tcp/ip assumptions

[Thomas Tuttle]

I'm confused as to what you mean by a "relay" system.  If you mean it's
a router, then it should route the NTP packets fine.  If you mean it's
an HTTP proxy, then NTP simply doesn't work over an HTTP proxy.

I don't understand why you expect the XO to magically figure out how you
want your network to work.  NTP is routed over TCP/IP.  If you want it
to work, you have to provide TCP/IP routing to the server!  If you don't
want to, you can run an NTP server on your "relay" system.

There's nothing wrong with the XO making assumptions as to the external
services available, as the school servers will have NTP servers, and if
the laptop is on the mesh network, it will have access to the server.

If I've made an incorrect assumption here, or made a mistake, please let
me know.

Thanks,

Thomas Tuttle

On Mon, 28 Jan 2008 20:56:46 -0500, "Mikus Grinbergs" <mikus at bga.com>
said:
> I have a G1G1, which communicates via a local LAN to a "relay" 
> system, which communicates to the internet.  The server facilities 
> (*just* for the XO - not needed by the "regular" systems on my LAN) 
> I've now set up in the "relay" station are minimal (e.g., for DNS). 
>   The result is that many XO requests are not fulfilled by my 
> "relay" system (for instance, a separate dialog may be needed - 
> between the "relay" system and a *real* server out on the internet).
> 
> I was looking at a trace of the packets on my local LAN.  In the 
> case of DNS, the XO issues three "Type 28" requests (which my 
> minimal "relay" station does not support), before issuing a "Type 
> 01", to which it eventually does get an answer.  In the case of NTP, 
> the XO issues "scattershot" requests to all server addresses it was 
> able to extract [but receives no responses, because it tries to 
> contact them directly, rather than going through the 'proxy' 
> function in my "relay" system].
> 
> 
> My conclusion:  The tcp/ip function in the XO makes a number of 
> assumptions as to the type (and timeliness) of the external SERVICES 
> it expects to have been provided.  I would have been happier if I 
> had known about these beforehand, rather than having to discover 
> what does or does_not work in the environment I currently have. 
> [Might some setups in a target country be as minimal as mine?]
> 
> mikus
> 
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