Re: [Rpm] Almost had a dialog going with juniper...

[rjmcmahon <rjmcmahon@rjmcmahon.com>]

Here, look at this. Designed as a WiFi aggregation device.

https://www.arista.com/en/products/750-series

It supplies 60W PoE and claims support for 384 ports. Oh, the max 
distance per PoE AP is 100 meters.

That's insane as a power source and the 100M distance limit is not 
viable.

Our engineering needs to improve a lot.

Bob
> Cisco's first acquisition was Crescendo. They started with twisted
> pair and moved to Cat5. At the time, the claim was nobody would rewire
> corporate offices. But they did and those engineers always had an AC
> power plug nearby so they never really designed for power/bit over
> distance.
> 
> Broadcom purchased Epigram. They started with twisted pair and moved
> to wireless (CMOS radios.) The engineers found that people really
> don't want to be tethered to wall jacks. So they had to consider power
> at all aspects of design.
> 
> AP engineers have been a bit of a Frankenstein. They have power per AC
> wall jacks so the blast energy everywhere to sell sq ft. The
> enterprise AP guys do silly things like PoE.
> 
> Better is to add CMOS radios everywhere and decrease power,
> inter-connected by fiber which is the end game in waveguides. Even the
> data centers are now limited to 4-meter cables when using copper and
> the energy consumption is through the roof.
> 
> Bob
>> On Sun, Feb 19, 2023 at 3:37 PM rjmcmahon <rjmcmahon@rjmcmahon.com> 
>> wrote:
>>> 
>>> A bit off topic, but the AP/client power asymmetry is another design
>>> flaw similar to bloat.
>> 
>> It makes no sense to broadcast at a watt when the device is nearby. I
>> think this is a huge, and largely unexplored problem. We tried to
>> tackle it in the minstrel-blues project but didn't get far enough, and
>> the rate controllers became too proprietary to continue. Some details
>> here:
>> 
>> https://github.com/thuehn/Minstrel-Blues
>> 
>>> 
>>> Not sure why nobody is talking about that.
>> 
>> Understanding of the inverse square law is rare. The work we did at
>> google fiber, clearly showed the chromecast stick overdriving nearby
>> APs.
>> 
>> https://apenwarr.ca/diary/wifi-data-apenwarr-201602.pdf
>> 
>> 
>>> https://www.youtube.com/watch?v=Ey5jVUXSJn4
>> 
>> Haha.
>> 
>>> 
>>> Bob
>>> > Their post isn't really about bloat. It's about the discrepancy in i/o
>>> > bw of memory off-chip and on-chip.
>>> >
>>> > My opinion is that the off-chip memory or hybrid approach is a design
>>> > flaw for a serious router mfg. The flaw is thinking the links' rates
>>> > and the chip memory i/o rates aren't connected when obviously they
>>> > are. Just go fast as possible and let some other device buffer, e.g.
>>> > the end host or the server in the cloud.
>>> >
>>> > Bob
>>> >> https://blog.cerowrt.org/post/juniper/
>>> >>
>>> >> But they deleted the comment thread. It is interesting, I suppose, to
>>> >> see how they frame the buffering problems to themselves in their post:
>>> >> https://www.linkedin.com/pulse/sizing-router-buffers-small-new-big-sharada-yeluri/
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