A user runs an IRC client that is connected to a server on the IRC network. The IRC is a client-server, multiuser, and multichannel chatting application that facilitates users to communicate with their peers in real time on the Internet worldwide. One of the important services used in the smart phones is instant messaging (IM) applications that follow customized versions of the Internet Relay Chat (IRC) protocol. When a security service is proposed to counter a particular type of breach, in short period of time, a new attacking mechanism is invented by malicious user(s). They have become an ideal hub for malware, grayware, and spyware developers who can easily exploit the vulnerabilities and insecure communication channels. They have also become the target of hackers and crackers for carrying out malicious activities. People are using smartphones for social networking, online banking and shopping, web browsing, tracking locations such as hotels, restaurants, and hospitals, and mail checking, besides the conventional uses including phone calls and messaging services. Smartphones have various types of connectivity options such as WiFi, Bluetooth, LTE, and ubiquitous computing features, which make them an important part of our daily lives. The analysis will help the security experts to propose appropriate countermeasures to reduce the attackers’ utility, thereby making it less attractive for those attackers to launch the attack. We use a game theoretic model to analyze the feasibility of DDoS attacks on the IRC platform, keeping in view the attacker’s objective. In this paper, we demonstrate the effect of DDoS attack on the performance of an IRC server using a test bed. Professionals working in the domain of cyber security are challenged by the devastating effects of distributed denial of service (DDoS) attacks on all major platforms including Apple Macintosh, Windows, Unix, and Linux. However, these messengers face many cyber security threats and the required security features are either not available at all or are insufficient for efficiently countering the threats. Customers of the formerly mentioned messengers are estimated in millions because of the attractive features offered by them. Finally, direction for future research work has been pointed out.Latest technologies of voice over IP (VoIP) and mobile messaging for smartphones messengers such as WhatsApp, Viber, Skype, etc., offer free-of-charge facilities of worldwide SMS, MMS, and voice calls to their users, unlike the traditional and expensive cellular or telephone networks’ services. This survey paper deals with the introduction of DDoS attacks, DDoS attack history and incidents, DDoS attack strategy, DDoS attack tools, and classification of various attack and defense mechanisms. All these tools could launch DDoS attacks from thousands of compromised host and take down virtually any connection, any network on the Internet by just a few command keystrokes. Since then several DDoS attack tools such as Trinoo, Shaft, Tribe flood network (TFN), Tribe flood network 2000 (TFN2K) and Stacheldraht are identified and analyzed. DDoS mainly started in 1998 but the influence of it was realized by the people only when the big organizations and corporations were hit by DDoS attacks in July 1999. Communications in Computer and Information Scienceĭistributed Denial-of-service (DDoS) attack is one of the most dangerous threats that could cause devastating effects on the Internet.