CompTIA Security_ Deluxe Study Guide_ SY0-201 - Emmett Dulaney [89]
Much of the telecommunications system we use today is built on microwave technology. Microwave has the ability to carry enormous amounts of data, communicate line of sight, and use broad power ranges. Figure 3.27 illustrates a cell network in a metropolitan area. A typical cell network is capable of handling hundreds of calls simultaneously, and cell usage is growing at a fast rate worldwide.
FIGURE 3.26 RF communications between two ground stations
Many people use cell phones for data communications. Most users assume that cell connections are private when in fact they may not be. Communications on a cell network can be intercepted using off-the-shelf equipment. Analog cellular communications can be easily understood, whereas digital cellular service requires additional equipment to decode transmissions.
A relative newcomer on the microwave communications scene involves wireless networks. Some of the wireless networks allow pagers, PDAs, and internal or private networks. Wireless networks operate in the 2.5 to 5.0GHz spectrum. When implementing wireless networks, you would be wise to make sure you implement or install communications security devices or encryption technology to prevent the unauthorized disclosure of information in your network. Many of the newer devices include encryption protocols similar to IPSec.
FIGURE 3.27 Cellular network in a metropolitan area
Employing Removable Storage
Computer systems have become modular over the last few years, and one of the benefits is removable media. Removable storage (commonly known as removable media) refers to any type of storage device (such as a floppy drive, magnetic tape cartridge, or CD-ROM) that can be removed from the system. Disk drives that once cost thousands of dollars now cost hundreds or even less. What once took up a whole room can easily be put in a coat pocket.
It’s important to remember that removable media is subject to viruses, physical damage, and theft. If a CD-ROM is stepped on or scratched, it probably won’t work properly. If it’s stolen, it won’t be available, and the information it contained will be gone forever. That information could include customer lists, IP addresses, databases, financial spreadsheets, or anything else of a sensitive nature.
The following sections discuss the most common types of removable media in use today and the physical and operational measures necessary to safeguard them.
CD-R/DVD-R
The CD Recordable (CD-R) is a relatively new technology that allows CDs to be made or burned on a computer system. CD-Rs operate like regular CDs, and they can be burned quickly. Most new computer systems come standard with a CD-R burner or CD-R drive. You can quickly back up data to or restore data from the CD-R.
CD-Rs are susceptible to computer viruses, and an infected file on the computer that is transferred to the CD-R will infect another system when the file is downloaded. All files need to be scanned for viruses before being written to or read from a CD-R. Data theft is also easy with a CD-R; an attacker can get on a system that has a CD-R and copy data from hard disks or servers. Some older CD-Rs are susceptible to erasure by sustained exposure to sunlight, so it’s generally a good idea to keep CD-Rs out of environments that are high in ultraviolet (UV) light.
Whether the removable media you use is tape, CD-R, hard drives, or other media, you should bear in mind that one of the biggest vulnerabilities you face is the theft of that media and the data it holds. The best protection you have is to keep a close watch over the media; make sure it’s securely and safely locked up when not in use.
While the exam focuses on CD-R, you should