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NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:12
Reviews:
·SONIC.NET
·Pacific Bell - SBC
reply to pcolasteve

Re: [Other] Configurable Modems (Cable / DSL)

said by pcolasteve:

I have two separate networks with two separate WAN IPs. In each network the modem, (DSL or Cable) is used as the csu/dsu giving access to the WAN. Attached to those are Cisco routers. The commercial, consumer grade modem will not communicate with the router allowing access to the WAN because the routing protocols are different. This is what I am talking about.

For cable, the signal rides on coax between the CMTS and the modem. Signaling is, I believe, based on DOCSIS standards. The modem bridges the coax (HFC) signaling and the Ethernet link. What is there to configure?

For DSL, the signal rides on a copper pair between the DSLAM and the modem. Signaling is based on ADSL, ADSL2+, VDSL, or VDSL2 standards. Most modems auto-detect the virtual circuit pair, and about the only user configuration deals with authentication; PPPoA, PPPoE, or none (DHCP).

With a pure modem, bridging is possible; but the damned RGs ISPs are issuing these days don't seem to bridge well, if at all. I have a Pace 4111N which fails to connect in bridge mode. The last pure DSL modem I found is no longer in production.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum