Enterprise Mobile Security


Archive for the ‘Bluetooth’ Category

Wi-Fi for Mice and Keyboards

Wednesday, June 23rd, 2010

A while back the Wi-Fi Alliance announced a new certification program, Wi-Fi Direct, which enables a PC to connect directly with other Wi-Fi devices without having to go through an Access Point.

The Wi-Fi certification process for Wi-Fi Direct is scheduled to be launched by the end of 2010, but there are already two pre-standard implementations of this concept, My Wi-Fi, an Intel product which ships in Centrino 2 systems, and Wireless Hosted Network which ships in all versions of Windows 7.

The Wi-Fi Direct driver makes a single Wi-Fi adapter on the PC look like two to the operating system: one ordinary one that associates with a regular Access Point, and a second acting as a “Virtual Access Point.” The virtual access point (Microsoft calls it a “SoftAP”) actually runs inside the Wi-Fi driver on the PC (labeled WPAN I/F in the Intel diagram below).

To the outside world the Wi-Fi adapter also looks like two devices, each with its own MAC address: one the PC just like without Wi-Fi Direct, and the other an access point. Devices that associate with that access point join the PC’s PAN (Personal Area Network).

This yields several benefits in various use cases.

I wrote a couple of years ago about how a company called Ozmo planned to use a Wi-Fi PAN to connect peripherals to PCs, replacing Bluetooth and proprietary wireless technologies. That plan has now come to fruition. Earlier this month Ozmo announced that it had received $10.8 million in additional funding, and this week it announced two major customers: Primax, a leading ODM of wireless mice, and NMB Technologies, a leading ODM of wireless keyboards.

Here’s a slide from one of their promotional presentations giving a comparison with Bluetooth and proprietary technologies:
Comparison of Ozmo's low power Wi-Fi technology with Bluetooth and proprietary solutions for Human Interface Devices (HIDs)

The essence of Ozmo’s approach is low cost, multi-device, low bandwidth and low power consumption. Wi-Fi Direct has another use case that is high bandwidth, with no requirement for low power.

If you want to stream video from your PC to a monitor using traditional Wi-Fi (“infrastructure mode”) each packet goes from the PC to the access point, then from the access point to the TV, so it occupies the spectrum twice for each packet. Wi-Fi Direct effectively doubles the available throughput, since each packet flies through the ether only once, directly from the PC to the TV. But it actually does better than that. Supposing the PC and the TV are in the same room, but the access point is in a different room, the PC can transmit at much lower power. Another similar Wi-Fi Direct session can then happen in another room in the house. Without Wi-Fi direct the two sessions would have to share the access point, taking turns to use the spectrum. So we get increased aggregate throughput both from halving the number of packet transmissions, and from allowing simultaneous use of the spectrum by multiple sessions (if they are far enough apart).

A Wi-Fi buff would point out that you can already do all this with ad-hoc mode, but Wi-Fi Direct purports to be usable by mortals, and to work interoperably, neither of which could be said for ad-hoc mode until recently. In January Infinitec announced a new point-to-point video streaming product that claims to be easy to use and universally interoperable, that Engadget implies uses ad-hoc mode, though Google can’t find the words “ad hoc” on the Infinitec website.

Between the bandwidth extremes of mice and TVs, lie numerous other potential uses, like headsets (which Ozmo also supports); syncing phones, cameras and media players; and wireless printers.

Wi-Fi Ubiquity

Thursday, June 3rd, 2010

ABI came out with a press release last week saying that 770 million Wi-Fi chips will ship in 2010. This is an amazing number. Where are they all going? Fortunately ABI included a bar-chart with this information in the press release. Here it is (click on it for a full-size view):

Wi-Fi chip shipments worldwide. Source: ABI

The y axis isn’t labeled, but the divisions appear to be roughly 200 million units.

