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Comment by tonyb | Hacker News Reader

This doesn't help you at all.

The provider is able to change the settings through two primary methods.

1. DOCSIS configuration file - this is the file your modem downloads when it comes online and includes settings like your speeds (Upstream/Downstream service flows) and it also includes the SNMP settings (used for #2).

2. SNMP - The MSO can also remotely monitor and change your modem via SNMP. There is a large number of DOCSIS MIBs that every cable modem must support in order to get certified and there are also vendor specific MIBs that a modems manufacture will add to support specific features of that modem.

Without SNMP it would be very difficult to maintain a cable network. Other types of access networks have similar features.

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Not sure I got that - why is cable different in this regard from DSL? I'm pretty sure there is such thing built into adsl/vdsl routers or modems, at least not in Germany.

DSL is provided over a POTS ("plain old telephone service") line. The demarc for POTS, at least in my neighborhood, is a grey box on the side of your house, well upstream of your DSL modem.

I don't know why exactly it worked out that way, but the telephone system is designed to deal with consumer electronics and the coax cable system is not.

It didn't used to be - until the federal government busted AT&T's monopoly, it was illegal to connect non-AT&T equipment to the AT&T network, at least electrically. This is why in old movies you see people dialing ISPs by hand with a phone and then setting the handset down on a cradle - the cradle was the modem, and it interfaced with the telephone network acoustically. The demarc (at least as we know it today) was presumably introduced after the government told AT&T they had to let people have their own networks, rather than considering everything up through the phones to be part of the telco network.

These are called VRADs http://en.wikipedia.org/wiki/VRAD.

The demarc for your DSL is the modem. If you provide your own modem you still are subject to AT&T's rules. You cannot legally connect to sensitive national infrastructure (like the phone network) without the provider being responsible for your access.

As far as connecting equipment, that significantly predates divestiture. Most people point to Carterfone as the salient decision that changed this: http://en.wikipedia.org/wiki/Carterfone

In reality, there was actually a prior decision which I can't seem to find right now where AT&T refused to allow people to put plastic privacy guards over the mouth piece on the grounds that it would damage the phone network. Ludicrous, but sensible from an economic standpoint.

EDIT: Found it, 1956 Hush-a-phone: http://en.wikipedia.org/wiki/Hush-A-Phone_v._United_States

In short, Telecom is complicated, the demarc is important and you don't own any part of the network from the modem on up.

Source: I am a telecom junkie and I work at 2600hz, the open source telecom company.

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