https://www.protocolports.org/en/blog Latest from Blog en Fri, 12 Jun 2026 11:49:38 GMT https://www.protocolports.org/en/blog/common-ports-cheat-sheet https://www.protocolports.org/en/blog/common-ports-cheat-sheet A scannable reference of common TCP and UDP ports grouped by purpose — web, mail, file transfer, remote access, databases, and infrastructure. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT https://www.protocolports.org/en/blog/how-to-scan-ports-with-nmap https://www.protocolports.org/en/blog/how-to-scan-ports-with-nmap Learn how to scan TCP and UDP ports with Nmap: install, port selection, SYN vs connect scans, version detection, NSE scripts, and output formats. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT https://www.protocolports.org/en/blog/most-commonly-attacked-ports https://www.protocolports.org/en/blog/most-commonly-attacked-ports The internet-facing ports attackers hit first — RDP, SSH, SMB, databases — and the single most important hardening step for each. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT https://www.protocolports.org/en/blog/ports-to-block-on-firewall https://www.protocolports.org/en/blog/ports-to-block-on-firewall A practical guide to ports you should never expose to the internet — SMB, RDP, Telnet, databases and more — with the risk and a safer alternative for each. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT https://www.protocolports.org/en/blog/tcp-vs-udp https://www.protocolports.org/en/blog/tcp-vs-udp A clear comparison of TCP and UDP: handshakes, reliability, headers, real-world use cases, and why UDP fuels amplification DDoS attacks. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT https://www.protocolports.org/en/blog/well-known-registered-dynamic-ports https://www.protocolports.org/en/blog/well-known-registered-dynamic-ports Understand the IANA port ranges: well-known (0-1023), registered (1024-49151), and dynamic (49152-65535), plus how the 16-bit port space and ephemeral ports work. PortsDB Security Team Fri, 12 Jun 2026 00:00:00 GMT