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Internet and Data Circuit


Ours is a small retail company. The only cisco devices that are there are 2 877 ADSL's one for internet and the other is a 256K data circuit connected to our HO.

Issue: The data circuit is on a different IP range ( and the internet ( on other. I have already assigned 2 IP addresses to the user NICs.

At times the users with the multiple NICs lose their internet connectivity. What will be the optimum design for this network?

Thanks and regards


Re: Internet and Data Circuit


In the router do you have a default gateway point to the firewall interface?

A typical setup would be:-

1) Servers & PC's have a default gateway pointing to the router (Data Cxn HO)

2) The router (Data Cxn HO)has a default gateway pointing to the firewall (PIX FIREWALL)

3) The firewall (PIX FIREWALL) has a default pointing to the internet router KEMS.

4) The router (Data Cxn HO) has a static route for the data center IP subnet pointing to the router.

There should be no need fopr the user NIC's to have more than 1 IP address.



Re: Internet and Data Circuit

An optimum design would be to not have the users PC having two nics on two different networks.

(basically making the pc's do routing)

One optimum design would be to use a switch to plug both of the 877s into. You would have to change the IP Address of one of the 877s to the other 877s address range.

(this may involve getting your HO network admins to work with you on the routing)

ie: 877a 256k - ip; 877b internet - ip

Then setup the user pc's to have one NIC talk to the subnet. (you could then disable the 2nd nic in the pcs)

You would then need to make sure your 877s have the proper routing. Your user pc's could have a default gateway to; and 877a would have all required routes to HO and a default route to for access to the internet.

Another optimum design would have a router between the 877a and 877b. It would be configured with two ethernet interfaces, one to a switch that the 877a also plugs into and one to the 877b; this would allow the router to do the routing between the two IP subnets.

You would then disable one nic on the pc's and setup the other nic to talk to the router interface connected to their LAN.

Bottom line in your case is an optimum network would not use 2 NICs in the pc's to two separate networks.