What actually determines whether I see H+ or 4G in the top panel?

Question

So, I read the answers to What are the different signal indicators avalable on the notification bar? and as one answer says:

• 3G: UMTS (384 kbit/s to 7.2 Mbit/s)
• H: HSPA (enhanced 3G, sometimes shown as 3.5G; up to 21 Mbit/s)
• H+: HSPA+ (even more enhanced/faster HSPA; up to 42.2 Mbit/s)
• 4G: LTE (thanks to eldarerathis for confirmation); up to 300 Mbit/s

I'm guessing that these speed definitions are determined by some international convention or something like that.

I have different SIM cards from different carriers.

When I use Carrier A I see H+, H or 3G in the panel. I get speeds ranging from 4 to 12 megabits per second.

When i use Carrier B I always see 4G in the panel. However, I get speeds ranging from 1 to 2 megabits per second.

By the way, these are general trends for these carriers in various areas, not isolated instances of speed.

So, it seems that what symbol I see in the panel needs not matter so much for the actual speed? (Except for E, which is always terrible regardless.)

If not speed, what is the real reason for what symbol I see? Is it arbitrarily set by the carrier? Can they simply choose to call their network whatever they like? Or does it have to do with what sort of technology they have in their tower? Maybe Carrier B actually does have 4G towers, only their networks are overloaded and therefore cannot supply proper speeds to all the users?

I am in India where 4G is still new. AFAIK, Carrier B might have more traffic than their network can handle.

Answer 1

• It is the speed that determines what is shown in the indicator

• For the conventions regarding the symbols and speed , see this - which are in line with what is mentioned in your question

• Advertised throughput speeds are not the actual, real world throughput speeds experienced by the end user. See this for factors affecting the speed

Coming to your main concern regarding different speeds and variance with symbols displayed:

Situation described is India specific and regulated by Telecom Regulatory Authority of India. AFAIK, they are aware of operators delivering lesser speed than advertised and are in the process of streamlining it. Details are being skipped here being broad / opinionated

• Operators are not at liberty to falsify speeds - some typical practices have been covered in comments

• It is best to reach out to the carriers and or TRAI to get to the operator version of it

Answer 2

The speed has nothing to do with the icon being displayed so that statement is incorrect, the icon is specifying what technology is being used to connect to the mobile network. The handset is not evaluating performance and making a judgement about the icon. A slow 4G connection will still show 4G.

4G has much higher theoretical speeds and therefore should in general be significantly faster. However, numerous other factors will affect overall performance, such as:

• Signal strength (a 1-bar 4G may be worse than a full-bar 3G connection for example)
• Traffic shaping at the carrier or other restrictions
• Contention or other back-end infrastructure performance issue at the carrier
• Local network performance e.g. mast equipment at the carrier

If you've got a 4G-capable carrier that is performing worse on a like-for-like basis than a 3G+ carrier then this is of course a significant problem but it is a carrier problem nonetheless.