5.2.2. Computation Overhead

Figure 5 shows service processing time of key procedures in PoENF consensus given different platform benchmarks. As verifying a tx or vote only involves O(1) computation complexity, the service processing time is almost stable (about 2 ms for tx verification and 50 ms for vote verification) on all benchmarks. Compared to tx verification, which simply checks the validity of a tx then buffers it into system memory, vote verification involves more computation on resolving forks and database operations to store valid votes. Thus, vote verification incurs more latency than tx verification does. As the most computing intensive stages, both block mining and verifying rely on procedures in PoENF consensus algorithm with the computation complexity of <sup>O</sup>(*K*2*d*). Therefore, the computation cost on all devices dramatically increases as *K* is scaled up. Given different computation capacity of benchmarks, RPi-4 needs 2.5× processing time than Desktop does.

**Figure 5.** Computation overhead for stages of running PoENF consensus on host. Comparative evaluations on platform benchmark.
