Communicating Class A and Class C Networks
 

Hi there,
Can anybody explains, how Class A and Class C networks interconnected? I'm stuck with that since I try to connect 'em using linux ip aliasing method. Is it posiible?

I'm on Slack9 and I hope there's some suggestions regarding that.

I wanna make this happen in my network:

[1][the internet]
|
|
|
[2][a web-caching server]
192.168.0.1:4480
|
|
[100mbps Switch]
| | |
| | |----[3][the Slackware router+iptables with 1 NIC and two IP alias]
| | 192.168.0.103 [eth0]
| | 192.168.1.1 [eth0:0]
| |
| |-------[4][Win98 clients from room1]
| 192.168.0.xxx
|
|-----------[5][Win98 clients from room2]
192.168.1.xxx

My question, how could I make the these subnets communicate each other?
My priority is to make all traffic from [5] should go through [3] before it goes to [2].
Is this going to happen or "just forget about it?"

You need to set proper gateway for [5].

But the configuration you have described is very strange for me (apart from the poor drawing :) because:
1. usually router is the computer which is placed between "world" and LAN
2. router should have 2 NICs not connected to the same switch (or hub) - on the other case the firewall won't be able to play correctly
3. the cashing servers are usually inside LAN so they don't connect to the internet directly (but via router)
4. why the cashing server has not an public IP (or it has got but not shown?)

Is this means that the web-caching server should be connected to the router? The router acts as a gateway to the outside world.
I'm using IP aliasing for that to create some sort of two NICs. Is it possible or IP aliasing is just for anything else? I'm misinterpreted the term IP aliasing maybe... :)
The web-caching server is not having any public domain since it is used to speed up LAN internet access purposes only. It is not proxying apache to the outside world.

1. suggested topology is:
This way you can really separate internal LAN from the world (assuming correct firewall)

2. IP aliasing is nothing as far as security. Although 192.168.x.x are theoretically "non-routable" there is a lot of attacks with the packet which are crafted with source and/or destination IP addresses from this range.

4. So your drawing is incorrect - the line from internet goes to the web-caching server and next (another line) goes from server to the switch. To get such topology you need 2 NICs (like above)
BTW: public IP <> public domain

I have the exact (or so) architecture and it's working well.
The only difference is that I have a box acting as a router in the middle of all box. This "router" does NAT to internet AND external connection, so both subnet can talk.

Just do some search 'bout NAT, it's a great thing.

Sorry, but above sentences are contradictory.

LOL sorry my second sentences is bad. I meant that instead of having a switch thhe this switch connected to a linux router, I ONLY have a linux router ( a cool P120 with 4 networks card in it ). 2 of these network card are connected directly to computers, 1 of these is connected to an hub and the last to internet.
So :
INTERNET
|
|
|-------(Alone Computer) 192.168.0.2
(ROUTER)
|-------(Alone Computer) 192.168.0.3
|
|
|
(SWITCH)-------- 192.168.1.2
|------------ 192.168.1.3
|------------ 192.168.1.4

Is it clear now? ;)

geez. how many machines in each subnet are we talking about here? 200? 250?

3 in one, 2 in another I think :)

Sorry but I still don't understand.
As I wrote - typical router has 2 NIC so it is 2-port device.
How many ports the router has? Is it a multiport device?