# HSM4 SSL: Leveraging HSMs for Enhanced Intra-Domain Security +
## 1 Introduction  
In an era defined by rapid technological advancement and increasing digitization, security and privacy have emerged as paramount concerns for individuals, businesses, and organizations worldwide. The seamless exchange of sensitive information across networks and the internet has necessitated the development of robust mechanisms to protect data integrity, confidentiality, and authenticity. Consequently, a great deal of work has gone into making internet communication channels secure. However, as the digital landscape evolves and networks expand to encompass a multitude of devices, a new dimension ofsecurity challenges arises. This is particularly evident in intra-domain environments, where organizations face a growing need to secure communication within their own networks. In an intra-domain environment, all communications are confined within the parameters of a single _autonomous system_ (AS). This term refers to a collection of interconnected physical network components, such as servers, data centers, and other network devices, that are administered and overseen by one organizational domain. Such an environment is characterized by the internal exchange of information and services, like email and web browsing, without extending beyond the organization's network boundaries to other domains [1]. Expanding the network capacity within a domain to accommodate numerous devices with networking capabilities underscores the importance of enhancing security measures in these settings. Notably, in 2020, insider employees, frequently using compromised devices, were responsible for 68% of organizations' security incidents and malicious activities [2]. This highlights the critical need to focus on security issues not just in the public internet but also within internal networks. Moreover, organizations that manage a multitude of servers to manage multiple requests commonly deploy _load balancers_ or _reverse proxies_ to intercept traffic originating from multiple hosts or endpoints. These tools effectively sort out incoming requests and distribute them among the back-end servers. The significance of the load balancing process extends across all cloud environments, offering reliability and availability through continuous monitoring of server statuses and directing requests exclusively to servers that are available [3]. Furthermore, it alleviates the workload on back-end servers by avoiding the need for decrypting traffic, achieved through the utilization of _Secure Socket Layer (SSL) termination_. SSL termination not only assists in intrusion detection by identifying anomaly packets but also ensures that these packets are detected before reaching the servers [4]. Despite these advantages, it is important to note that this approach introduces security vulnerabilities by establishing insecure channels between the reverse proxy and the back-end servers, exposing communication to various potential attacks. Furthermore, since 2016, the Certificate Authority (CA)/Browser Forum, responsible for setting standards in the issuance and management of SSL certificates, has ceased issuing SSL certificates for servers with private IP addresses [5]. Plus, following the CA/Browser Forum meeting in March 2023, Google declared its intention to limit SSL certificate validity to 90 days instead of 398 days. Managing SSL certificates with a 90-day validity period not only adds complications to the management of certificates, particularly in scenarios where organizations operate many servers, but it also introduces increased costs associated with frequent renewals and administrative overhead [6]. With these aforementioned issues, along with our previous work's observations [7], both academia and implemented systems are currently inadequate in representing the progress in secure intra-domain communication. The reasons for this underrepresentation remain obscure. Consequently, this situation is consistently leading to numerous security breaches and attacks within organizations.