ccna 9.4.1.2

ccna 9.4.1.2.The purpose of protecting the network is to ensure that applications, processes, and users can reliably and securely operate with each other using shared network resources. Because the shared network infrastructure carries voice and data, the security of the network infrastructure and access to it is critical to protecting voice functions. Because Voice over IP systems are installed on data networks, they are also known as potential targets for hackers, the176 Chapter 6 Protecting the LAN Whereas before, hackers targeted only PCs, servers, and data applications. Hackers find weaknesses in Voice over IP systems through the open and well-known standards and protocols used in IP networks. EavesdroppingEavesdropping is the unauthorized interception of voice packets or RTP media streams. Eavesdropping obtains exposed confidential and private information by intercepting and reconfiguring packets in the voice stream. Hackers can use a variety of tools to eavesdrop.DoS Attacks A DoS attack is defined as a malicious attack or a call processing device that denies access to a legitimate user's service because of overload. Most DoS attacks fall into one of the three categories listed below.Network resource overload - This refers to an overload of network resources that are required for a service to function properly. The most common network resource is bandwidth. A DoS attack uses all available bandwidth, causing authorized users to be unable to access the required services.Host resource scarcity - Leaving critical host resources depleted. When these resources are maximized by a DoS attack, the server stops responding to legitimate service requests.Out-of-bounds attack - Refers to the use of illegal packet structures and undesired data that causes the remote . system's operating system to crash. This type of attack . An example is the use of a combination of TCP flags from North Law. Most TCP/IP protocol stacks are developed to respond to normal usage; they do not take into account abnormal behavior. When a protocol stack receives anomalous data, it may not know what to do with the packets, resulting in a system amputation crash.6.4.4.4 VoIP SpamVoIP spam, or SPIT (SpamoverInternetTelephony), is the unsolicited and useless batch of low messages broadcast over VoIP to end users on the enterprise network. In addition to being annoying, high-volume calls can significantly impact endpoint availability and productivity. Because bulk calls are difficult to track, they can be used for fraud, unauthorized use, and privacy violations.SPIT has the potential to become a major problem. SPITs can be generated in a manner similar to spam, and they are used by botnets to launch attacks on millions of VoIP users from compromised hosts. Unsolicited commercial spam and malicious emails make up the majority of emails worldwide. There is a fear that VoIP will suffer the same fate as email.