This year shows roughly equal shipments going to phones, mobile PCs, and everything else. There is no category of Access Points, so presumably less of those are sold than “pure VoWi-Fi handsets.” I find this surprising, since I expect the category of pure VoWi-Fi handsets to remain moribund. Gigaset, which makes an excellent cordless handset for VoIP, stopped using Wi-Fi and went over to DECT because of its superior characteristics for this application.

There is also no listing for tablet PCs, a category set to boom; they must be subsumed under MIDs (Mobile Internet Devices).

The chart shows the portable music player category growing vigorously through 2015. iPod unit sales were down 8% year on year in 1Q10, and pretty much stagnant since 2007. ABI must be thinking that even with unit sales dropping, the attach rate of Wi-Fi will soar.

The category of “Computer Peripherals” will probably grow faster than ABI seems to anticipate. Wireless keyboards and mice use either Bluetooth or proprietary radios currently, but the new Wi-Fi alliance specification “Wi-Fi Direct” will change that. Ozmo is aiming to use Wi-Fi to improve battery life in mice and keyboards two to three-fold. Since all laptops, most all-in-one PCs and many regular desktops already have Wi-Fi built-in (that’s at least double the Bluetooth attach rate) this may be an attractive proposition for the makers (and purchasers) of wireless mice and keyboards. Booming sales of tablet PCs may further boost sales of wireless keyboards and mice.

Dual-mode technology maturing

Thursday, August 27th, 2009

The Rethink Wireless newsletter is always worth reading. An article in today’s edition says that according to ABI dual mode handset shipments are on track to double from 2008 to 2010, and more than double from 2009-2011 (144 million units to 300 million units).

Rethink’s Matt Lewis cites improved performance and usability as driving forces, plus a change in the attitudes of carriers towards hot-spots. Wireless network operators now often have captive Wi-Fi networks and can use them to offload their cellular networks.

The upshot is a prediction of 300 million dual mode handsets to ship in 2011: 100% of the smartphone market plus high end feature phones.

The attach rate of Wi-Fi will continue to grow. By 2011 the effects of Bluetooth 3.0 will be kicking in, pushing Wi-Fi attachment towards 100% in camera phones and music phones in ensuing years.

Bluetooth 3.0 arrives

Thursday, April 23rd, 2009

The Bluetooth 3.0 specification has finally been ratified.

The main new feature is the Alternate MAC/PHY (AMP), that lets Bluetooth piggyback on Wi-Fi for high speed data transfers. The way it works is that applications write to the traditional Bluetooth Profile APIs, and connections are negotiated using the traditional Bluetooth radio. But then for high-speed data transfers the system switches to a direct peer-to-peer Wi-Fi session. This enables things like bulk syncing of photos from your phone to your PC, or streaming uncompressed CD stereo audio to wireless loudspeakers.

I wrote about Bluetooth AMP before, wondering why it retained a dependency on Bluetooth radio. The answer is that in idle, listening mode waiting for activity, Bluetooth is more power efficient than Wi-Fi, while Wi-Fi is more power efficient for bulk data transfers. This makes Bluetooth’s other next big thing, LE (formerly Wibree), an interesting complement to AMP: for power efficiency Bluetooth devices will reside in two modes, very low power idle mode (LE), and Wi-Fi mode when transferring data.

The Bluetooth 3.0 specification talks about 802.11 rather than 11g or 11n, since 802.11n is not yet ratified, but some of the companies involved will be supporting draft 802.11n anyway.

From an industry point of view there are several interesting aspects to this announcement, among them:

