Internet Access Router: Configuration Steps

Configuring an Internet access router involves several steps that include setting up the physical connections, configuring the interfaces, and configuring the routing protocols. Here are the configuration steps for an Internet access router:

Configure the hostname and enable secret password:

Router> enable

Router# configure terminal

Router(config)# hostname [hostname]

Router(config)# enable secret [password]

Configure interfaces with IP addresses:

Router(config)# interface [interface type and number]

Router(config-if)# ip address [ip address] [subnet mask]

Router(config-if)# no shutdown

Configure the default gateway:

Router(config)# ip route 0.0.0.0 0.0.0.0 [next-hop IP address]

Configure NAT or PAT:

Router(config)# ip nat inside source static [local IP address] [global IP address]

Router(config)# interface [interface type and number]

Router(config-if)# ip nat outside

Router(config)# interface [interface type and number]

Router(config-if)# ip nat inside

Configure dynamic routing protocols like OSPF or EIGRP:

Router(config)# router ospf [process ID]

Router(config-router)# network [network address] [wildcard mask] area [area ID]

Save the configuration changes:

Router# copy running-config startup-config

These are the basic steps for configuring an Internet access router. However, the specific configurations may vary depending on the network requirements and the type of router being used. It is important to carefully plan and test the configurations before deploying them in a production environment.

Routers sometimes have DHCP enabled on the Internet facing interface. DHCP server functions are enabled on the local interface with PAT functions enabled. Cisco supports an alternative configuration tool called the Cisco Router and Security Device Manager (SDM). To provide support for the SDM, the router must be configured with at least one IP address, typically on the local LAN. Cisco switches also allow web access for configuration, using a tool called Cisco Device Manager (CDM).

The SDM configuration wizard considers any interface that already have IP addresses configured as candidates to become inside interfaces for PAT. SDM uses a web browser on a PC and a web server function on the router, requiring the user to connect through an IP network rather than from the console. SDM does not use SSH. SDM loads the configuration into the router only after the user clicks the finish button on any of the configuration wizards, but the configuration is added only to the running config file.

Configuration Steps involves