# LSSDNF: A Lightweight Secure Software Defined Network Framework for Future Internet in 5G-6G
## 3 Proposed Approach
Jitter is the effect we experience when there is a delay in data transfer in a network. For a network to be good, the jitter should be as low as possible. ### Single-Controller TCP SDN vs. Multi Controller TCP SDN

In this part, we contrast a topology with just one SDN controller with one with several (in this case, three) SDN controllers. This topology has 34 network devices, including 23 computers, 8 OpenFlow switches, and 3 SDN controllers. The single-controller topology has 32 network devices in total, including 23 computers, 8 OpenFlow switches, and one SDN controller. We tested both networks for 180 s while setting the bandwidth to 26.2 Mbps and using TCP protocol packets. The network characteristics are displayed next in Figures 12-16. Figure 11: Jitter variation in SDN. Figure 10: Jitter variation in Traditional Network. Figure 12 shows that both networks' bandwidth fluctuates in a manner that is essentially the same, with no topology experiencing more significant fluctuations than the others. Figure 13 shows that both topologies' data transfer rates are similar and that the multi-controller architecture performs somewhat better than the single-controller topology. Figure 2:0 Bandwidth Fluctuation TCP single-controller SDN vs. TCP Multi-controller SDN. Figure 2:1 Transfer Rate/Throughput of TCP single-controller SDN vs. TCP Multi-controller SDN. Figure 2:2 UDP bandwidth fluctuation of single-controller SDN vs. Multi-controller SDN. Figure 2:3 Transfer rate/Throughput of the UDP single-controller SDN vs. Multi-controller SDN. ### Single-Controller UDP SDN vs. Multi Controller UDP SDN

In this section, we contrast a topology with a single SDN controller with one with multiple (in this example, three) SDN controllers. In this topology, there are 41 network devices total, including 30 computers, 8 OpenFlow switches, and 3 SDN controllers. In the single-controller topology, there are 39 network devices total, including 30 computers, 8 OpenFlow switches, and one SDN controller. We tested both networks for 180 s while setting the bandwidth to 1.05 Mbps and exclusively using UDP protocol packets. Figure 14 shows that both topologies--single-controller and multi-controller--show an average fluctuation of 0.01 Mbps, a very negligible fluctuation. As a result, we can conclude that both topologies perform exactly as they should. When compared to the single-controller test network, the multi-controller network performs somewhat better. It follows that a very big network will benefit from the multi-controller's superior performance. Figure 15 shows that there is little to no difference in the throughput of the two topologies, indicating that they are both transmitting data at nearly the same pace. This suggests that the two topologies behave at the same pace. Although when compared to the single-controller test network, the multi-controller network performs somewhat better. It follows that a very big network will benefit from the multi-controller's superior performance. It is evident from the aforementioned graph that the jitter for both topologies varies, but the average value of jitter for both topologies equals 0.02 Kbps for single-controller SDN and 0.0202 Kbps for multiple controller SDN, which is almost the same. The multi-controller routing information is added to the blockchain. As a result, we can state categorically that multi-controller network topology is superior to a single controller. However, the multi-controller performs better in terms of jitter fluctuation in the event of any breakdown. However, if a single controller quits functioning, the entire network fails. ## 5 Conclusions

This work presented a Lightweight Secure Framework that blends Software-Defined Networking with blockchain technology. The mininet network simulator is used to model the proposed SDN framework. The data transfer rate or network throughput, bandwidth variation, and jitter have all been used to assess the performance of single-controller-SDN and multi-controller-SDN networks.