Network
Network security
Security has moved to the forefront of network management and implementation. The overall security challenge is to find a balance between two important requirements: the need to open networks to support evolving business opportunities, and the need to protect private, personal, and strategic business information.
The application of an effective security policy is the most important step that an organization can take to protect its network. It provides guidelines about the activities to be carried out and the resources to be used to secure an organization's network.
Layer 2 security is not discussed in this chapter. For information about Layer 2 LAN security measures, refer to the CCNA Exploration: LAN Switching and Wireless course.
Why is Network Security Important?
Computer networks have grown in both size and importance in a very short time. If the security of the network is compromised, there could be serious consequences, such as loss of privacy, theft of information, and even legal liability. To make the situation even more challenging, the types of potential threats to network security are always evolving.
As e-business and Internet applications continue to grow, finding the balance between being isolated and open is critical. In addition, the rise of mobile commerce and wireless networks demands that security solutions become seamlessly integrated, more transparent, and more flexible.
The Increasing Threat to Security
Over the years, network attack tools and methods have evolved. As shown in the figure, in 1985 an attacker had to have sophisticated computer, programming, and networking knowledge to make use of rudimentary tools and basic attacks. As time went on, and attackers' methods and tools improved, attackers no longer required the same level of sophisticated knowledge. This has effectively lowered the entry-level requirements for attackers. People who previously would not have participated in computer crime
Security has moved to the forefront of network management and implementation. The overall security challenge is to find a balance between two important requirements: the need to open networks to support evolving business opportunities, and the need to protect private, personal, and strategic business information.
The application of an effective security policy is the most important step that an organization can take to protect its network. It provides guidelines about the activities to be carried out and the resources to be used to secure an organization's network.
Layer 2 security is not discussed in this chapter. For information about Layer 2 LAN security measures, refer to the CCNA Exploration: LAN Switching and Wireless course.
Why is Network Security Important?
Computer networks have grown in both size and importance in a very short time. If the security of the network is compromised, there could be serious consequences, such as loss of privacy, theft of information, and even legal liability. To make the situation even more challenging, the types of potential threats to network security are always evolving.
As e-business and Internet applications continue to grow, finding the balance between being isolated and open is critical. In addition, the rise of mobile commerce and wireless networks demands that security solutions become seamlessly integrated, more transparent, and more flexible.
The Increasing Threat to Security
Over the years, network attack tools and methods have evolved. As shown in the figure, in 1985 an attacker had to have sophisticated computer, programming, and networking knowledge to make use of rudimentary tools and basic attacks. As time went on, and attackers' methods and tools improved, attackers no longer required the same level of sophisticated knowledge. This has effectively lowered the entry-level requirements for attackers. People who previously would not have participated in computer crime