Here's the scenario:
Small network home made of 3 PC's and 1 Linksys router for Internet access.
Linksys router IP: 192.168.1.1
PC1 IP address: 192.168.1.10 (mine)
PC2 IP address: 192.168.1.11 (my wife)
PC3 IP address: 192.168.1.150 (my kid)
I've assigned all 3 PC's with: Subnet mask = 255.255.255.128 / Gateway: 192.168.1.1
I've used subnet mask 255.255.255.128 in order to create 2 subnets. PC1 and PC2 are part of the 1st subnet (192.168.1.1-127) while PC3 is on the second subnet (192.168.1.128-255). I'm doing this so that I can somehow isolate a little bit more my son's pc from our 2 machines (I actually got that suggestion from another post in EE earlier this week). So by doing this, he cannot ping our computers from his. Makes me feel a "little" more secure - we are also running Symantec firewall on our PC's.
Now here's the part I don't understand: while PC3 (my kid) is not able to ping adresses 192.168.1.2 to 127 (works as expected), he IS ABLE to ping the router at 192.168.1.1 (not expected), and his Internet access works too. Shouldn't 192.168.1.1 not be reachable from his machine, like for adresses 2-127 ? Or is it because the Gateway IP address defined in his TCPIP properties takes precedence over the subnet mask ?
BTW, I'm quit happy that his Internet works in this scenario, but my understanding of this subnet configuration made me believe initially when I setup this up that he would not have access to the router / Internet.