1. Verizon vs. AT&T isn't TCP/IP vs. TCP/IP. It's more like Token Ring vs. TCP/IP -- the underlying wireless technologies are quite different. Verizon (and most cellular companies) use CDMA for the underlying wireless protocol, while AT&T and T-Mobile use GSM, which (coincidentally) is used most everywhere else on the planet.

2. Since AT&T and T-Mobile use the same wireless protocol, you CAN move phones between the two networks...with some restrictions. For the iPhone, you'd have to jailbreak it first, and you'll lose 3G, but you can still use EDGE-based services for data connectivity, and the phone will still work. The same is true for the T-Mobile G1 Android phone -- you could take an unlocked G1 and run it on AT&T, but you'll lose 3G support. (The reason for this is that T-Mobile and AT&T use different wireless bandwidths for 3G data.)

This is still miles better than Verizon and other CDMA-based cellular providers -- you can't readily move phones between the networks at all.

3. In ~5 years, this won't matter as much, as Verizon has pledged to use 4G for their next generation network (to be deployed in the next 2-5 years). 4G is a GSM-based wireless protocol, so (theoretically) it should be possible to run a 4G iPhone on Verizons network. (Of course, we'll need a 4G iPhone first...) The "big" question will be whether the iPhone will still be locked to AT&T in that timeframe, and whether or not AT&T & Verizon will use compatible wireless bandwidths (i.e. will we avoid the current T-Mobile/AT&T 3G scenario?).

So to answer your question "Are we so primitive in our networking prowess in 2009 that we have to restrict devices to specific carrier networks?" The answer is No. Europe, Asia, and the rest of the world have solved this problem, allowing complete phone portability between networks (with the usual phone tying for the "cheap phones on a 2 year contract" deal we know and love). It's only because the US has (1) multiple incompatible wireless protocols (CDMA vs. GSM), and (2) CDMA has no provisions for phone/network portability that we have any device/network restrictions at all.

Even with GSM companies that tie phones to the network, you can usually unlock the phone after a period of time (except for the iPhone) -- you just need to call up e.g. AT&T and request that they unlock your phone. Then you can go to Europe and purchase a GSM card for cheap local calls...

All good points Jonathan. I know it's not about the overlying protocols. But the overlying protocols should be a thin shim on top of a very portable TCP/IP stack. My real intent (besides ranting) was that Apple would have far better market penetration if they made the iPhone available on all of the networks. The iPhone is sexy enough that it does well in attracting customers to AT&T but the G1 is the one that could really use portability. The T-Mobile network isn't nearly as strong so it seems strange to me that Google opted to tie themselves so closely to one carrier, especially one that's an underdog.

What ever happened to Software Defined Radio? It was all the hype 8 years ago. If all of these devices could adapt their tranceivers dynamically to the radio environment and if we could get the carriers to start acting like infrastructure providers instead of marketing companies...

You get my point. It's an impossible problem, one that government regulation could help solve. But with the way our government has been failing in telecom issues over the past few decades, I'm not sure I want them involved at all.

In an ideal world, abstracting out the network layer would work.  This isn't an ideal world, primarily because of cost: supporting both GSM and CDMA increases costs for testing, validation, and FCC approval (as each phone needs to be tested and approved separately).

(Supporting both networks might not be 100% perfect either; I've heard rumors that phones designed with one network in mind don't tend to work as well when "ported" to the other.  Alas, I have no specific details; this is just what I've heard.)

Cost is particularly important for smaller phone manufacturers, such as the OpenMoko.  Even for larger companies such as Apple and RIM, I'm sure these are important issues -- notice that the Blackberry Storm is exclusive to Verizon for bundled deals.

(I'm also not sure that the iPhone needs greatly improved market, as it's already taken 23% of the market:arstechnica.com/.../iphone-ends-year-with-strong-market-share-faces-challenges)

Then there's the benefits of exclusivity -- reportedly Apple got AT&T to agree to a number of changes that AT&T might not have agreed to w/o the exclusivity, such as Visual Voicemail.  Future iPhone push support will supposedly require additional hardware within the network, so if the network provider (e.g. Verizon) doesn't provide the extra hardware then some iPhone features won't be supported.  Exclusivity provides a carrot for Apple to get what they want from AT&T.  Dropping such exclusivity would lose them the carrot, and thus potentially result in a less compelling product (as e.g. AT&T might not otherwise want to do the extra work).

As for Google and T-Mobile, Google hasn't tied themselves to T-Mobile.  They're trying to pull a Microsoft -- they'll provide the operating system (Android) and work with hardware providers for the actual phone.  The G1 is supposed to be the first of many Android phones, and I don't know of any reason that Verizon couldn't be supported (except hardware vendors not wanting to pay the associated costs, mentioned above).

Finally, the software defined radio died because of the government; government can't save it.  It died because it would allow things that governments don't like, e.g. allowing consumer-grade devices to capture military communications.  Most governments don't like that, and unless you somehow restrict the hardware from listening in on the military channels the goverment won't approve.  Alas, such restrictions are anathema to the entire idea of software defined radio.  So at present, the best we're likely to see is software defined radio as an implementation, but the utility/flexibility wouldn't be exposed to "userspace" applications; the restrictions would be "baked" into the firmware.

If the rumors are to be believed, Apple first went to other phone companies before AT&T with hopes of getting the iPhone off the ground. With the original iPhones Apple had a huge list of demands, including not having to activate the phone is a store, selling the iPhone from an Apple store, the carrier had to integrate the visual voicemail etc... and Apple didn't want any contracts. AT&T was the only company that would relent to Apples demand because they felt like they had the most to gain from the recent Cingular merger. Apple and AT&T signed a 5 year contract, and voila, you have a single company phone. Who knows if all of the rumors were true though, but it sure seems to make sense.

That's more or less what I heard.  I hadn't heard about the "no contract" part, and that doesn't even make sense considering that they signed a 5 year contract (unless the contract was for something else?), but I had heard about the various demands including Visual Voicemail.

It's because of demands like that, and cooperation from the phone company, that the iPhone is as compelling as it is.  Apple is likely to continue this further (e.g. the aforementioned "push" functionality).  So making a "generic works with every phone company" phone likely isn't in the cards, as Apple is all about the vertical integration.  This has it's good points and bad points.

But as long as not all customers require the vertical integration, it should be possible to move phones between networks.  And it is -- you can jailbreak the iPhone and run it on T-Mobile, for instance, and overseas networks.  The only loss here is Verizon and other CDMA networks, but even that will (hopefully) disappear with the migration to 4G...

Indeed, it appears as though Apple's eye for user experience (not just GUI) has begun to transform the mobile phone market. The process of buying and activating the iPhone was impressive, in a good way. I wonder at which percentage of marketshare will Apple be accused of predatory practices to get as far as they have? I ask that half jokingly. Microsoft has been punished for its hard work by the EU for a decade now.

By the way, although it's expensive, you can buy unlocked "developer" version of Google Phone and make it work in AT&T. I did just that, because I couldn't wait any more. It was easy with a help I got from Android Google group. Android is quite interesting programming environment (with Java or even Scala used for developing custom application). A developer's community there is very active. Look at http://developer.android.com/index.html, developer.android.com/guide/developing/device.html
You'll have to register as Android developer (http://market.android.com/publish/Home) and then you'll be able to buy a phone.