  • Atheros’ ascendence. Atheros, a leader in Wi-Fi, only recently got into the Bluetooth market, and currently only plays in the PC Bluetooth market. It dabbled in headset Bluetooth and got out, and has not yet announced Bluetooth for handsets. So Atheros is a minor player in Bluetooth, eclipsed by CSR and Broadcom, and several others. But Kevin Hayes of Atheros was the technical editor for the 802.11 Protocol Adaptation Layer of the Bluetooth 3.0 specification, and Atheros supplied the video and the demo of AMP at the 3.0 announcement event.
  • Potential movement of Wi-Fi into feature phones. Handset makers slice the market into four main segments: ultra low cost phones, basic phones, feature phones and smart phones. Wi-Fi is now pretty much ubiquitous in new smartphones, but effectively absent in all other types of cell phone. But feature phones have music and cameras which generate exactly the data that Bluetooth 3.0 was designed to sync with PCs, so Bluetooth 3.0 provides a motivation to handset manufacturers to add Wi-Fi to their feature phones. This will vastly boost the Wi-Fi attach rate in 2010 and beyond.
  • Another nail in the coffin of UWB (Ultra Wide-Band). In its original conception, AMP was to use WiMedia’s flavor of UWB. Later Wi-Fi was added to the mix, and now UWB is absent from the spec. UWB has so far failed to meet its performance expectations, and rather than fix it the WiMedia Alliance threw in the towel in March 2009. I suppose it is possible that the few companies still toiling away on fixing UWB will eventually overcome its performance woes, and that it will get adopted into the Bluetooth specification.

Broadcom connectivity chip reaches the market

Friday, September 12th, 2008

Back in July Broadcom announced that it had started production shipments of its BCM4325 chip.

Yesterday iFixit.com found one in the new Apple iPod Touch. This is the first published instance of a device containing this chip but many more will follow. Broadcom has scored a coup with this device; it contains Wi-Fi, Bluetooth and FM, all on a single die fabricated on a 65nm process.

This is the most highly integrated connectivity chip (the term refers to all the non-cellular radios in a phone) yet to reach the market. Previous combo connectivity chips have combined Bluetooth with FM, and in one instance (from Marvell) Bluetooth with Wi-Fi. But the BCM4325 is the first to market with three radios. TI has announced, but not yet shipped, a similar chip with even more impressive specifications: the TI Wi-Fi will include 802.11n and the TI FM will include transmit as well as receive.

Connectivity technology in cell phones is evolving very rapidly, as the phone manufacturers accelerate their competition on the feature treadmill. Next will be GPS, driven this time by the network operators, who see location-based services as a potential goldmine. Two chip manufacturers have announced, but not yet shipped, combo Bluetooth, FM and GPS chips.

Connectivity chips were the subject of a report I wrote last year with the Linley Group; we will deliver an update with expanded coverage later this year.

CSR 2Q08 results: in line. Company focusing on “Connectivity Centre”

Tuesday, July 29th, 2008

CSR released its 2Q08 results today. Quarterly revenues are 13% down year on year ($188.4m vs. $215.9m), but in line with expectations and up 17% on Q1. The CEO blamed the decline on “macro economic pressures.”

The press release says that CSR has completed “repositioning the business around the Connectivity Centre.”

What CSR calls the “Connectivity Centre” was the topic of a report I wrote with the Linley Group last year and which we are in the process of updating for 2008. The idea of the connectivity chip is that cell phones have a multiplicity of radios in them these days: several cellular standards and frequencies, Bluetooth, FM radio, GPS, Wi-Fi and some other minor ones. The way it has shaken out so far is that cell phone OEMs have implemented each of the non-cellular radios separately on their phone motherboards, or with two or more of them mounted together on a multi-chip module, or “connectivity chip.” Recently many vendors have started doing single-die implementations of connectivity chips, like Bluetooth plus FM, or Bluetooth plus Wi-Fi.

CSR with its BlueCore 7 is the first to combine Bluetooth (plus Bluetooth LE, formerly Wibree), FM (transmit and receive) and GPS on a single chip. This looks like a winning combination, because these three technologies are the ones with the highest attach rates to cell phones, and CSR has managed to implement the GPS with a sufficiently modest silicon footprint that CSR doesn’t charge for it if the OEM doesn’t want to use it.

Also mentioned in CSR’s results release is the news that the low-power Wi-Fi chip that CSR announced in 2004, the UniFi 2, is finally shipping in phones: “our embedded Wi-Fi product will be shipping in six smart phones by the end of the current quarter.” Actually, one of their analyst presentations appears to indicate that it is already shipping in the Mio A702.

