I have two cable modem, 30 computers. the cable modem provide dynamic
ip address. and 1 switch connect all 30 computers together. so, how
can I connect two modems with all 30 computers together. I need both
cable modem running and working. I try that with 1 router connect both
cable modem to router and another rj45 connect from switch to router,
but result is only 1 modem work for that router. both can't working at
the same time. if anyone has answer please response asap

Hi pckaiser-ga,

I’ve had a similar setup going at a LAN party recently with my
friends.  We had 16 computers and 3 cablemodems.  What we ended up
doing is having 3 ‘sharing’ computers, each with 2 nics (network
cards) and connecting them to 2 switches.

In your case, since you already have a router, you can save on having
to buy an extra nic for one of your sharing computers.  I’m assuming
you’re using Windows 98 or above (if not let me know).

Here’s the setup that will let you utilize both cablemodems.  First
divide your 30 computers into 2 groups.  How you divide the computers
is generally up to you but it’s best to separate the heavy bandwidth
users so that they’re on different Groups.  Group A will be using
cablemodem A and group B will be using cablemodem B.  Your ‘sharing’
computer for group A will have 2 nics in it.  If you’re using your
router, you don’t need a sharing computer for group B since your
router will be doing the sharing instead.  If you don’t want to use
your router, you’ll need another computer with 2 network cards in it.

Here’s how the connections will work:
Cablemodem A -> Group A sharing computer’s first nic
Group A sharing computer’s second nic -> Switch
Cablemodem B -> Router -> Switch
All other computers will connect directly to switch


For the Group A sharing computer, you will need to enable ICS
(Internet Connection Sharing).

On Win98, this is done through Control Panel, Internet Options,
Connections tab, Sharing button, and enable Internet Connection
Sharing and follow instructions on the wizard when it asks which
network card is connected to the cablemodem and which one is connected
to the switch.  Then open up Control Panel, Network, Properties for
TCP/IP of the network card connecting to switch, set the IP to
192.168.1.2 with subnet mask of 255.255.255.0.

With WinXP, it’s enabled through Control Panel, Network Connections. 
For the network adapter that’s connected to the cablemodem, right
click, Properties, Advanced, check first box under Internet Connection
Sharing.  OK all the way out.  Then right click on the network adapter
connecting to the switch, Properties, double click on TCP/IP, set the
IP to 192.168.1.2 with subnet mask of 255.255.255.0.

If you are not using a router, repeat the instructions above for Group
B’s sharing computer and use an IP of 192.168.1.1 for the network card
connecting to the switch.

If you are using a router such as Linksys, make sure it’s using a LAN
IP of 192.168.1.1 and a subnet mask of 255.255.255.0.  For routers
such as D-Link, the default LAN IP is 192.168.0.1 which you’ll have to
change to 192.168.1.1.  Microsoft’s router’s default is 192.168.2.1
which you’ll have to change to 192.168.1.1 as well.

Finally for every other computer on the network, you’ll need to go
into the properties of their network cards and set the gateway IP to
their Group’s corresponding sharing computer.  For example, a computer
from Group A will set its gateway IP to 192.168.1.2.  All Group B’s
computers will be set to 192.168.1.1.  This way, all computers will be
kind of load balancing between the two cablemodems.  You will also
need to give each computer a unique IP in the
192.168.1.3-192.168.1.254 range.  You may also need to set the DNS
servers on each computer as well to match the ones off the cablemodem.
 If you don’t know how to do this, let me know.

To set the gateway IP on Win98, open up Control Panel, Networks.
Properties for TCP/IP, Gateway tab, and add the corresponding IP
(192.168.1.1 or 192.168.1.2).

To set the gateway IP on WinXP, open up Control Panel, Network
Connections, right click on network adapter, Properties, double click
TCP/IP, set gateway to the corresponding IP (192.168.1.1 or
192.168.1.2).

This will let all your computers see each other in Network
Neighborhood (or My Network Places on WinXP) as well as access the
Internet.

The above setup, while similar, worked quite well at my LAN party and
everyone was generally happy with the speed compared to the last LAN
party we had where we only had one cablemodem.  Please let me know if
any of the above is unclear or if something doesn’t work.

Good luck,
mrbuzz-ga

To do this job correctly you need a second router.  You could use the
ICS, but a second router is cheap and a much better arrangement.  Have
the two routers on the same subnet (perhaps make the first one
192.168.1.1 and the second 192.168.1.2 -- whatever is compatible with
your current router setup).  You can use the DHCP server (automatic IP
assignment) in one of the routers & disable the other.  Both routers
plug into the existing hub or switch.

Now, just set half of the computers' default gateway addresses to
192.168.1.1, and the other half to 192.168.1.2.  That ought to do it.

I might be reading the answer wrong, but I don't see how, without some
sort of connection between the two groups, they would see each other
in network neighbourhood. YOu need some sort of gateway or bridge
between the two groups, which are actually 2 separate networks. What I
would do is this:

Have a router connected to each cable modem. each router is either
using an internal switch or is connected to the uplink port on a
separate switch. You're going to be connecting half of the computers
to one switch and half to the other switch. Setup one of the routers
to be 192.168.1.1 and the other to be 192.168.1.100, then set each
router to assign IPs only from the 99 IP addresses above it (2-99 and
101-200). Each PC will need to be configured to use one of the routers
for DHCP and gateway services, as well as all the other nice TCP stuff
like DNS.

Once you have 2 distinct networks working with internet access, and
every PC has a unique ip address that begins with 192.168.1. then it's
time to connect the 2 switches.

I'm not sure exactly the procedure, but I woud try:

1) A patch cable from one switch to the other
2) A cross over cable from one to the other.
3) A windows XP PC with 2 NICs, connected to each switch. In Netowrk
connections, click on one of the lan connections, right click on it,
and choose bridge this connection. When it asks you what to cridge it
to, choose the other lan connection.

Try it in that order, as the first two are simple. Basically, to test,
ping a PC on the other LAN from a PC on the first LAN. When they can
ping each other, there's a connection between your 2 LANs.

Hi, pckaiser-ga:

You don't mention what sort of router you have, but there are
commercial units which are designed for load balancing between two
cable modems.  While they are perhaps somewhat pricey for a LAN party,
for business use the cost seems small in comparison to the headaches
of maintaining distinctive configurations on subsets of machines.

Here's an advertisement for such a router, I'm sure there are
competing models:

http://www.broadbandbuyer.co.uk/shop/ShopDetail.asp?SupplierID=%25&CategoryID=2&Description=&Submit2=%3A%3A+GO+%3A%3A&offset=10&ProductID=156

regards,

:) 

there are couple ways to do this ..
first : buy a router that connects 2 or more cable modem  that does
load balancing ...(Best way)

second : use a computer to rout your cbale modem .. need 3
networkcards and Operating system than computer will become a router

third : you need two routers, divid the 30 computers into 2 group,
setup the router into 2 different IP(ex. 192.168.1.1 and 192.168.1.2),
set all the computer ip to static (ex. ip: 192.168.1.5  gatway :
192.168.1.1 or 192.168.1.2  DNS: need to match the router)