CompTIA’s Network+ certification Study Guide part 15 is a globally-recognized, vendor neutral exam that has helped over 235,000 IT professionals reach further and higher in their careers. The 2009 Network+ exam (N10-004) is a major update with more focus on security and wireless aspects of networking. Our new study guide has been updated accordingly with focus on network, systems, and WAN security and complete coverage of today’s wireless networking standards. | 126 CHAPTER 3 Network Devices NOTES FROM THE FIELD. Monitoring Traffic Through Firewalls As Internet access has become a more common fixture in organizations so has monitoring the Web sites visited by personnel in those organizations. Firewalls are used to prevent unauthorized access to the internal network from the Internet but also enable organizations to monitor what their employees are accessing on the Internet. Companies can check the firewall logs to determine what sites an employee visited how long they spent there what files they downloaded and other information that the employee may consider private. Companies may also stipulate the privacy of client information or those with a presence on the Web may include or create a separate policy that deals with the privacy of a visitor to their Web site. In terms of actual clients those people with whom a company does business the policy should state the level of privacy a client can expect. This may include the protection of client information including information on sales credit card numbers and so forth. In the case of police this might include information on a person s arrest record that can t be concealed under the Public Information Act and open records laws personal information and other data. For both clients and visitors to Web sites a company may stipulate whether information is sold to third parties that may send you advertisements spam or phone solicitations. Firewalls A firewall protects a secure internal network from a public insecure network. Firewalls are devices or software that has the ability to control the traffic that s sent from an external network such as the Internet to an internal network or local computer. As we ll see later in this chapter the features that are provided by a firewall will vary depending on the type you choose for your network. The most common implementation today is the use of a firewall between an organization s internal network and the Internet. Firewalls can be very .
