Re: Reverse DNS RFCs and Recommendations

[Sander Steffann <sander () steffann nl>]

Hi,

Op 2 nov. 2013, om 12:16 heeft Masataka Ohta <mohta () necom830 hpcl titech ac jp> het volgende geschreven:

> Mark Andrews wrote:
>
> > A cable modem both accepts DHCP packets (for management of the
> > modem) and passes DHCP packets through to the customer device.
>
> Even if the CPE does so, which means there is no NAT, the key
> to update rDNS must, naturally, be contained only in DHCP reply
> to the CPE.

You are misunderstanding the technology. Many cable operators offer a cable modem in bridged mode so that the customer 
can attach his own home-router behind it. Sending keys over a medium shared between multiple customers is not safe.

Cheers,
Sander