connect 192.168.100.xxx with a 192.168.1.xxx network

[knot192]

Dear forum members

I am trying to connect a
Netgear RP614v4
my LAN with
the LAN (WAN) of our housing estate.
The router of the housing estate 192.168.1.1/255.255.0.0
connects then to the internet.

LAN LAN housing estate (WAN)
192.168.100.xxx/255.255.255.0 <> 192.168.1.xxx/255.255.0.0 <> Internet

----------
Netgear RP614v4 configuration
LAN:
DHCP Server: 192.168.100.1/255.255.255.0
DHCP Clients: 192.168.100.2 - 192.168.100.200 /255.255.255.0

WAN:
192.168.1.44/255.255.0.0
DNS: 192.168.1.1
----------
When I click 'update' and after the update process
this message pops up
--------------------------------------------------------------------------------
Important Update

To avoid a conflict with your Internet Service Provider, your router's IP
address has been updated to 10.0.0.1.

You must now update the IP addresses in your router's configuration
settings for each relevant service, such as port forwarding and
IP address reservation.
--------------------------------------------------------------------------------

Is there a solution to connect these two networks
with the specification nobody from
our LAN housing estate (WAN) 192.168.1.xxx can access 192.168.100.xxx (my private network)?
I don't wont to use a 10.0.0.0 or a 172.16.0.0 net
because I use the 192.168.100.xxx at many other locations.


Thank you for your help

Knot

[Walter1902]

Hallo Knot,

are you sure, that the subnet mask of your housing estate is 255.255.0.0.
That would imply that the sub-network address space is 192.168.0.0/16 and that all clients with IP addresses like 192.168.x.x will reside in this sub-network.
Typically the (standardised) subnet mask of C class networks is 255.255.255.0.

The problem in combination with your private network 192.168.100.0/24 is, that all clients with addresses like 192.168.100.* belong to both sub-networks, 192.168.x.x and 192.168.100.x. E.g. their membership to a sub-network is not clear and e.g. the router is not able to handle this ambiguity.

I suppose, that the correct sub-network address of your housing estate will be 192.168.1.0/24 (e.g. subnet 255.255.255.0). It seems as if the listed addresses and the title of your posting also show in this direction.

Kind regards from Germany, Walter

[jmizoguchi]

if both network was on class c subnet 255.255.255.0 then you could use double nat and WAN is 192.168.1.x and your RP's LAN can be 192.168.100.x

but because WAN uses class b 255.255.0.0, it will include the 192.168.100.x so you will need to use other than 192.168.x.x/25.255.255.0

use 10.x.x instead or IP of you choice other 192.168.x.x

netgear will change to 10.0.0.0 to avoid conflict and based on WAN with Class B, it will try to avoid. this is normal and nothing you can do.