I have a Cisco 2620xm router that I have ran into trouble getting it to connect to a comcast modem/gateway for internet service. The router and modem used by Comcast is a DPC3... The interfaces on the Cisco router are Aux, Console, Fast Ethernet 0/0, Ethernet 0 (Which shows in the terminal as Ethernet 1/0 and has a Serial )/0 port right next to it, looks group with it on the router), and at T1 WIC (CSU/DSU).
Does this require me to have another additional WIC card? Or can I use the Ethernet 1/0 port to connect the Comcast modem into? If I can't use either of the Ethernet ports to connect to a modem, would the T1 card be fine to use for regular Comcast high speed internet?
What I am trying to achieve here is a Cisco 2600xm router that will get its internet from a Comcast modem/router, then there will be a switch that will connect to the Cisco router to service other computers/servers in the network.
I would prefer for the Cisco 2620xm to grab its information/IP address using DHCP from the Comcast modem/router. I think I may need to upgrade the IOS on the router, but not sure how to get the upgrade onto the router.