Biblio

Blockchain technology has made it possible to store and send digital currencies. Bitcoin wallets and marketplaces have made it easy for nontechnical users to use the protocol. Since its inception, the price of Bitcoin is going up and the number of nodes in the network has increased drastically. The increasing popularity of Bitcoin has made exchanges and individual nodes a target for an attack. Understanding the Bitcoin protocol better helps security engineers to harden the network and helps regular users secure their hot wallets. In this paper, Bitcoin protocol is presented with description of the mining process which secures transactions. In addition, the Bitcoin algorithms and their security are described with potential vulnerabilities in the protocol and potential exploits for attackers. Finally, we propose some security solutions to help mitigate attacks on Bitcoin exchanges and hot wallets.

When we setup a computer network, we need to know if an attacker can get into the system. We need to do a series of test that shows the vulnerabilities of the network setup. These series of tests are commonly known Penetration Test. The need for penetration testing was not well known before. This paper highlights how penetration started and how it became as popular as it has today. The internet played a big part into the push to getting the idea of penetration testing started. The styles of penetration testing can vary from physical to network or virtual based testing which either can be a benefit to how a company becomes more secure. This paper presents the steps of penetration testing that a company or organization needs to carry out, to find out their own security flaws.

Linux is used in a large variety of situations, from private homes on personal machines to businesses storing personal data on servers. This operating system is often seen as more secure than Windows or Mac OS X, but this does not mean that there are no security concerns to be had when running it. Attackers can crack simple passwords over a network, vulnerabilities can be exploited if firewalls do not close enough ports, and malware can be downloaded and run on a Linux system. In addition, sensitive information can be accessed through physical or network access if proper permissions are not set on the files or directories containing it. However, most of these attacks can be prevented by keeping a system up to date, maintaining a secure firewall, using an antivirus, making complex passwords, and setting strong file permissions. This paper presents a list of methods for securing a Linux system from both external and internal threats.