AT&T tells consumers to change their phones since they will stop working

[Kisai]

2 hours ago, gabrielcarvfer said:

That is a very interesting way to describe CDMA. It doesn't have a way to allocate "bandwidth"(resources)? I'm pretty much an ignorant on how the devil SS works, but I thought you could assign multiple codes to a single user to let it transmit more data.

*Me reading "MSC" and trying to figure out where that kind of functionality would map onto LTE entities. I need to make some 3GPP bingo cards.*

Trust me, training materials for GSM was full of acronyms and conflicting information from marketing. 

 

By evolving the technology each "cell" can hold more customers. The MSC is where your "phone numbers" and billing information is stored, so it's responsible for tracking everything.

 

Reference if you need it:

http://web.ncyu.edu.tw/~sheng/912/pcs/Introduction.pdf

 

So with AMPS (1G, or IS54), one cell could serve only as many customers as it was sectorized, so in mountainous areas you needed a lot of them below the tree line, because one cell site could "serve" the entire valley, but it would only have the capacity for X many users that the carrier had bandwidth for. Since all American carriers basically started as AT&T, they all evolved from the same 1G tech. So how to tell if you had a 1G or 2G phone, is if it had an ESN number. The ESN is what the cell network used to authorize devices, othewise people could just listen in. But it's wasn't magic. So one MSC could serve an entire NPA-NXX, but the actual capacity of the cell sector was 333 users So divide a cell into three directions and you instantly had 999 users capacity in radio bandwidth but then had no way of handing them over.

 

Reference if you need it

http://web.ncyu.edu.tw/~sheng/912/pcs/chap5.pdf (TDMA)

http://web.ncyu.edu.tw/~sheng/912/pcs/chap6.pdf (CDMA)

 

In 2G, D-PCS (TDMA and CDMA in the US, formally known as IS136 (TDMA) and Is-95(cdmaOne)) divides up the analog channels into more efficient Time-division (time slots) or Code-division, as described earlier. In 2G GSM (as rolled out in Europe), is a TDMA technology but not the same TDMA as IS136. The unique thing about GSM is the SIM card, which made it dramatically cheaper to switch phones, until carriers started carrier-locking the phones anyway.

 

Anyway CDMA capacity:

 

 

 

GSM: http://web.ncyu.edu.tw/~sheng/912/pcs/chap7.pdf

 

A lot of information on the internet that doesn't come from technical sources is wrong, because companies like AT&T, Verizon and T-mobile marketing drones called their 2G GSM networks "2.5G" or 2.75G" or even "3G" when they were in fact, still, 2G networks. They were just 2G networks using a different technology. In fact CDMA was more spectrum efficient than TDMA, and TDMA was more efficient than GSM, as far as 2G tech goes. GSM's selling point was the decoupling the subscriber account from the physical device. So if we are being as nitpicky as possible AT&T had two separate 2G networks, the IS54/IS136 TDMA network, and the GSM network.

 

The tech people know what is what. The sales people were clueless, didn't care how the cell network worked, often sold garbage devices for high commissions, and the customer care people often only dealt with voicemail resets and programming the 2G phones. Everything else was billing and completely decoupled from how anything worked unless you regularly had to speak to the actual network technicians, and they absolutely won't talk to sales or even the customer. In one of the internal training docs at AT&T wireless circa 2004 they said that 70% of their sales comes from third parties and, and so did the phantom churn. Local Number Portability pretty much spelled the end of phantom churn since you couldn't port your number to the same carrier.

 

Bane of my existence during the TDMA network was the Motorola V60i, the most fragile phone on the planet. Even more fragile than all-glass smartphones. When I worked the WEX queue (that's warranty exchange) that was after the GSM migration was in full force, and guess what phones people were calling in to replace? The free garbage phones from LG and Samsung. To this day I will not consider buying phones from LG or Samsung, and have strong reservations about buying anything with their brand names.

