Nscan
Nscan is a fast network scanner optimized for Internet-wide scanning. Nscan uses Raw sockets to send TCP SYN probes and has its own tiny TCP/IP stack. Nscan helps to extend our scan by chaining the IP and port found to another script where they might check for vulnerabilities, exploit targets, proxies or VPNs, and more. Nscan is a port scanner in itself, which use Connect()
method to find a list of host open ports.
Nscan is different from other port scanners due to its flexibility and speed. The maximum speed of previous versions was around 500 ports per second. But the maximum speed of port scanning mainly depends upon the bandwidth of the network and the processing speed of the system.
Tip
Read more on Nscan at, https://github.com/OffensivePython/Nscan.