Welcome to our final module, Troubleshooting TCP and UDP‑related Issues.
If you've been an IT professional for more than 30 seconds,
then you already know you'll encounter issues. During this
module, we'll be discussing common and not‑so‑common
issues related to TCP and UDP.
But we'll also discuss how to resolve those issues.
The first issue we'll discuss is firewall issues in relation to TCP,
and this is probably one of the most common issues that you'll encounter.
The next issue we'll cover for TCP is destination NAT,
also known as DNAT. DNAT issues are most common when
serving a website to the internet.
The third and final TCP issue we'll work through is MTU
and MSS issues in relation to VPNs.
This issue is most common when working with ISPs that use long‑range wireless
infrastructure. During our troubleshooting of UDP, we'll first work through
the various issues that arise through the use of firewalls with UDP. Finally,
we'll end this module by working through issues associated with incorrectly configured UDP services.