 

Anyway moving on to UMTS this was rolling out while I still worked for AT&T Wireless, and subsequent purchase by Cingular. So I've read the materials on it, but never encountered a customer with a device while I was there.

http://www.tti.unipa.it/~ilenia/course/13-umts-core.pdf

 

In LTE, the MME basically does the same thing the MSC does in the 2G network.

 

But since data and voice are technically different services, (except VoLTE, which is voice over the data network), they are two separate things tracking your usage, one for the data (internet) and one for the voice network. Then there's also all the various kinds of APN's that can be setup.

 

Which circles back to the question about falling back to 2G or 3G. They do this, as far as I know by manipulating the "internet APN" for the high speed bandwidth so the device falls back to the slower 3G or 2G WAP APN, even over the 4G LTE network. Historically, the "WAP" APN was for basically RSS feeds and WAP websites. This later changed with smartphones as sites like facebook and twitter just made HTML5 sites and thus whatever compression and optimization needed for the WAP site, was irrelevant. But the WAP APN is typically the slow path. The Internet APN is usually the fast path, but also the one that carriers like AT&T would charge you extra to use because it was seen as tethered data, even though it was no different from using the data on the device itself.

 

There really are cases where the carrier basically tried to charge more for LTE, or 3G when people had phones that were capable of LTE/3G/2G-GSM or 3G/2G-GSM, and with every technology upgrade you see the same scam again, where the carrier tries to charge you more, for the same access.

 

So the next time you ask "why am I paying for 20GB of premium data on top of unlimited", ask what does the carrier gain from doing that. Because really, what they did is raised the price, and then got rid of the bandwidth costs, because they likely cost more to dispute with customers than they actually gained. See also landlines how we originally had unmetered bandwidth, and then the caps came in because of napster/kazaa/bittorrent, and then the caps started going away when the companies who owned the content realized nobody will pay for their content if they have to pay for data to access it.

 

So that's why you're seeing unlimited data on mobile now, they now want you to watch the content they own , and can do that by favoring their own content and slowing down the competition. Remember Net Neutrality. This is what it was designed to avoid.

 

[Kisai]

12 minutes ago, gabrielcarvfer said:

Doesn't talk about the physical layer/channel itself. My point was that the users receive a code mask which is used along with the spreading factor to transmit the encoded bitstream. The same code masks are then used to separate and decode each of the different streams transmitted in a single channel and at the exact same time. If you have capable hardware, I think you can give multiple codes to a single user allowing it to transmit multiple streams simultaneously, effectively giving him more radio resources (not exactly bandwidth nor a time slot).

With LTE, the send and receive channels are separate. That's about the extent of it. Since the technoligy is resiliant to interferance basically if you are the only person in the cell sector, you theroetically have 100% of the sector's bandwidth to yourself. So early adopters of UMTS, LTE and now 5G have seen this where the networks start out fast, but over time they get so congested that the "up to" part of "up to xxxMbits!" lines start feeling like mockery. 100,000 people in a convention center are not going to be able to share 1gbit, no matter how the carrier wants to frame it. What UMTS promised were picocells for places like convention centers and transit tunnels, and those never happened because, gee the carrier doesn't want to pay the property owner for access.

 

12 minutes ago, gabrielcarvfer said:

Not sure how antenna legislation works on where you live, but in Brazil it is a huge mess (a ton of municipalities have different legislation limiting installation sites, compensation costs, height restrictions, number of antennas, etc) causing an insane deficit of antennas. Partially explains why there are data caps/bandwidth limits (statistically reduces the load on the network).

US and Canada have similar issues, the more dense the area, the more restrictive it gets, antenna's are usually on 5-20 story buildings, and no higher here. Like I can go outside and go to the end of my block and see the antenna's for one carrier on the corner of a building, and then turn around and look at the taller building one block over and see the antennas for another carrier.

 

12 minutes ago, gabrielcarvfer said:

Which partially makes sense, if they have the caches closed to the towers and can reduce core traffic. It indeed is unfair with competing services, but my carrier offers a ton of stuff on top of the data (Deezer and Skeelo premium subscriptions for music and ebooks, plus a subscription that provides access to major newspapers and magazines).