CSR says it is “the only ‘pure play’ connectivity company.” This is passably true, but each of the major cellular baseband companies except Freescale now has, or is in the process of putting together a suite of connectivity products. CSR also says it “is moving fast to create and lead this market.” It will have to move fast. Qualcomm has already swept multiple connectivity technologies into its latest cellular baseband offering. This is the likely end-game for all the cellular baseband vendors. The questions are: is this what the handset OEMs want, and if so, how long will it take?

More on Ozmo

Wednesday, July 16th, 2008

A while back I wrote about Ozmo, a company that plans to replace Bluetooth with Wi-Fi in certain applications.

Ozmo’s pitch is that their special version of Wi-Fi is faster, less prone to interference, cheaper and more power efficient than Bluetooth. Though slow for Wi-Fi, Ozmo’s data rate of 9 Mbps is way better than the 3 Mbps of Bluetooth 2.1 plus EDR. Concerning interference, Bluetooth transmissions are in the same 2.4 GHz frequency range as Wi-Fi, so careful engineering is always needed for coexistence; but coexistence is not an issue for Ozmo, because it is a flavor of Wi-Fi. The lower-cost part of the story is that while an Ozmo chip for a peripheral is roughly the same price as a Bluetooth chip, it saves the need for a Bluetooth chip in the host device. So if Ozmo’s claims of double the battery life of Bluetooth turn out to be valid when tested, the pitch holds water.

Bluetooth is unshakably incumbent in the billion-unit-per-year mobile phone market; most phones are now shipping with Bluetooth. But in laptops the Bluetooth attach rate is still well under 50%, while the Wi-Fi attach rate is close to 100%. So it makes sense that Ozmo is focusing initially on the computer market. Ozmo enables a laptop to use wireless peripherals like mice, keyboards, game controllers and headsets with a software modification to the Wi-Fi rather than having to include a USB wireless receiver in the package.

Ozmo is also focusing on the Consumer Electronics market, where Wi-Fi is gaining traction, and where the ability to support wireless remotes and similar peripherals can be added ‘free of charge’ to a device that already has Wi-Fi.

Since this is a compelling proposition, OEMs in these markets are likely to fall into line relatively easily, and indeed Ozmo has already secured the support of the biggest fish in the PC pond, Intel.

It may be a harder sell to the peripheral manufacturers. For them it’s not just a software upgrade. It is a new product line, one that depends on a single source for a key component and that sells into a currently non-existent base of host devices.

On the other hand, the peripheral device manufacturers may not be oposed to a new product line – they already have a plethora of products, using a variety of connectivity technologies including proprietary ones. Adding another one may not be too arduous, especially if it removes the need for a USB part. Ozmo could overcome the non-existent base issue by supplying, or convincing Intel and the other PC Wi-Fi chip vendors to supply, upgraded drivers for legacy Wi-Fi devices.

Wi-Fi Bluetooth collision

Thursday, June 12th, 2008

I already wrote about how Bluetooth is specifying Wi-Fi for its high bandwidth transport in a future version. Now there’s another interesting Bluetooth/Wi-Fi juxtaposition.

You may remember that last year Bluetooth subsumed WiBree as an ultra low power consumption variant. Now something analogous is happening in Wi-Fi, where a startup called Ozmo has come up with an ultra low power variation of Wi-Fi, which it is pitching as a substitute for Bluetooth.

Ozmo is not the first to propose this. Nanoradio claims that its implementation of Wi-Fi consumes way less power than Bluetooth, and they have a reference design for a Wi-Fi headset to demo the concept. Atheros has also recently announced a low-power Wi-Fi chip – so low that they claim “near zero” stand-by power consumption.

So Ozmo may not be so radical in its low-power claims, but it also claims low-cost. The Ozmo chip is priced the same as Bluetooth chips, which Ozmo estimates are between 1/4 and 1/3 the cost of Wi-Fi chips.

