that the information is run through a mathematical calculation that generates an altered version of the information: a result. For example, the words Glen Clarke could be encrypted to look like 7y3i s3fk4r. If anyone intercepts such encrypted information and views it while it is traveling across the wire, the information would mean nothing.

Here is a real-world example. You type your credit card number on a Web site, but you certainly do not want that credit card number to be viewed while you send it from your client computer to the server. You want to be sure that the Web site where you enter the credit card number encrypts the traffic. You can tell by the lock icon that appears in the Web browser, as shown in Figure 1-9.

Figure 1.9. Identifying ...