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Comment by rsynnott | Hacker News Reader

5G is (at least on paper) _very_ low latency; couple of ms.

It is not on paper. Couple of ms ( 4ms ) is real, except it is not normal 5G but specific superset / version of 5G.

Your network needs to be End to End running on 5G-A ( 3GPP Rel 18 ) with full SA ( Stand Alone ) using NR ( New Radio ) only. Right now AFAIK only Mobile networks in China has managed to run that. ( Along with turning on VoNR ) Most other network are still behind in deployment and switching.

Although the deployments are very limited, wouldn't the 5G mmWave coverage, in NFL stadiums for example, need to have both New Radio (NR) and Stand Alone (SA)? Or is there some bodge for down-rating your mmWave experience to a non-Stand Alone network? I understand you won't get SA end-to-end calling an endpoint on an LTE network, but, with 5G FWA also needing SA to achieve full performance, SA should be pretty widespread in the US, or is it?

US Stadium mmW deployments and showcases at marquee sporting events happened well before SA was ever out of the labs.

On that note, the BBC deployed a temporary 5G SA non-public-network to broadcast King Charles' Coronation, giving over 1Gbps uplink over 1km of the procession route. More details are in the award-winning white paper linked from this[0] blog post.

[0]: https://www.bbc.co.uk/rd/blog/2023-05-5g-non-public-network-...

I could not imagine any private news-gathering organization to set up a temporary cell network for coverage.

Eh, I wouldn't be that surprised if it happens from time to time for big events. You'd be talking the very big sophisticated ones, but it is possible to get temporary licenses, and the equipment isn't _catastrophically_ expensive, particularly if you're just renting it.

This: https://en.wikipedia.org/wiki/Chaos_Communication_Congress usually has a temporary cell network (I think up to LTE last year) set up for the duration of the event, on a temporary license. And that's basically just done for fun.

I know a few companies that have managed to get the license to do it.

F1 TV also gets radio spectrum which they use for something like 4G for their wireless cameras.

It is until you congest it. Then, like all other network technologies, performance collapses. You can still force traffic through with EDC, buffering, and re-tries, but at massive cost to overall network performance.

Cellular technologies can be configured to degrade differently to WiFi. The device gets fewer assigned slices, so the bandwidth reduces, but latency should remain static.

How does voice call quality degrade? Does it switch to a tinny bit rate?

On 4G or 5G, if voice quality is degrading it's either being switched to a lower quality codec, or it's an upstream issue.

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