Subject: [ntpwg] SNTP and NTP servers

From: Danny Mayer <[email-masked]>
Date: Mon, 03 Dec 2007 22:45:44 -0500

Just to clarify, SNTP clients can use both NTP Servers and SNTP Servers
while SNTP servers cannot be used for NTP clients unless the have a
refclock attached. Yes this a bit confusing but it is described in the
current NTPv4 draft. See Section 14 of the draft. The SNTP packets are
the same as the NTP packets.

Danny
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From: "David L. Mills" <[email-masked]>
Date: Tue, 04 Dec 2007 05:53:03 +0000

Danny,

The NTP specification defines primary servers, secondary servers and 
clients. Primary servers are synchronized to reference clocks and 
conform to the SNTP or NTP specification, which is the same. SNTP 
clients can synchronize to primary or secondary servers, but cannot 
offer synchronization to clients of their own. Secondary servers can 
import time from primary or secondary servers and provide time to 
dependent clients. Only they must provide the mitigation and discipline 
algorithms. This is to avoid possible whiplash or other suboptimal 
behavior. If you have alternate discriptions or verbage about the 
specification prose, I would be happy to hear it.

Dave

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From: "TS Glassey" <[email-masked]>
Date: Tue, 4 Dec 2007 06:01:03 -0800

Dave - I want to change the license for NTP so that people are not allowed
to use it for actions like what DLink did to various people on this list who
are still fielding its 'sales support' overhead.

It is exactly the NTP License that has caused all of the 'Bad 
Implementation' issues IMO. No one should be allowed a license to implement 
a 'portion' of the NTP service because it prevents the rest of us from being 
safe around it.

----- Original Message ----- 
From: "David L. Mills" <[email-masked]>
Cc: "NTP Working Group" <[email-masked]>; <[email-masked]>
Sent: Monday, December 03, 2007 9:53 PM
Subject: Re: [ntpwg] SNTP and NTP servers

> conform to the SNTP or NTP specification, which is the same.

IMHO - this is a problem not a solution. The SNTP handshaking/protocol
should be constrainable so that NTP Servers can refuse service to SNTP
Client's... The reason that Wisconsin happened is that a Commercial Entitiy
violated the generally accepted rules. The point is that the reason that was
possible is that the original license allowed them to. If the license had
been properly written, then anyone would have 'recourse' and what folks like
DLink did to Poul-Henning and myself would have been avoidable.

> SNTP
> offer synchronization to clients of their own.

I.e They can recieve synchronizations from NTP Servers,  but cannot in turn
offer that service to other client's. I.e. SNTP is limited to be used as a
receptor of time data and not a transmitter of it.

> Secondary servers can
> algorithms.

OK. My only pushback here is that there is NO mandatory implementation model
based on the "License" here - so we cannot control what is implemented and
what is not.

> This is to avoid possible whiplash or other suboptimal

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From: "David L. Mills" <[email-masked]>
Date: Tue, 04 Dec 2007 17:02:42 +0000

Todd,

I am not prepared to craft, delegate or defend any license except what 
is in the copyright statement. I've said this many times before, even on 
occasion throwing a lawyer wanting special dispensation out of my 
office. Please do not raise this issue with me again.

Dave

TS Glassey wrote:

> Implementation' issues IMO. No one should be allowed a license to 
> implement a 'portion' of the NTP service because it prevents the rest 
> of us from being safe around it.
>
> ----- Original Message ----- From: "David L. Mills" <[email-masked]>