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240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

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Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#61

Post by NavinF »

aidenn0 wrote: post #55
ijhuygft776 wrote: post #17

Earlier quoted context omitted.

> wifi has always been like that not for me

Nor for me; I have a 3000 square-foot house and run a single access point; I ran Ethernet to a very central place (we have a centrally located open stairwell between the two floors, which helps) and got a PoE WAP that covers essentially the whole house (if you hold your phone in the very corner of the corner rooms, you can get it to drop).

> if you hold your phone in the very corner of the corner rooms, you can get it to drop

See clearly we have very different standards. If you're seeing packet loss in the corner of the room, there will also be a fuckton of L2 retransmissions throughout the room. The latter will not be visible as ping loss%, but it has the same effect on p99 latency

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#62

Post by NavinF »

derefr wrote: post #58
NavinF wrote: post #12

Earlier quoted context omitted.

Jokes aside, I get a consistent 1600mbps over wifi 6E which is good enough for me. Of course you need an AP in every room to get consistent performance, but wifi has always been like that. And unless your applications use forward error correction wifi will always have latency spikes from L2 retransmission if there's even one wall between the AP and device

Consider: the faster the packets go, the faster the channel gets free to let other TDMA stations talk. A big office with a lot of computers still experiences QoS losses over 6E when someone starts watching a 4K video. Get those bursts of video-buffer-filling done faster, and other traffic will stay smooth.

Oh absolutely! That's the main reason why every room needs an AP. A 20mbps 4K video only uses up 1% of the air time for wifi 6E. Any more than that will noticably increase p99 latency. A device outside the room could easily use 10x as much airtime for the same bitrate.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#64

Post by aidenn0 »

NavinF wrote: post #61
aidenn0 wrote: post #55

Earlier quoted context omitted.

Nor for me; I have a 3000 square-foot house and run a single access point; I ran Ethernet to a very central place (we have a centrally located open stairwell between the two floors, which helps) and got a PoE WAP that covers essentially the whole house (if you hold your phone in the very corner of the corner rooms, you can get it to drop).

> if you hold your phone in the very corner of the corner rooms, you can get it to drop See clearly we have very different standards. If you're seeing packet loss in the corner of the room, there will also be a fuckton of L2 retransmissions throughout the room. The latter will not be visible as ping loss%, but it has the same effect on p99 latency

I guess I don't do things on my phone that are that latency sensitive. Web browsing used to be latency sensitive, but now the typical website does nothing for 250-750ms when I click on a link, and (seemingly randomly) takes multiple seconds about 5% of the time even if I'm connected via GigE, so any network latency is masked by that pretty well.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#65

Post by glitchc »

NavinF wrote: post #38
glitchc wrote: post #15

Earlier quoted context omitted.

An AP in every room, incorporated into the light fixture. Sounds like a business model just waiting for some funding.

Why incorporated into the light fixture? I paid ~$280 for each U6 Enterprise and that's the only thing that limits how many I have. I'm sure it's the same for anyone that cares about wifi performance. How much of a premium would you pay for better aesthetics?

You placed one in each room right? Each room has at least one light fixture. AP becomes invisible, saves space.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#66

Post by NavinF »

glitchc wrote: post #65
NavinF wrote: post #38

Earlier quoted context omitted.

Why incorporated into the light fixture? I paid ~$280 for each U6 Enterprise and that's the only thing that limits how many I have. I'm sure it's the same for anyone that cares about wifi performance. How much of a premium would you pay for better aesthetics?

You placed one in each room right? Each room has at least one light fixture. AP becomes invisible, saves space.

Space on the ceiling where I have essentially unlimited space?

I'm not saying there aren't advantages to this idea. Eg powering the APs with 120V from the light fixture would mean they can use fiber instead of PoE 2.5G ethernet. That would save me the cost of an extra switch and also reduce power consumption on both sides of the cable. But I'm sure a combined light+AP unit would be expensive enough to make that a moot point. If anything, I'd prefer to sacrifice even more aesthetics and use a bare PCB to save money if I could.

Re: 240-Gbit/s sub-THz wireless communications using ultra-low phase noise receiver

#67

Post by NavinF »

aidenn0 wrote: post #64
NavinF wrote: post #61

Earlier quoted context omitted.

> if you hold your phone in the very corner of the corner rooms, you can get it to drop See clearly we have very different standards. If you're seeing packet loss in the corner of the room, there will also be a fuckton of L2 retransmissions throughout the room. The latter will not be visible as ping loss%, but it has the same effect on p99 latency

I guess I don't do things on my phone that are that latency sensitive. Web browsing used to be latency sensitive, but now the typical website does nothing for 250-750ms when I click on a link, and (seemingly randomly) takes multiple seconds about 5% of the time even if I'm connected via GigE, so any network latency is masked by that pretty well.

Every website I use (besides reddit and wikia/Fandom) load almost instantly.

> typical website does nothing for 250-750ms

Two common causes:

- Your HTTP cache is slow because your workload size is larger than your SSD's SLC cache. Cheap 1TB SSDs only have 50GB SLC which gets nuked with every background software update, so buy a better one.

- your p99 DNS response time is slow. Recall that many websites require many DNS queries to randomly generated subdomains and the whole page is limited by the slowest response. Set prefetch=true in unbound and use multiple DNS servers in parallel with pihole/dnsmasq to eliminate that issue.

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