Re: Question about DOCSIS DHCP vs ARP

[Jean-Francois Mezei <jfmezei_nanog () vaxination ca>]

On 13-01-11 19:59, Karl Brumund wrote:
> JF,
>
> Long ago been fixed. Look at Cisco CMTS config documentation, particularly cable-source-verify.

Many thanks. In particular, you need "cable-source-verify dhcp" to
prevent self assigned IPs that are unused by neighbours.

Is this something that is now basically a default for all cable
operators ? Or does this command add sufficient load to the CMTS that
some cable operators choose to not use it for performance purposes ?


What happens when a CMTS reboots and has an enpty database of DHCP
leases ? Does it then query the DHCP server for every IP/MAC it sees
that it doesn't yet know about ?