Originally Posted By: KateSorensen
Recently I found another article that talked about Apple, AT&T and 4G. It was very interesting and I understood some of it. Looks like I have HSPA+ [what ya think, Reboot?
Okay, you asked for the time, let me see if I can do it without trying to explain how to build a clock. smirk If you get bored, the last 5 paragraphs below the stars will probably tell what you asked about. The rest is for anyone interested in a plain english explanation of some terms we hear a lot about.

At one time 4G LTE was the only network allowed to be called 4G. Sprint and Verizon had to go to 4G LTE as their CDMA network was maxed out for speed and functionality whereas others like T-Mobile and ATT still had a lot of room to move with their GSM networks.

The difference between GSM and CDMA is for example GSM is a highway with multiple lanes many separate cars (one passenger per car) can use at the same time and exit when they want, or make turns, (hopping to a different cell tower) without slowing each other down. The GSM highway can make narrower lanes so that there are more lanes just by painting new stripes and the cars can be made faster easily, so thus they can be expanded to carry more people (calls) on the same width of highway and at a greater speed. (HSPA+)

CDMA is only a one lane highway, and uses a bus to carry a lot of people in the same direction at once. That sounds good, carrying more people at once, but each time the bus gets to a turn (a cell tower) it has to stop so passengers can get off and on the bus, instead of a straight shot to the destination like the cars (GSM) have.

Unfortunately the design of the on and off ramps and bus depots of the CDMA highway were not made for expandability so they are at their limit, and the busses couldn't be any bigger either as the roads can't handle it. That's why Verizon had to be the first to build a new expandable LTE highway right next to the old CDMA highway (on the same cell towers.)

Upgrading either a CDMA or GSM network to LTE requires new hardware. In order not have to spend a lot of money at once to upgrade their network to LTE, ATT employed 3G HSPA+ on their networks (my expanding highway explanation) which only involves software (painting new stripes and souping up the cars) on the carrier's end. Of course the receiving hardware has to be able to do HSPA+, the iPhone 4S and the new iPads do. HSPA+ is a stop gap for ATT on their conversion to 4G LTE. HSPA+ speeds come close to current LTE speeds and are a big improvement over HSPA.

Verizon had no choice but to invest in new hardware as their network speed was at its max.

LTE is supposed to be the answer for dropped calls eventually. Currently though LTE is only used for data by all carriers, and the voice is over CDMA or GSM.


Okay, so what's this 4G, 3G, HSPA+, LTE confusion. It's not our fault, it's marketing and floating "standards." 4G is a standard to define network speed, set up by The International Telecommunications Union, ITU. It's not not any particular technology, GSM or whatever. The G stands for generation.

At one time only LTE met the original ITU 4G standard. Once HSPA+ speeds were announced they were much better than HSPA, and closer to LTE speeds. So the ITU requirements to call a network 4G were ignored by the carriers to sell phones and plans, and eventually the ITU caved and set the bar lower.

We now have 4G HSPA+ and 4G LTE whereas it used to be 3G HSPA+ and 4G LTE. Just a name change.

Your "first layer" of 4G is HSPA+, the next "layer" will be LTE. "Layer" is just a name some marketing genius came up with to make the fact that they're not upgrading the network to LTE yet sound better.

So they basically changed the rules as to what they can call 4G without telling anybody. crazy

And that's how you build a clock. grin