Firewalls A machine connected to the Internet that isn’t behind a firewall is a disaster waiting to happen. And you won’t have to wait long. A recent study by the Internet Storm Center has shown that unpatched Windows computers only lasted 20 minutes before they were infected by some malware. If you’re running Linux, you’re … Read more
An internet protocol version 6 (IPv6) is an identifier of a network interface that’s involved in an IPv6 computer network. If you don’t want to use Ipv6 addressing, you can opt to disable it either temporarily or permanently. Disabling IPv6 in CentOS First, check whether IPv6 is enabled on your CentOS 8 machine using the … Read more
SELinux or Security-Enhanced Linux is a mechanism or security module that provides access control security policies. In simple terms, it’s a feature or service used for restricting users to certain policies and rules set by the systems administrator. How to Temporarily Disable SELinux on CentOS Before you start disabling SELinux on CentOS , it’s prudent … Read more
PuTTY is a free and open-source cross-platform SSH and telnet client that even after being around for over 20 years remains one of the most popular SSH clients being used especially on the Windows platform. PuTTY is available to install from the default official repositories in most Linux distributions. For instance, you can install PuTTY … Read more
Skype is a popular software application currently developed by Microsoft that is mainly used for Instant Messaging and for Audio and Video calls and Video conferencing call. Among these functions, Skype can also be used for file sharing, screen sharing and text and voice messaging. In order to install Skype in your Linux distribution, first … Read more
Almost left half of the Internet users across the globe use ADSL routers/modems to connect to the Internet. However, most of them are unaware of the fact that it has a serious vulnerability in it which can easily be exploited by anyone with a basic knowledge of computer. In this post, I will show you how to hack an Ethernet … Read more
How to Add a New User in Linux To add/create a new user, all you’ve to follow the command ‘useradd‘ or ‘adduser‘ with ‘username’. The ‘username’ is a user login name, that is used by user to login into the system. [root@centos ~]# useradd centos When we add a new user in Linux with … Read more
Two dimensional arrays are also called table or matrix, two dimensional arrays have two subscripts Two dimensional array in which elements are stored column by column is called as column major matrix Two dimensional array in which elements are stored row by row is called as row major matrix First subscript denotes number of rows … Read more
Simplest data structure that makes use of computed address to locate its elements is the one-dimensional array or vector;number of memory locations is sequentially allocated to the vector. A vector size is fixed and therefore requires a fixed number of memory locations. Vector A with subscript lower bound of “one” is represented as below L0is … Read more
Worst Case Analysis In the worst case analysis, we calculate upper bound on running time of an algorithm. We must know the case that causes maximum number of operations to be executed. For Linear Search, the worst case happens when the element to be searched is not present in the array. When x is not … Read more