> For the complete documentation index, see [llms.txt](https://cybersecurity-cloud-and-it-notes.gitbook.io/kyles-cybersecurity-cloud-and-it-gitbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cybersecurity-cloud-and-it-notes.gitbook.io/kyles-cybersecurity-cloud-and-it-gitbook/testout-ccna-training/lessons/section-2.1-tcp-ip-networking-model/2.1.9-tcp-and-udp-port-numbers.md).

# 2.1.9 TCP and UDP Port Numbers