# Implementation of a Lossless Moving Target Defense Mechanism
## 8 Conclusions and Future Works  
Our civilization's dependence on IT solutions, as well as the geopolitical situation, requires new research tasks and the delivery of new solutions in the field of cybersecurity. This article proposed a new approach to one of the MTD technologies using IP address mutation. We used an SDN and programming in the P4 language, which adds a new dimension to shaping the functionality of the data plane. In research on the effectiveness of MTD mechanisms, studies have rarely been conducted on the impact of the applied techniques on the quality of services provided to users [62]. The use of MTD techniques can lead to disruptions in service availability [7; 8] or, as is the case with IP address mutation mechanisms that utilize DHCP or DNS services, to connection interruptions [9]. The presented solution is distinguished from other proposed solutions by its ability to maintain the continuity of services. By applying the described solution, any interruption in TCP connections is avoided, which is significant for networks operating at bandwidths above 10 Gbps. The inability to transmit data even for a few seconds can result in significant data loss. Another important advantage of the proposed solution is its flexibility. This solution does not require modifications to the operation of services such as DHCP or DNS and thus is not limited by their functioning.  
Performance analysis of the proposed solution indicated that with an increasing number of hosts in the network, the permissible speed of IP address mutation drastically decreases. This is due to the use of an extremely simple mutation algorithm, in which IP addresses were mutated in a completely random manner at each step, necessitating the modification of entire flow tables. Such an algorithm is not optimal. In further work, researchers can attempt to optimize the mutation algorithm, in which IP addresses will be changed only for a portion of the hosts in subsequent mutations. Another scenario to consider is mutating addresses only for devices providing critical services. Considering the flexibility of implementation provided by the P4 language, further studies can introduce additional mutation scenarios.  
Another direction for future research involves conducting a detailed analysis of the proposed solution. The Mininet environment used in this study only allowed for the confirmation of the proposed solution's functionality. Since preparing a sufficiently large research environment, where programmable SDN switches would be utilized, is an extremely difficult and costly endeavor, there is a plan to develop an appropriate simulator in the OMNET++ environment.  
M.Z., M.M. and P.Z.: conceptualization, validation, writing--review and editing; M.Z.: data curation, formal analysis, investigation, methodology, resources, software, visualization, and writing--original draft; P.Z.: funding acquisition, project administration, supervision. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Polish Ministry of Science and Higher Education (No. 0313/SBAD/1310).  
Not applicable.  
Data Availability Statement: Data are contained within the article.  
The authors declare no conflicts of interest.  
The following abbreviations are used in this manuscript:  
API Application Programming Interface  
APT Advanced Persistent Threat  
ASIC Application-Specific Integrated Circuit  
BGP Border Gateway Protocol  
BMy2 Behavioral Model v.2