[ntpwg] [dhcwg] NTP option: IP address and/or FQDN

[Richard Gayraud (rgayraud)]

Hello Alain,

This is not really different, but the impact of it will be less
important:

  - If an hardcoded NTP IP address is shipped within a SOHO thing,
    (as it happened in the past), then this IP address is dead, 
    for good. Not usable anymore. Also, I suspect routers on the
    path to this subnet are impacted, unless global internet
    routing tables are updated to drop this traffic upstream.

  - on the other side. If a DNS name is hard-coded, this IP 
    address and subnet issue can be avoided by removing the
    name from the DNS database. 

      . Clients are not supposed to re-query the DNS server
        every 2 seconds after the server replies the name is
        not resolvable.

      . even if they do, the load will be distributed over
        multiple local DNS servers (instead of having a
        single victim IP address).

      . we hope that a poorly coded SOHO equipment will use a 
        pool FQDN rather than a single NTP server name.

I think other people gave other good reasons to use FQDN, but
I do not remember all of them.

Does this help ?

Thanks,

Richard.

> -----Original Message-----
> From: Alain Durand [mailto:alain_durand at cable.comcast.com] 
> Sent: dimanche 9 décembre 2007 19:55
> To: Richard Gayraud (rgayraud); Danny Mayer; MORAND Lionel RD-CORE-ISS
> Cc: DHC WG; Ralph Droms (rdroms); NTP Working Group
> Subject: Re: [dhcwg] NTP option: IP address and/or FQDN
> 
> 
> 
> 
> On 12/9/07 10:16 AM, "Richard Gayraud (rgayraud)" <rgayraud at cisco.com>
> wrote:
> 
> >   => But more importantly, this does not give any guaranty 
> that a vendor
> >      will not ship a small home router with a DHCP server 
> inside, with an
> >      embeded NTP server address => worst case.
> 
> Excuse me if I'm just adding fuel to the fire, but I still 
> fail to see the
> difference between a vendor shipping a home router with a 
> DHCP server that
> has an NTP option embedding a hard-coded IP address and the 
> same vendor
> shipping a similar product with a hard-coded FQDN...
> 
>    - Alain.
>