This chapter presents some interesting Python recipes for network security monitoring and vulnerability scanning. We begin by sniffing packets on a network using the pcap library. Then, we start using Scapy, which is a Swiss knife type of library that can do many similar tasks. Some common tasks in packet analysis are presented using Scapy, such as saving a packet in the pcap format, adding an extra header, and modifying the IP address of a packet.

Some other advanced tasks on network intrusion detection are also included in this chapter, for example, replaying traffic from a saved pcap file and broadcast scanning.