 

Yeah, I don't fault the carriers for wanting to save bandwidth costs by having edge caching, but really they, own their backhaul, especially Verizon and AT&T Wireless. Like during the 3G deployment, they had a marketing celebration of finally switching to using all their own backhaul network so it no longer cost them money from AT&T (the wireline company whom they were split from at the time.) 

 

Anyway, as far as bandwidth goes, it's not the cell phone bandwidth that is being throttled, it's the QoS in the base station saying to limit how much to send to the mobile device, and it's completely arbitrary. It costs the carrier nothing, so "premium" bandwidth is fictitious.

[Kisai]

11 minutes ago, Hakemon said:

Then you must be lying, because I swear I'm using 2G right now here in the US.  This phone is running on the 1900MHz PCS band, using 2G GSM service right this very second.  And has been when I travelled from Florida to Massachusetts with no drop in service whatsoever except one highway.

Flip it over and pull the battery out, I'm 100% sure that is a 2G GSM phone. T-Mobile never had a 2G TDMA network, and those were all sunset in February 18th 2008.

 

What you are in fact using is T-mobile's 2G GSM, which for marketing reasons is also called the 3G network, for the same reason AT&T called their 2G GSM network 3G.

 

Remember my argument here is that marketing is outright lies.

https://www.multitech.com/documents/publications/marketing-guides/MT_Anticipated_Sunset_Cellular_Carriers_PDF.pdf

 

AT&T had two 2G networks, one was AMPS/TDMA the other was GSM. T-mobile only ever had the GSM system under "T-mobile", so it was impossible to have had a 2G TDMA system, because T-mobile wasn't T-mobile then. That was Voicestream which was spun off Western Wireless, which was started as GSM.

 

[Donut417]

6 minutes ago, Kisai said:

What you are in fact using is T-mobile's 2G GSM, which for marketing reasons is also called the 3G network, for the same reason AT&T called their 2G GSM network 3G.

3G (UMTS/HSPA)

• Frequencies that can provide 3G: Band 4 (1700/2100 MHz) and Band 2 (1900 MHz)
• Voice and data services can work at the same time. You can use data while on a call.

2G (GSM, GPRS, EDGE)

• Frequencies that can provide 2G: Band 2 (1900 MHz)
• Voice and data services don't work at the same time when on 2G. You cannot use data while on a call.

https://www.t-mobile.com/support/coverage/t-mobile-network

 

Then you know something T Mobile doesn't. Because they clearly list out 2G and 3G. While both seem to use band 2, specifically T Mobile states that 2G can not do calls and data at the same time, while 3G can. They further go on to show which networking techs they use for each. 2G being GSM, GPRS, and Edge. While 3G is UMTS/HSPA. 

[Kisai]

32 minutes ago, Donut417 said:

3G (UMTS/HSPA)

• Frequencies that can provide 3G: Band 4 (1700/2100 MHz) and Band 2 (1900 MHz)
• Voice and data services can work at the same time. You can use data while on a call.

2G (GSM, GPRS, EDGE)

• Frequencies that can provide 2G: Band 2 (1900 MHz)
• Voice and data services don't work at the same time when on 2G. You cannot use data while on a call.

https://www.t-mobile.com/support/coverage/t-mobile-network

 

Then you know something T Mobile doesn't. Because they clearly list out 2G and 3G. While both seem to use band 2, specifically T Mobile states that 2G can not do calls and data at the same time, while 3G can. They further go on to show which networking techs they use for each. 2G being GSM, GPRS, and Edge. While 3G is UMTS/HSPA. 

Go back up and look at the screenshot from AT&T calling their GSM network 3G, when it wasn't. T-mobile can, and has, called their 3G network, 4G, just to say they had 4G when they didn't. What the carrier calls their network is just marketing to trick you.

 

So once again:

Verizon operated a 1G/2G/3G network based on CDMA, what they are sunsetting is this network. The LTE is a new build and they can not shut their old network down until all markets support VoLTE. Verizon sunset their real 2G network in 2008.

