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Linux Security Basics

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Linux Security Basics

Security is always at the top of the list when setting up a network and also administering a network. Linux is an operating system that can be easily obtained over the internet due to its open source distributions. Linux is one of the most secure operating systems because of having less use than Windows for the end user. There are several security technologies in Linux that can be implemented into a network. The three technologies that I will be discussing are SELinux, chroot jail, and iptables. SELinux was developed by the National Security Administration in an effort to incorporate a strong, flexible mandatory access control architecture into the major subsystems of the Linux kernel. The NSA recognized that operating system security is critical at higher levels. It provides a tool to enforce the separation of information based on the confidentiality and integrity requirements. This helps when addressing threats of tampering and bypassing of application security. It also assists in the isolation of damage that is caused by malicious software or damaged applications. SELinux uses the Flux Advanced Security Kernel which contains components that provide support for enforcing many kinds of MAC policies like type enforcement, role-based access control, and multilevel security. The Linux kernel that is implementing SELinux enforces MAC policies that limit the user programs and system servers to only what they need to complete the job. When a limit is set like this it reduces or prevents the damage that the programs can do when they are misconfigured or compromised. Confinement in this way has no recognition of the root user. When SELinux is implemented in this way the security depends on the correctness of the kernel and the security policies. If a problem arises with the configuration of an application it is limited to the user...

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