Why does my android device does not respond to ping?

I connected an Android device and a Linux system on the same WiFi network. On pinging the android device from my Computer, the mobile does not respond to ping.

Is this a security feature (firewall) that prevents the response ?

I just tried it on my home network.

A samsung S5 = responded to pings.
A LG G3 = responded to pings.
A generic ZTE = responded to pings.

All running different versions of android.

If you have av/firewall apps running on the phone this is most likely the culprit.(mcafee/norton etc) Although the suggestions for the wireless access point configuration are equally valid.

Look for "isolation" settings within the routers internal configuration. To find the routers ip number use ifconfig from the terminal, it will be labeled "gateway".