Re: [Ntp] Symmetric mode

Danny Mayer <mayer@pdmconsulting.net> Sat, 24 September 2022 22:08 UTC

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Date: Sat, 24 Sep 2022 18:08:20 -0400
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From: Danny Mayer <mayer@pdmconsulting.net>
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Subject: Re: [Ntp] Symmetric mode
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On 9/21/22 8:17 PM, Hal Murray wrote:
> mayer@pdmconsulting.net said:
>>> What's the difference between Symmetric and a pair of client/servers?
>> Symmetric peers keep track of each other while the server in  client/server
>> doesn't care, it's just responding to just another request.
> Right.  That's why I said "pair" of client/servers.
>
> We are discussing 2 systems.  What if each system is a client using the other
> system as a server?
>
>
> You have to edit both config files.
> It uses twice as many packets.

No, it doesn't. Run it and check the packet traffic. Yes each side sends 
a packet to the other the same as if both were referencing the other as 
servers

> It works with NTS.
NTS dropped it in the interested of getting NTS out.
>
> You don't have to worry about bad guys setting up symmetric connections.

We don't. I have no idea where this claim came from. A server that 
doesn't know the client sending a symmetric mode peer packet will not 
make it a peer and it will just act as responding to a client packet 
(with the asymmetric mode response).

Danny