AT&T operated both a 1G/2G network based on TDMA, and a 2G network based on GSM designed to be upgraded to 3G WCDMA from inception. The LTE network is a further upgrade of the UMTS 3G WCDMA network. So when AT&T is talking about sunsetting, the 2G network now, they are talking about the 2G GSM network, not the 2G TDMA network which was shutdown in 2008.

T-Mobile has only ever operated a 2G network based on GSM, that network, just like AT&T can be upgraded to 3G WCDMA, and then to LTE. However they are the oldest 2G network operator. They also have never operated a anything in the US marketed as a 2G network except retroactively.

Sprint operated a 1G/2G/3G network based on CDMA and when they acquired Nextel they shut down Nextel's network in favor of their own, and when T-mobile acquired Sprint, so this is the point point where you could technically say T-mobile owns a 2G non-GSM network, but not for very long, as Sprint had been rolling out LTE for as long as Verizon has, and has the exact same upgrade path. I fully expect this will just accelerate the decomissioning of Sprint's 2G/3G CDMA network and Sprint customers will not be offered upgrade options except to T-mobile's 5G devices.

 

Part of "switching" to 3G or LTE, or 5G is frequency harvesting, which means that in 2004 T-mobile might have had 100% GSM coverage on 1900Mhz, but in 2020 they might only have 5%, to cover the remaining 2G customers, and your coverage is likely only on the 1900Mhz band. Since T-mobile never operated 2G IS-95/IS-136 on 1900Mhz, they didn't have to do that with their 2G GSM network.

 

For all intents, in the US, the "GSM" network has been marketed as both 2G and 3G, but it's 2G. When you see news items talking about 2G networks, they are talking about IS-95 (Verizon/Sprint) and AT&T/T-Mobile's 2G GSM/EDGE networks. When they are talking about 3G, they are still talking about Verizon/Sprint's IS-95 CDMA network, but they are talking about the UMTS network for AT&T and T-mobile, which both carriers have called 4G at some point in time.

 

https://www.att.com/support/article/wireless/KM1008736/

Quote

List of areas currently not supporting 4G LTE speeds for devices listed above

If you’re in one of these areas and using a device listed above, your device will only reach 4G HSPA+ data speeds.

 

the only defining feature of "4G" as far as US carriers are concerned is the downlink speed. Not the technology. This retroactively applies to 3G and 2G.

https://appleinsider.com/articles/12/02/21/qualcomm_releases_new_gobi_universal_mobile_chips_with_lte_support

 

https://www.parts-people.com/blog/2012/01/27/4g-imt-advanced-lte-wimax-vs-3g-speed-executive-summary/

 

You have 2G/3G/4G "marketing" and then you have 2G/3G/4G as defined standards. There is no defined standard for 2G, only retoactively. Because at the time DPCS CDMA and TDMA were released they were simply called "Digital". You know, as opposed to Analog.

[Kisai]

39 minutes ago, Hakemon said:

 

Can you please make up your mind?

 

Also it's funny you embedded a graphic which clearly shows 3G as containing HSPDA, etc, and 4G as LTE.  Now, when I worked at Apple when the 4S was released, why exactly did AT&T request us to change the 3G indicator at the top to say 4G when it was on HSPA?  It wasn't just T-Mobile that did this, AT&T did as well, because I remember when it was requested to be changed for your marketing purposes.

Because the circular argument here is being made by people who are asking bad faith questions. They know I'm right, they just don't understand what is being discussed, and it's pretty clear that even the dude who claimed to work for a third party dealer didn't know what he was talking about either when I replied to him, which is what you are quoting out of context.

 

This:

Quote

1. 2G in the US was TDMA and CDMA. Which was called Digital PCS or D-AMPS. It was  backwards compatible with AMPS on those devices. That is not wrong.

2. 2G is not in use by any carrier in the US. 

 

is in response to:

Quote

Holy moly this is very wrong.

