A Methodological Approach to Evaluate Security Requirements Engineering Methodologies: Application to the IREHDO2 Project Context  
[PERSON]  
1 IRTI/Universite Paul Sabatier, 31062 Toulouse, France; [EMAIL_ADDRESS] (S.T.B. ); [EMAIL_ADDRESS] (A.S.W. ); [EMAIL_ADDRESS] (A.O. ); [PERSON]B.) 2 Sopra Seta-IZS, 31772 Colomerys, France  
3 Cart Department, College of Technological Innovation, Zayed University,  
Abu Dabi 4783, United Arab Emirates  
4 Correspondence: [PERSON]]  
[1 IRTI/Universite Paul Sabatier, 31062 Toulouse, France; [EMAIL_ADDRESS]o.in (S.T.B. instance, adding a DMZ (de-militarized zone) into an existing network provides a perimeter defense by isolating the internal network devices that are accessible from the public network. Nevertheless, the DMZ significantly alters the network architecture. In this regard, considering network security too late in the network development cycle (i.e., post deployment of network designs) would render additional costs and complexity in terms of incorporating any changes to the existing infrastructures. The difference in the return of security investments considered at early or at late stages of the system development cycle can range from 12 to 21 percent [10]. Therefore, it is necessary to examine network security at earlier stages, i.e., right from the planning stages of networks architecting. This perspective is known as security-by-design, which enforces the consideration of security right from the requirements analysis. Therefore, network security requirements play a critical role since they impact the decisions related to the implementation of security controls [2]. Indeed, bad network security requirements can lead to ineffective and costly security or worth security holes in the network security design. An effective network security requirement engineering is needed to help organizations in capturing cost-effective security solutions that protect their networks against malicious attacks while meeting the business requirements. Requirements Engineering (RE), in general, is a sub-discipline of system/software engineering, which subsumes the activities of gathering (a.k.a. eliciting), evaluating and documenting system/software requirements. Security requirements engineering (SRE) methods extend RE to the security context, by enabling the integration of risk analysis concepts. They help organizations in capturing security requirements by analyzing the business risk impact of potential threats. However, the diversity of SRE methodologies leads security requirements engineers to an open question: How to choose one? Utilization of various procedures and tools, choosing unsuitable RE instruments or utilization of inadequate techniques for eliciting requirements are among the most frequently reported issues [11]. Several comparative studies on SRE methodologies are available. Nonetheless, their evaluation is often based on a set of ad hoc criteria, hence these comparison criteria may not fit the SRE needs of every company. Thus, a systematic method must be proposed to properly capture the actual company's needs regarding an SRE methodology. In this article, we address this issue by proposing a requirements engineering-based evaluation methodology. It helps in characterizing the appropriateness of a SRE methodology by capturing the SRE needs of the stakeholders as well as the quality characteristics of good security requirements (a.k.a. quality criteria). We developed this evaluation methodology during the IREHDO2 project where we could interview security experts involved at each step of the security process. In this project, security experts of an aircraft company wanted to improve their security process in order to increase the assurance on the final security solution enforced on their aircraft networks. More precisely, they were interested in enhancing their security requirement practices. This group of security experts included security requirement engineers, risks analysts as well as security testing experts who are involved at different levels of the security process.