[Leica] Epsom P800 Update

[Robert Baron]

Brian, I had been told that repeaters/extenders are not the way to go and
you have explained why very well.  Do you have an opinion on these new
'Mesh' routers?

--Bob

On Sun, Apr 22, 2018 at 4:42 PM, Brian Reid <reid at mejac.palo-alto.ca.us>
wrote:

> In a technologically perfect world, everything would be connected with
> wires. They are fast and reliable.
>
> WiFi is a convenient substitute for short wires, but it is not magic. If
> the WiFi sending and receiving unit have trouble talking to each other,
> they will slow down in the hopes of making it work.
>
> WiFi repeaters/extenders are a really bad idea. Here's why.
>
> Suppose you have devices A and B trying to talk to each other. A sends a
> message and B receives it. If, perchance, B is trying to send a message at
> the same time, then A's message does not get through and A has to try
> again. //??So does B, because its transmission was stepped on.
>
> If A and B are far apart and both of them are trying to send something, it
> can be a factor of 10 to 20 slower than it ought to be, because the
> airwaves are busy and unreliable and both ends are gyrating to find a time
> slot in which it is safe to send.
>
> Now add a single extender, M. A sends to M and M sends to B. The
> transmission pattern goes like this:
>
>     A sends to M
>     M sends to B
>
> this occupies exactly twice as much air time as A sending directly to B,
> so now a single transmission uses two slots instead of one. So if B is
> trying to send, there are two opportunities for interference, one with the
> A-M transmission and the other with the M-B transmission.
>
> When you print, the printer needs to respond that it has received that
> lump of data and is ready for the next one. So the conversation ought to go
> like this:
>
> A to B: here is some data
> B to A: thanK you. Send more.
> A to B: here is some data.
>
> If you have a repeater, the conversation goes like this:
>
> A to M: here is some data for B
> M to B: here is some data
> B to M: thank you. Send more.
> M to A: thank you. Send more
> A to M: here is some data
> M to B: here is some data
>
> If there is another computer in the mix, that is neither A nor B, then it
> is also trying to find a time slot that is not being used. The use of a
> repeater doubles the number of time slots needed for a conversation.
>
> I run wires as close as I can get them to where the computers and printers
> are, and then I use WiFi for the final connection.
>
> Also, all WiFi is not created equal. If you have a WiFi router that is
> older than 3 years you should drive a heavy truck over it. Unless you are
> an expert you should use WiFi routers that employ the 802.11ac protocol.
> That's "ac", not"ad" or "af" or "n" or anything else. "ac". Don't buy
> "802.11ac Wave2"; it is not ready for general use.
>
>
>
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