# A Systematic Literature Review on Penetration Testing in Networks: Future Research Directions
## 3 Literature Review
### Detecting Open Ports and Possible Attacks
It illustrated the type of penetration test, namely social engineering test, web application test, physical penetration test, network services test, client-side test, remote dial-up war dial, and wireless security test. It also presented the process of penetration testing and the criteria for selecting the best open source tools such as Nmap, Metasploit, Wireshar, OpenSSL, Cain and Abel, THC Hydra, and w3 af to improve the security of the infrastructure. The study provided a diagram of the input testing procedure and the devices used. [PERSON] and [PERSON] [22] focused on how SMEs can overcome the difficulties and enormous costs associated with testing networks in Rwanda. The study discussed the problems faced by SMEs such as the lack of network security experts and unknown network assets. The study suggested the use of user-friendly network security tools such as Nessus, Qualys, Nmap, and LAC Falcon. The proposed solution, SMEsec, included a sensor consisting of tools such as Nmap and a DoS attack simulator, database, filter, web portal, and a team of network security experts. SMEsec performed various tasks such as asset discovery, asset registry creation, vulnerability identification, and simulation of DoS attacks against the web server. The results showed that it is possible to improve SMEsec's network security status. [PERSON] et al. [23] tested the vulnerability of an Amazon Echo to a denial-of-service (DoS) attack. In this study, one instance of Kali Linux was used to perform the attacks on the device, while another instance of Kali was used to monitor the network during the attack. In this study, information was collected using the Nmap scan and the SPARTA tool in Kali Linux to obtain information about the open TCP ports on the device. Then, network traffic was analyzed using Wireshark to show where network packets were lost during the attack. This study revealed that it can be quite easy for an attacker with the knowledge and ability to gain access to a home network to obtain information about the connected devices using free and relatively simple penetration tools in Kali Linux. In the future, authors will perform more invasive penetration techniques. [PERSON] and [PERSON] [24] targeted TCP network traffic to detect the slow port scanning attacks. The study proposed an approach to detect slow port scanning attacks not only over a static time interval, but also over all attacks that occur with a gradual increase or decrease in time duration. The proposed approach contained four modules: data acquisition, packet detection, scanning filter, and detection filter. The approach detected attacks using live data. It classified the single and parallel port scans based on the attempts made. This achieved discrimination between the faster and slower scans. This solution can be used to detect automatically scanning worms on the internet. [PERSON] et al. [25] discussed the analysis of network vulnerabilities in brain signal processing, which is important in healthcare. The study discussed that network device components, such as switches and routers, are vulnerable to various types of attacks such as viruses, worms, DoS, and Trojans. In addition, the attackers can inject malware or send their segments through IP spoofing and TCP session theft. The authors used different scanning techniques, such as ping sweep, TCP sweep, and null sweep, for the popular brain signal databases using Wireshark and Nmap tools. They found the ping sweep support status, TCP sweep times, and null scan times on different servers. [PERSON] and [PERSON] [26] proposed to perform MikroTik router vulnerability testing for a network vulnerability evaluation with the penetration testing method. Their goal was to prevent possible threats such as DDoS attacks and brute force. They mentioned that DoS attacks were very common in 2021. The method used in this research is an experimental method. Thus, brute force and DDoS penetration tests were performed directly on the object. The tools used were Nmap for scanning and Routerploit.