Security

The network infrastructure, services, and the data contained on network-attached devices are crucial personal and business assets. There are two types of network security concerns that must be addressed: network infrastructure security and information security.
Securing a network infrastructure includes the physical securing of devices that provide network connectivity, and preventing unauthorized access to the management software that resides on them, as shown in Figure 1.
Information security refers to protecting the information contained within the packets being transmitted over the network and the information stored on network attached devices. In order to achieve the goals of network security, there are three primary requirements, as shown in Figure 2:

• Confidentiality - Data confidentiality means that only the intended and authorized recipients can access and read data.

• Integrity - Data integrity means having the assurance that the information has not been altered in transmission, from origin to destination.

• Availability - Data availability means having the assurance of timely and reliable access to data services for authorized users.

To learn more about security as a requirement for reliable networks, refer to the Appendix for this chapter.

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