Reverse DNS RFCs and Recommendations

Mark Andrews marka at
Sat Nov 2 11:38:12 UTC 2013

In message <5274DEF9.3040405 at>, Masataka Ohta writes:
> Mark Andrews wrote:
> >> Over the cable modem?
> > 
> > Yes.
> OK.
> >> The cable modem is the CPE, which accept the DHCP packet to it.
> > 
> > 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.

A cable modem is a media converter.  That can be managed and that
management interface also uses DHCP is irrelevent.

> And, I'm afraid your draft assumes that the CPE behaves as a
> DHCP server for local hosts, which means the CPE is responsible
> for rDNS registration.

My draft assumes the CPE device is a PD client.  It may or may not
be a DHCP server for the internal network.  Again that is irrelevent.

> 						Masataka Ohta
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

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