View Full Version : IP routing from a host connected to CM to a host on internet

02-06-09, 10:55 AM
Hi folks,

I would like a clarification regarding how IP routing happens between
a host connected to a router which is in turn connected to the LAN i/f
of a cable modem, and a host which is on the other side of CMTS
(internet). I am confused because this is not a regular network of
routers with the CM coming inbetween the host and CMTS.

| | |
| CM |------------------| CMTS |--------
| | | |
------------- -----------------
| Etherent port
| R | ---------Host A

I wanted to trace an IP packet from Host A to Host B.
Where will the DHCP server for hosts connected to router R be located
and also will I be able to run a routing protocol like RIP amongst the
routers connected to various cable modems in the cable n/w. I guess
that since CMTS is at ISP, BGP would be used beyond from CMTS to

Really appreciate if someone could please explain this in detail.
I am having a lot of trouble understanding this.