TamTam roundup.

[Carl-Daniel Hailfinger]

On 20.05.2007 08:20, John Watlington wrote:
> On May 20, 2007, at 2:01 AM, Hal Murray wrote:
> 
>> One obvious alternative for olpc is to have a magic DNS name that  
>> resolves to
>> the local NTP server.
> 
> Maigc DNS names at your service.  And since the DNS server used by a  
> laptop in a school setting will also be the closest mesh portal, the  
> NTP server can be the closest on the mesh.

Please don't reinvent the wheel. Yes, it's fun, but if you ever sat
in an internet cafe wondering why you get no connection, only to find
out later about the wonders of WPAD via DNS, the fun immediately stops.
If any magic name has to be used, try pool.ntp.org. Maybe not nice,
but better than a newly invented name.

There is a standard for time serving via DHCP.
Quoting from http://www.iana.org/assignments/bootp-dhcp-parameters
> DHCP Options are listed below:
>     4      Time Server              N    N/4 Timeserver addresses              [RFC2132] 
>    42      NTP Servers              N    NTP Server Addresses                  [RFC2132] 
>    100     PCode                    N    IEEE 1003.1 TZ String                 [RFC4833]
>    101     TCode                    N    Reference to the TZ Database          [RFC4833] 

http://tools.ietf.org/html/draft-ietf-ntp-ntpv4-proto-05 and
http://tools.ietf.org/html/rfc4330 have suggestions how to implement
NTPv4 and SNTPv4 server auto-discovery with tips for handling
networks with significant propagation delays.

Regards,
Carl-Daniel