I am currently learning about network engineering and was in the middle of monitoring my ARP cache when I realised I could ping my Windows 10 laptop (192.168.0.12) from my Windows 10 desktop (192.168.0.15) but not vice versa.

I read that this may have something to do with my firewall settings, so I took a look under the Inbound and Outbound Core Networking rules and found that on both machines I had the the same settings...

Inbound

Core Networking Diagnostics - ICMP Echo Request (ICMPv4-In): Private, Public, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv4-In): Domain, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv6-In): Private, Public, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv6-In): Domain, Enabled - no

Outbound

Core Networking Diagnostics - ICMP Echo Request (ICMPv4-Out): Private, Public, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv4-Out): Domain, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv6-Out): Private, Public, Enabled - no
Core Networking Diagnostics - ICMP Echo Request (ICMPv6-Out): Domain, Enabled - no

...so when I set the Inbound Public, Private IPv4 rule on the desktop to...

Core Networking Diagnostics - ICMP Echo Request (ICMPv4-In): Private, Public, Enabled - yes

...I was now able to ping both ways just fine.

I am just trying to understand why I was able to ping from laptop -> desktop with the default firewall settings, but in order to ping from desktop -> laptop I had to change them. Thanks for any insights into this