WM Team Blog: "Why Did We Remove Bluetooth DUN?"

[Janak Parekh]

<div class='os_post_top_link'><a href='http://blogs.msdn.com/windowsmobile/archive/2007/04/17/why-did-we-remove-bluetooth-dun.aspx' target='_blank'>http://blogs.msdn.com/windowsmobile...etooth-dun.aspx</a><br /><br /></div><i>"I'm Greg Scott and I work as a developer on a team that provides core networking technologies on Windows Mobile. There has been some [negative] feedback from the community about Bluetooth dial-up networking (DUN) being removed in WM5 AKU3. I'll do my best to explain that."</i><br /><br />A good article from Greg as to why we should look <b>forward</b> to Bluetooth PAN devices. Ironically, just as they're readding DUN back to WM6, Apple's newest OS release, 10.4.9, adds PAN to its Bluetooth stack, so one of the major reasons to reintroduce it is gone. Personally, I think PAN is the way of the future -- but, in general, it's always better to accommodate your users and gradually remove technologies, as opposed to the complete switch made in WM5 AKU3. (Oh, and note to Microsoft: I'd <b>love</b> to use PAN, but Palm never released AKU3 for my 700w. :roll:)

[Chris Spera]

...(Oh, and note to Microsoft: I'd love to use PAN, but Palm never released AKU3 for my 700w. :roll:)

...and I don't know that you'd WANT to use PAN on a 700w. With its limited amount of memory, its so poor, it can't afford to pay attention. Besides, I don't think VzW would even let you use PAN to communicate with non-VzW devices on their network. They won't let you use DUN (without paying an extra fee...right? Its been a few years since I was a VzW customer, so I can't remember if they implemented that fee or not) on their network.

[Menneisyys]

Crossposting my post I've sent there:

"First, thanks for the article - it explained a lot. This question has been bugging me (along with a lot of other WinMob users) right from the introduction of AKU3 and this is why I've written a full overview &amp; comparison of the new model on the Pocket PC Magazine Expert Blog at http://www.pocketpcmag.com/blogs/index.php?blog=3&amp;p=1415&amp;more=1&amp;c=1&amp;tb=1&amp;pb=1 (also frontpaged by Pocket PC Thoughts).

It's also nice to know cell phone rebranders / manufacturers could include DUN if they wanted to. You should consider *forcing* them to include it as the lack of DUN is, in my opinion, decidedly a problem.

However, there are some things in the article I disagree with.

1. You state "Bluetooth DUN is a legacy technology that is likely to disappear over time. Especially when you look at the great experience Internet Sharing provides with Bluetooth PAN. It also does not make sense for cellular radios to continue supporting a legacy interface just to enable Bluetooth DUN. In the past we received a lot of criticism about Modem Link, especially related to usability. For this reason we decided not to include it by default."

I'd add that you don't need Modem Link (see for example my related DUN tutorials - for example the one at http://www.pocketpcmag.com/blogs/index.php?blog=3&amp;p=510&amp;more=1&amp;c=1&amp;tb=1&amp;pb=1 ) for internet dial-up. This (the lack of need to do anything on the PPC for the dial-up) is a BIG advantage of the old, DUN-based approach. I use a GPRS+ connection from my notebook a LOT and found having to start internet sharing manually very tiring on the long run (this is why, finally, I've switched back to using an old, DUN-based Sony-Ericsson t68i for dial-up.)

2. PAN client is NOT supported on many platforms; therefore, I wouldn't call BT DUN a legacy technology. Microsoft BT stack on Windows Mobile (while the Broadcom BT stack, naturally, works great with the BT PAN-based connection sharing); several older (non-MS / Broadcom) BT stacks even on the desktop; the Nokia 770/800, Palm OS, older versions of Mac (fortunately, as has been also pointed out in my AKU3 article, never versions of Mac OS X already support PAN). Also, Linux can be harder to configure to use PAN than DUN (for example, on my Sharp Zaurus C760, I've never managed to make BT PAN connections work, unlike BT DUN ones).

That is, it'd be REALLY great if Microsoft DID *force* phone manufacturers to make DUN available again, if it is already available. Not an optional package but an obligatory one."

[ScottC]

So, when they say that they have "great news" and that it'll be back in WM6 they are really saying "we screwed up as usual". This is up there with removing wifi AS.

[Mark Larson]

This is what I wrote to Greg:

I'm afraid I'm going to have to side with everyone who is ranting about Microsoft's tendency to remove more features than it adds with every new Windows Mobile release. I was very disappointed to find out that my new smartphone doesn't have Bluetooth DUN, since I need that to connect with my PC and my Axim Pocket PC.

Why does Microsoft insist on removing features with every new release? Every new version of Activesync has more features removed than added, I can't sync Money 2007 with my Pocket PC, I can't do sync over wifi, and now I can't do dialup with my phone. Looks like WM6/AS 4.5 will bring yet another litany of "Nope you can't do that anymore."

I also find your comment very disingenuous:
You're correct that Mobile Operators and OEMs have more control over the OS that will be released than Microsoft does. It's a fact of life that Mobile Operators call the shots in the Mobile phone space. Phones require their networks to run and are sold in their stores. It's natural that they'll decide which devices to allow on their networks and which devices to sell in their stores. For all people complain about MOs, I'm pretty sure that anyone who had spent the billions required to set up a network would want to have some control over what happens on it.

The problem is that while mobile operators do unfortunately control a large part of the average user's mobile phone experience, it is not the case in every market - phones sold in Europe, Australia, Middle East etc are mostly sold non-restricted and with most features left enabled. You could have handled it differently and you know it - instead of making DUN an optional extra, you could have made Bluetooth PAN an optional extra. It doesn't make sense how you can make an established technology optional. At the very least, you could let users download a patch to enable Bluetooth DUN functionality. Just because a technology is probably going to die, you don't try and kill it off by not letting the users decide for themselves.

AT&amp;T can't control what I plug into my landline RJ-11 jack, why should they have such strict control what I plug my SIM card into? You won't find any sympathy for the carriers here, sorry.

[Jon Westfall]

Now if WM 6 were available for my DASH, I'd be happy... I really miss DUN on that device.

[x51vuser]

there is in general a new trend at Microsoft to remove various features in their products. Stipped product is less complex, more stable, saves support costs and now also this:
http://www.nytimes.com/2007/04/19/technology/19soft.html?_r=1&amp;oref=slogin