 

1. 2G in the US is absolutely digital. 
2. 2G is still in use by some carriers here and in 2009 all 4 major carriers still had it.

To which I had to then dig out the FCC document showing the Feb 18th 2008 shutdown date. So for AT&T's TDMA and Verizon's cdmaOne network that both supported AMPS, those went down, because those were the 2G networks that were married to AMPS. I made no mention of T-mobile here. So I continued:

Quote

3.  Absolutely Wrong. GPRS is 2G, EDGE was 2.5G (phones display E), UMTS was 3G. HSDPA was 3.5G (or remarked as 4G, but was not 4G)

4. No, from the horses mouth, again

https://scache.vzw.com/dam/businessportal/content/assets/files/Rev_A_WP.pdf

cdmaOne - 2G

CDMA2000 - "3G"

CDMA 1xEV-DO, rev 0

CDMA 1xEV-DO, rev A

 

This is what happens when customers and sales people do not know what they are talking about and get confused by marketing and software tricks. So devices from AT&T would say you were on 3G even when they weren't on UMTS, when you weren't. Devices from both T-mobile and AT&T would say they were on 4G, even when they were not on LTE.

 

If you go entirely by the 3GPP definitions, GPRS and EDGE (both part of GSM) were not 3G, and were never 3G. 3GPP also defines HSPDA and HSUPA as 3G, not 4G.

 

So if you haven't figured it out yet, and I've said it in the last few replies in this thread. Y'all confusing marketing for standards. Your average news site is not a tech site and doesn't care. So when you see AT&T shutting down their 2G network for a second time, you know the news site hasn't even done the minimum of research. Likewise you will keep seeing "X carrier is shutting down their 3G" network for the next 5 years because they're all due to be shut down by 2025.

https://www.digi.com/blog/post/upcoming-2g-and-3g-global-cellular-network-sunset

 

So you see why AT&T and T-Mobile's don't make sense? Because AT&T didn't start calling their 2G GSM network except retroactively. T-mobile didn't call their 2G GSM network 2G except retroactively. Why would T-mobile shut down their 2G network in 2020 and AT&T shut down their 3G in 2021 if it wasn't for the fact they were talking about the same network technology.

 

So at the end of this year, there should be no 2G networks in operation other than the legacy Sprint network. At the end of next year, the voice part of the AT&T 3G network will be shut down, hence the reason for the handset changes (see the first page of this thread.) Likewise with T-mobile, which made the same announcement.

https://www.androidpolice.com/2020/07/25/t-mobile-will-soon-require-volte-on-all-phones-incomopatible-devices-kicked-off-january/

 

 

Notice they're not accepting 3G devices? That means they are sunsetting their 3G network in 2021. Your 2G GSM phone stops working this December, and any 3G devices likely will stop working the following year, as it has to be done in tandem with AT&T otherwise the carriers lose each others coverage areas.

 

You're also likely to see a story next year of T-mobile shutting down their 2G network a second time when they are really talking about the Sprint network.

[ryao]

On 7/23/2020 at 4:24 PM, Kisai said:

Very wrong. T-Mobile did not have a 2G network, at least not by the marketing used in the US.

 

But this requires re-framing the entire "2G, 3G" problem.

 

Verizon (then GTE), AT&T, US Cellular, Cingular, Sprint, Nextel, Alltel and so forth's "2G" networks were all AMPS (Analog, 1G)-compatible networks. So all the predecessor networks were AT&T and whoever was "B side" spectrum. AT&T had half (A carriers), other local carriers (B carriers) had the rest (I'm recalling information that is very obsolete, so don't nitpick this.) This was all 850Mhz spectrum.

 

In 1984 AT&T was broken up, and some fun things happened. It resulted in several fragmented 2G networks.

 

D-AMPS aka PCS was all 1900Mhz spectum. This split into TDMA (AT&T, Western Wireless(T-mobile as Voicestream), Cellular One (Cingular)) and CDMA (Western Wireless(Cellular One), Verizon, Sprint, Alltel), with Nextel using an entirely different incompatible system called iDEN. All of these 2G networks were shutdown by the end of 2009.

