Assigning subnetted IP address

[Siddharth Varma]

My ISP has given me the IP address of 192.168.22.7 with
Subnet Mask of 255.255.255.252 & Default Gateway of
192.168.22.1
The Default Gateway is a Linux Server & the IP is
subnetted so that one user cannot see or browse other
user's PC.
The first thing is ip address cannot be in 252 subnet as
it is a broadcast IP.
When I checked up with the ISP he said that the subnet
mask is 240 instead of 252
Every thing works fine when configured with 252 subnet &
also with 240 Subnet.
My query is how does connectivity establish if the PC is
in a different subnet & how can it ping the default
gateway. If I am not clear with the description kindly get
back.

 

[SteveC]

My ISP has given me the IP address of 192.168.22.7 with
Subnet Mask of 255.255.255.252 & Default Gateway of
192.168.22.1
The Default Gateway is a Linux Server & the IP is
subnetted so that one user cannot see or browse other
user's PC.
The first thing is ip address cannot be in 252 subnet as
it is a broadcast IP.
When I checked up with the ISP he said that the subnet
mask is 240 instead of 252
Every thing works fine when configured with 252 subnet &
also with 240 Subnet.
My query is how does connectivity establish if the PC is
in a different subnet & how can it ping the default
gateway. If I am not clear with the description kindly get
back.

Hello,

with the following IP scheme:
192.168.22.7 with mask 255.255.255.252:
192.168.22.5 to .6 are valid ip addresses.
192.168.22.7 is the broadcast address for your subnet.
192.168.22.4 is your network address

with the following ip scheme:
192.168.22.7 with subnet mask 255.255.255.240:
192.168.22.1 to .14 are valid ip addresses.
192.168.22.15 is the broadcast address for your subnet.
192.168.22.0 is the network address.

Your default gateway was properly configured so it knew how to find
the 192.168.22.0 / 255.255.255.240 network, even with the
misconfigured setting of 192.168.22.7 / 255.255.255.252.

Your computer is able to locate the default gateway using an ARP
broadcast because the two devices share the same media.
Computers talk to each other using MAC addresses. They use the
destination IP address to help find the destination MAC address.

Connectivity between two devices on different networks or subnets
depends greatly on the proper configuration of the router that serves
as the default gateway.

This is a simple summary of the process. I hope it made things
clearer. Let me know if you have any more questions.

regards,

SteveC
======
If at first you don't succeed, forget skydiving

 

[Reni Ninan]

Assuming that the router (Linux server) was properly configured with the
correct values, 192.168.22.7 would appear as a valid network to the router.

 

[Reni Ninan]

I saw that SteveC had already provided a more detailed response - sorry for
the duplication.