portls

Portls, also known as port scanning or port probing, is a technique used in computer networking to discover which ports on a remote host are open and accepting connections. This process involves sending specially crafted packets to a range of potential port numbers on a target IP address and observing the responses. Different types of scans exist, each with varying levels of stealth and information gathering capabilities.

The most common types of port scans include TCP SYN scans, which are relatively fast and stealthy by not completing the full TCP handshake, and TCP connect scans, which establish a full connection and are therefore more easily logged by the target system. UDP scans are also employed to identify open UDP ports, though these are typically slower and less reliable due to the nature of the UDP protocol.

Port scanning is a fundamental tool for network administrators to assess the security posture of their systems by identifying potentially vulnerable services. However, it is also utilized by malicious actors to identify potential entry points for attacks. Unauthorized port scanning can be considered an intrusive activity, and many network security devices are configured to detect and block such attempts. Understanding port scanning is crucial for both network defense and ethical security assessments.