The mystery of very slow 2degrees data speeds in some parts of New Zealand has been solved by the telco finally admitting that it has introduced a restriction in some areas.
Long story short: 2degrees still uses parts of Vodafone's national network in areas where it doesn't have coverage; and, 2degrees customers who roam onto Vodafone's network get really slow performance despite being promised 3G speeds.
Why it was necessary to do that 2degrees would not say however.
2degrees appear to have done this on the quiet. National roaming onto Vodafone's network was mostly OK for 2degrees customers until some point in time when the telco put the brakes on, and a long thread on tech forum Geekzone kicked off in June last year.
The 2degrees coverage map says Great Barrier Island where a Geekzoner first noticed the "insanely slow speeds" of around 300 kilobit/s downloads and 800 kbps uploads has "3G Boosted" service.
This is defined by 2degrees as "voice, text & fast internet services with wider coverage for those with 3G 900MHz capable devices."
Anyone reading that would reasonably expect decent wireless broadband speeds because, well, it says that.
Apparently the speed restriction only applies to less than one per cent of 2degrees coverage, where they pay for access from Vodafone but it would be helpful to know where that is.
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It is disappointing that 2degrees social media people jumped in on Twitter to deny that there's a restriction without checking first.
2degrees now promises to spend more money to expand the coverage. Until that work is done, the telco should at least warn customers which areas have restricted performance and not tell customers they can expect "3G Boosted" in them.
Mobile telecommunications terminology is loaded with confusing acronyms and to the surprise of nobody, 5G really ladles it on.
My apologies, but here's what Vodafone will boot up in December: 5G NR NSA n78 3GPP R15 TDD.
Being perhaps a bit special, I know what the abbreviations refer to but there were still a few unclear areas that Nokia's Customer Team Head Vodafone and Pacific Rob Spray helped clarify.
First, Vodafone's 5G New Radio Non-Standalone (NR NSA) service runs in the 3.5 GHz band which is what n78 denotes.
There's no millimetre wave carrier yet, 28 GHz or otherwise, for super-fast wireless broadband.
That's for later with more money to be spent as it involves adding even more base stations close to each other as high frequencies have short reach, don't go through objects and reflect off them instead. Millimetre wave 5G will be in cities only for that reason.
Following the current release 15 of the 5G standards that telcos and equipment vendors have agreed to at the 3GPP industry forum, Vodafone's next-gen service uses the existing 4G or Long Term Evolution (LTE) tech which might surprise some.
LTE is the control plane for setting up and managing voice, text and data connections. In other words, 5G won't work without 4G and devices need to support both technologies.
It was suggested to me that data uploads would go over LTE. You can do that with 5G, but that is not how Vodafone NZ will do it Spray said.
Spray explained that once the 5G connection is up, all traffic will go over that interface.
Using 4G like this is a compromise to get 5G out of the door faster for telcos. Vodafone's a bit touchy about this, with a spokesperson telling me "this is genuine 5G" rather than 4.5G or 4.9G. The last two are unofficial buzz-terms used by telco marketers to capitalise on incremental go-faster 4G network upgrades.
The standalone, 5G-only mode (SA) is being prepped for next year, and takes things up a few notches in terms of speed and better responsiveness.
Provided enough people buy 5G devices that use 3.5 GHz, SA actually promises to speed things up for customers with 4G LTE devices as the 900, 1800 and 2100 MHz bands used for the older service will be less crowded.
There's a caveat here: not all 5G modems in smartphones and other devices support both NSA and SA. You may have to swap your NSA compatible smartphone to an SA supporting one in 2020 if bragging rights are important, or hold off with 5G until things settle down.
It will be interesting to see how well the real-life service performs come December.
Currently, Vodafone has 56 MHz of radio frequency spectrum in the 3.5 GHz range, split in two management rights.
That's less than the fat 100 MHz wide channel used for the 5G test environment. Spray said Vodafone's 5G service will launch with a 40 MHz channel. For the telco tech geeks in the audience, the n78 band uses time-division duplexing or TDD, meaning data goes across the same channel down and up, with time slots for receiving and transmitting. That's unlike the 4G LTE service that uses separate frequency bands for downstream and upstream communications.
More spectrum will be added if Vodafone and its new owners spends big in the upcoming government auction next year, but it won't be available for use until 2022.
Ideally, Vodafone, Spark and 2degrees will want at least 100 MHz of 3.5 GHz spectrum each and it looks like the government will put 320 MHz under the hammer.
Finally, despite running at 100 MHz, 5G uploads at Vodafone test setup weren't that impressive at 30-32 megabit/s. That's compared to over 1 Gbps for downloads. Spray said it was due to the test setup at Smales Farm and real-life performance will be different.
December will tell, but fast upload speeds is a big drawcard for early adopters of 5G and Nokia needs to get that right.
If you've made it this far, thinking that 5G is work in progress, you're quite right: it'll take another two-three years before the tech is fully ready to roll.