[time-nuts] Time security musing - attacking the clock itself

Edgardo Molina xe1xus at amsat.org
Tue Dec 4 01:56:14 UTC 2012

NTP is not secure in nature. MD5 key exchange between client and server is the only secure feature up to now, for the client to be sure that he/she is getting a correct time sync to the desired server. On the other side if the server does not receive a matching MD5 key, it will simply ignore the petition. Beside that, NTP is a connectionless UDP service, it is based in the open exchange of data, not establishing a session like other protocols that use TCP. This eases the transfer of information but makes it difficult to set controls to the process.

On the other hand PTP is evolving to be a future protocol for time transfer. Nowadays it is superior than NTP in the LAN environment. 


Edgardo Molina
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On Dec 3, 2012, at 7:36 PM, Chris Albertson <albertson.chris at gmail.com> wrote:

> On Mon, Dec 3, 2012 at 4:51 PM, Scott McGrath <scmcgrath at gmail.com> wrote:
>> We really need to think more about the secure distribution of time products
> Is NTP not secure.  I know it can be secured but I think in practice people
> disable passwords.
> -- 
> Chris Albertson
> Redondo Beach, California
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