Many times I saw the phrase something 101, such as Microsoft Excel 101. What exactly does it mean?
meaning - What does "something 101" mean? - English Language & Usage ...
If I remove access-list 101 IN from my outside interface, then I can ping. If I put access-list 101 IN back on the outside interface, then I can't ping. Clearly I lack a fundamental understanding of what is happening when the router PINGs out. I want to block ping requests that originate outside my network.