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Basic Router Setup

Thank you for your Question.  So a basic setup to get you going and to get all 5 of your computers online you will need a DHCP and NAT. The nice thing is you will only need to configure the Router. I have created from your email what I think is the network you currently have.

So to configure the router we have to do a couple of things.

1. Setup Port on Router for DHCP from Modem
2. Setup DHCP Server on Router
3. Setup Nat

To get started console in to the Router, and get in to Config mode.

Router> en

Router# Conf T

Router(config)#

Then let’s run some commands.

Hostname YourNameHere

Ip dhcp pool Pool1

Network 192.168.100.0 255.255.255.0

Default-router 192.168.100.1

Dns-server 4.2.2.1 4.2.2.2

You now have a DHCP Server running on your router. Time to configure the ports.

interface fa0/0

 description External connection to Modem

 ip address DHCP

 ip nat outside

 ip nat enable

ip virtual-reassembly

duplex auto

 speed auto

interface fa0/1

 description internal

 ip address 192.168.100.1 255.255.255.0

 ip nat inside

 ip nat enable

ip virtual-reassembly

duplex auto

 speed auto

So your ports are now configured.  As long as your Modem is providing a DHCP address to the router you should be good to go.  There are still a few more things we will have to do to get this up and running.

ip default-gateway fa0/0

ip classless

ip route 0.0.0.0 0.0.0.0 fa0/0

ip nat inside source list 7 interface fa0/0 overload

 That’s it. You should be good to go.