Copyright Goodheart-Willcox Co., Inc. 484 Networking Fundamentals System Backups System backups are necessary for recovering lost data. However, a common system backup will restore most data lost from an attack, but will not restore all the data. Any data saved during routine operation, which has not been backed up since the last incremental backup, will be lost. For example, assume a system is backed up every night at 7:00 p.m. Th e next day, the offi ce opens at 8:00 a.m. and begins business for the day. At 2:00 p.m., an intruder enters the system and formats the hard drive of the fi le server and then releases a virus on the workstations. All data stored since 8:00 a.m. is lost and cannot be recovered. 3.2 NET Tech Tip Network security is a rapidly growing field. It has its own special certification. The certification requires an intensive study of security far above the limited scope of this textbook. If you think you would like to become an expert in network security, visit the SANS organization website to find out more about the requirements. This certification is well respected and much in demand. CompTIA also offers a certification exam in cybersecurity: Security+. Figure 15-28 A packet sniffer provides a vast amount of information about a packet. Packet information Goodheart-Willcox Publisher Tech Tip The terms packet sniffer and protocol analyzer are commonly used interchangeably. A packet sniffer is mainly designed as a tool to capture packet contents and header information and to provide limited information. A protocol analyzer provides these same functions and much more, such as analyzing network traffic patterns, producing graphical representations of proto- col characteristics and the network infrastructure, and analyzing network problems.