 

For all intents, all 2G service in the United States and Canada ended in 2009. However what is called 3G in North America (GSM) is actually 2G in Europe.

 

AT&T's "3G" network was GSM-EDGE, and really it was 2.5G in internal systems. UMTS was the 3G network. So you had some phones that would say 2.5G, some would say EDGE, some would say 3G, and some would say 3.5G depending if they were using the GSM voice mode or EDGE(2.5G)/HSPDA(3.5G) data features. GPRS(2G) was supported but pretty much unused by the GSM devices as most devices at the time did not have bluetooth, and devices required tethering to use GPRS and it was slower than dialup. EDGE wasn't that much of an improvement. 

 

LTE is 4G. LTE-Advanced, is also... 4G

 

Devices that support LTE/LTE-Advanced also have GSM/UMTS/HSPDA radios in them and can not simultaneously use them. This is also why Verizon models that used the CDMA2000/1X voice mode, can not simultaneously use voice and data. Only LTE where VoLTE is supported can do that as only one radio is needed. CDMA2000/1X support requires two entire radio stacks in the chip and additional power amplifiers. As it is, most CDMA2000 cell phones do not support the AMPS mode anyway, as there hasn't been an AMPS network to connect to in 10 years.

 

So when Verizon and Sprint shut down their "2G" networks, they are really talking about their AMPS/D-PCS compatible networks, but those were running their own "3G" tech that has nothing to do with GSM 3G. Verizon is shutting down their CDMA2000 network this year, Sprint is still in the process of migrating things to T-mobile, but the same would be expected by next year.

 

This is why AT&T and T-Mobile shutting down their "legacy" networks, the 3G GSM networks is going to be a thing in the next 2 years as well. By the end of 2022 there should only be LTE/LTE-advanced networks in north America, and we will finally be back to one standard like it was in 1983.

 

T-Mobile started as GSM, so by US definitions, it started as a 3G network, under the brand Voicestream, which was later acquired by T-Mobile (Germany.) This also kinda hobbled it since GSM devices could not use the D-PCS or AMPS networks. 

 

The relationship between all the pre-4G carriers and each other is complicated as there's basically a babybell explosion in 1984, followed by multiple independant cellular networks before they all started merging with each other.

 

Verizon and AT&T are the surviving companies of the baby bells and their wireless ventures merging. 5 of the 7 became AT&T again. 1 of the 7 became Verizon, and the last one is CenturyLink which is actually a major internet backhaul carrier and didn't venture into wireless.

 

While we're at it, for completeness. 

Bell Canada hadn't been a part of the "bell system" for decades before the breakup, and thus was independant of goings on in the USA. Bell operates the Central/Atlantic Canada wireline and wireless

 

GTE (Verizon) owned investments in BCTel in Canada, prior to the breakup of the US Bell system, and references to GTE can still be found in pre-Telus documentation. BC Cellular was an early AMPS network. 

GTE created Sprint but had to operate it independently.

 

Rogers Wireless was previously known as Cantel AT&T, and previously just Cantel. AT&T owned part of Cantel at the time before Rogers bought it out. Rogers Wireless (as Cantel) operated 2G TDMA and GSM 2G networks.

 

BellSouth (BellSouth Mobility) and SBC (which had Cellular One) created Cingular One out of their previous AT&T spectrum assets, on GSM.

 

So what was sometimes called a 2G network on one carrier was a 3G network on another. Even some pre-LTE stuff that AT&T and T-Mobile engaged in called their 3.5G networks 4G. They also did this with 5G and had their arm twisted to not do it.

 

So AT&T has announced their 5G network now. Like literately today. Available August 7th.

https://www.theverge.com/2020/7/23/21335456/att-5g-network-nationwide-verizon-hbomax-warner-date

 

Like literately, Verizon and AT&T were renaming their LTE service to 5G and just going "whatever"

 

As far as I am concerned, GSM is 2G.