Semi-complicated Home Network
 

I'm redoing my home network and running into some problems.
We have dsl and 5 static ip addresses.
What I would like to do is have 2 lans with routers and 3 others for various other things (i.e. we haven't decided yet).
I have the neccessary ip's, gateways, subnet mask, and dns servers.
I have hooked router1 and router2 (each with a different ip) up to the hub that hooks up to the modem.
Here is the problem, when I am trying to use both I have collision problems.
For testing, I've been having been running pings to my isp on a computer on each router. One will ping fine for 20 pings or so and then timeout for a while. The other router will behave in the opposite manner.

So to finish, any suggestions on how to clear up this mess to it runs correctly?


Really Crude drawing of the network:

while the routers have different IPs do they have different subnets?

setup your routers like cyn said.

Router 1: 192.168.1.0
Router 2: 192.168.2.0
Router 3: 192.168.3.0 and so on

If both routers are set to 192.168.1.0 then of course you're going to have collisions. Since you're being able to ping for a few seconds, thats the CSMA/CD protocol kicking in.

Carrier Sense Multiple Access/Collision Detect is the protocol for carrier transmission access in Ethernet networks. On Ethernet, any device can try to send a frame at any time. Each device senses whether the line is idle and therefore available to be used. If it is, the device begins to transmit its first frame. If another device has tried to send at the same time, a collision is said to occur and the frames are discarded. Each device then waits a random amount of time and retries until successful in getting its transmission sent.

CSMA/CD is specified in the IEEE 802.3 standard.

I understand CSMA/CD, well what it does if not how to explictly avoid it.

Anyway, my subnet masks are all set the same: 255.255.255.248.
If I understand where you're going, should the next 5 masks be:
1. 255.255.255.249 - 11111001
2. 255.255.255.250 - 11111010
3. 255.255.255.251 - 11111011
4. 255.255.255.252 - 11111100
5. 255.255.255.253 - 11111101
?

EDIT - Wait did I get that right?
I don't get how I'm supposed to set the subnet correctly.
Is it just a matter of changing the subnet mask as I said above?


Thanks for the help by the way.

I may be way off but.... I think your subnet masks should be 255.255.255.0 if you set up the routers like bendsley said, so each 192.168.XXX would be a seperate network.

Hmm, I personally think that if you have two LAN's, you need to connect them with a bridge.

It's the bridge's job to either a) ignore traffic that doesn't need to cross over or to b) route over traffic that does.

forget about subnet masks, for that address subnet, just make it 255.255.255.0. You're not going to fill up each subnet with that many computers to have the need to change subnets.

xxx.xxx.xxx.xxx or first octet. second octet.third octet.fourth octet

the third octet is your subnet.

the subnet and subnet mask are different.

Ok I understand that I was looking at the wrong thing.

But I still am not sure how I am supposed to set the subnet.
I am using a couple of Linksys routers( WTRG54 and BEFSR81).
I have the following things (using made up variables for my sake and readability):
IpAddresses: w.x.y.(z1|z2|z3|z4|z5)
IpNetmask: 255.255.255.248
Gateway: w.x.y.z0
2 DNS servers

Using one of the routers, shouldn't I just need 1 of the ip's, the mask, gateway, and the dns servers. I would set the local mask to 255.255.255.0 and the local ip for the router to whatever.

I guess I'm not sure where I'd actually use (or setup for that matter) the other subnets.

Sorry if I'm a little think on this. I've never set up more than a single router network.

What hardware is doing the DSL connection, and does it have routing capabilities as well, are you running NAT on the DSL device and are you intending the networks behind the Linksys devices to be DHCP assigned?

If you wanted to use 192.168.1.0/29 (255.255.255.248) as your subnet mask, then your networks would look like this (the subnet masks shouldn't change):

192.168.1.0
192.168.1.8
192.168.1.16
192.168.1.24
192.168.1.32

And it would only give you 6 hosts per network

By the way, what bendsley suggested is 192.168.1.0/24 (255.255.255.0).

Oops, I thought you wanted your internal subnet masks to be 255.255.255.248. I see now that that is the subnet mask of your external IP.
I think this is how you would likely setup the routers behind the hub -- which strikes me as an odd way to do things (I would probably put in a switch instead of a hub, or even a router but that setup is more complicated, and prone to configuration problems).

Network 1.2.3.0/29 (suppose this is the network assigned by your ISP)
Subnet mask (255.255.255.248, the /29 above)
Broadcast 1.2.3.7
External IPs: 1.2.3.1 - 1.2.3.5 (assuming you only have 5 of the possible 6)

Router 1:
external IP - 1.2.3.1 (suppose this is one of your external IPs)
subnet mask - 255.255.255.248
LAN Network - 192.168.1.0
LAN Broadcast - 192.168.1.255
LAN Subnet mask - 255.255.255.0
LAN IPs 192.168.1.1-192.168.1.254 (use as you wish or setup DHCP)


Router 2:
external IP - 1.2.3.2 (suppose this is one of your external IPs)
subnet mask - 255.255.255.248
LAN Network - 192.168.2.0
LAN Broadcast - 192.168.2.255
LAN Subnet mask - 255.255.255.0
LAN IPs 192.168.2.1-192.168.2.254

... Repeat procedure for routers 3-5

It's been a while since I did any networking so hopefully I haven't messed anything up. If anyone sees errors, please point them out.

Thanks
It turns out our line to the isp got hosed up some how recently. BEcause of this I wasn't able to correctly diagnos my problems.
I pretty much have it like you said now.

And for anyone who cares, the 6th ip in this case is the gateway (the modem/router).

Oh also I did switch the hub to a switch. I thought that the hub would function in more or less the same manner, but I guess not. I thought abotu a router instead, but don't have one available at the moment.


Thanks again for the help guys.