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This is a rather general question about hardware and standards in general:

Why do they place limits on data transfer rates, and disallow manufacturers from exceeding those rates? (E.g. 100 Mbit/s for Wireless G, 150 Mbit/s for Wireless N, ...)

Why not allow for some sort of handshake protocol, whereby the devices being connected agree upon the maximum throughput that they each support, and use that value instead? Why does there have to be a hard-coded limit, which would require a new standard for every single improvement to a data rate?

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Unless we can get someone in here that helped draft the standards, there's no way to get a factual answer to this and also as per the FAQ, "You should only ask practical, answerable questions based on actual problems that you face", but you are asking for opinion on a standard, not help to resolve a problem with your hardware or software. –  Linker3000 Jun 25 '11 at 7:56
    
@Linker3000: I was just having a discussion with a mod about this (both meta and chat); the question was reopened. If the answers or comments get off-topic or unconstructive, then by all means, I'll vote/flag to close it myself. But we think it might be a good idea to give it a chance and see if anyone has a good answer, since I think we could get potentially good results if some people are familiar with this -- I think it's a rather obvious question about very familiar technologies (USB/SATA/WiFi/etc.) and people might like to know the answer. –  Mehrdad Jun 25 '11 at 7:58
    
I admire your optimism ;-) I could answer the question (I am an electronics engineer), but I feel that although the info would be perhaps of transient interest, it would have limited practical, ongoing use to the broad audience here. –  Linker3000 Jun 25 '11 at 8:03
    
@Linker3000: Lol thanks xD –  Mehrdad Jun 25 '11 at 8:03
    
I think this question is too broad to answer in a satisfactory manner. The reasons for different data speeds for different technologies vary to greatly. –  Flimzy Jun 25 '11 at 8:26

3 Answers 3

In general, when a new communications technology is invented, the inventors make it as fast as possible. They don't know any feasible way to economically make it faster. They set a speed at which the technology should operate so that users can be sure that equipment from different manufacturers will interoperate.

Take Ethernet as an example, after playing around with lower speeds, the group that defined the standard settled on 10 Mbps over thick coaxial cable. If they'd known then how to get 10 Gbps over twisted pair cable at a marketable price, I'm sure they would have done it.

If you've worked out how to get 10Mbps over thick coaxial cable, you probably don't know how you could get 10 Gbps over the same cable and it would be pointless specifying how all the nodes should negotiate speed if you don't yet know how future high speed devices might interoperate with low speed devices.

A kind of exception exists for low-speed low cost systems such as USB. It was known the keyboards need lower IO rates than memory devices so they built in a way to negotiate between low and high speeds. Yet even higher speeds had to be retrofitted - they were not anticipated in the original standards. It is better to issue a usable standard now than wait until you can work out what speeds might be possible in twenty or thirty years time.

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In general one of the advantages of a standard is, that with adaptors supporting a certain standard, and cables supporting a specific standard, it will work. With that in mind, most IEEE standards tend to be conservative, slightly overenginnered, and will generally work as advertised.

There's nothing stopping a manufacturer from extending the standard to increasespeed - which in this case wasn't always as advertised - or to use a non standard speed or interface. By following a standard, manufacturers ensure that their products, when bought, arn't returned cause they are incompatable.

There's nothing forcing this - standards make sense for everyone involved, since it means all gear conforming to a standard will work together, and you don't need to worry about whether gear from company A and B support different, non-compatable approaches - one reason you can use a ethernet interface (10mbps) with any sort of ethernet cable, and they can co-exist with fast ethernet (100mbps) and gig-e (1gbps) adaptors to an extent.

Its just like networking - there's nothing stopping someone from running an alternate domain system, or replacing HTTP with a different protocol. The standards just make it simpler for everyone involved.

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The point of standards is to insure interoperability of devices that conform.

If I manufacture a FooStand v2 device that actually emits data 20% faster than FooStand v2 devices are required to accept it that breaks the interoperability guarantee. Which is bad.

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