The Atheros and Nanoradio chips are full implementations of Wi-Fi; Ozmo’s is, according to this EETimes article, a “stripped down” version. This may mean that it is a non-standard version, in which case it would need a new certification program from the Wi-Fi Alliance – not a major obstacle, I presume, in view of Intel’s strong support for Ozmo.

So why would anybody want a version of Wi-Fi to substitute for Bluetooth, when we already have Bluetooth? Well, while most phones come with Bluetooth these days, in the PC world Wi-Fi is far more common than Bluetooth. So for peripherals designed exclusively for PCs, like mice and keyboards, Wi-Fi makes more sense than Bluetooth simply on the grounds of out-of-the-box compatibility. Add the technical benefits, like coexistence (Bluetooth and Wi-Fi tend to step on each others’ toes) and superior performance (Ozmo claims double the battery life in similar applications to Bluetooth), and it seems like a no-brainer.

The factors that could cause it to fail are ease of use and price. The setup of the peripherals with the PC must be completely automatic, and the operation of the devices must be flawless. Peripheral manufacturers must produce Wi-Fi versions of all their wireless products, and price them the same as their Bluetooth versions. The Wi-Fi drivers on the PC side will have to be modified in order to permit the PC Wi-Fi to communicate simultaneously with access points and peripherals. This is being done anyway by Intel, in a project called “Cliffside.”

All these impediments are mitigated considerably by Intel’s involvement. Intel makes most of the Wi-Fi chips in PCs, and presumably these chips will support the Ozmo products. With this assurance, peripheral manufacturers will feel comfortable going ahead with Ozmo-powered products.

Bluetooth over Wi-Fi

Friday, February 22nd, 2008

The Bluetooth SIG put out a press release the other day saying that by mid-2009 a specification that includes Wi-Fi as an “alternate MAC/PHY” will be released.

This is the relevant part of the release:

What we’re doing is taking classic Bluetooth connections – using Bluetooth protocols, profiles, security and other architectural elements – and allowing it to jump on top of the already present 802.11 radio, when necessary, to send bulky entertainment data, faster. When the speed of 802.11 is overkill, the connection returns to normal operation on a Bluetooth radio for optimal power management and performance.

So this innovation specifies an interface above the Bluetooth MAC layer that enables Bluetooth session data to flow through a Wi-Fi radio instead of a Bluetooth one.

The press release says that the Alternate MAC/PHY will be used to do things like:

Wirelessly bulk synchronize music libraries between PC and MP3 player.
Bulk download photos to a printer or PC.
Send video files from camera or phone to computer or television.

But the new specification will only be useful in devices that already have both Wi-Fi and Bluetooth, and Wi-Fi can do these things without any assistance from Bluetooth. So the increment in value may be small; but Bluetooth can still bring something to the table. According to Wikipedia,

The Bluetooth Radio will still be used for device discovery, initial connection and profile configuration, however when lots of data needs to be sent, the high speed alternate MAC PHY’s will be used to transport the data.

It seems oddly limiting not to go the whole way, and enable Bluetooth applications to run on top of Wi-Fi even when there is no Bluetooth radio.

CSR pitches better sound quality, battery life in Bluetooth headsets

Wednesday, September 5th, 2007

CSR announced their Bluecore 6 chip today. It will ship in production volumes in January 2008. CSR claims a more robust connection – with increased transmit power and receive sensitivity. CSR also claims a breakthrough in sound quality, achieved by going from a Continuous Variable Slope Delta (CVSD) codec to Adaptive Differential Pulse Code Modulation (ADPCM). This enables packet retransmission and a halving of transmission bandwidth. The reduced bandwidth requirement results in a reduction in power consumption, and the ADPCM codec yields a MOS of 4.14 compared with a maximum of 2.41 for CVSD.

This is a welcome change, but doesn’t really go far enough. What’s needed is a wideband codec like AMR-WB to yield better-than-toll quality sound. While this would be redundant in a regular cell phone – ADPCM is more than adequate to carry a signal that has been encoded in GSM – it would make a huge difference in dual-mode phones carrying Voice over Wi-Fi.