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Wideband codecs and IPR

Wideband codecs are a good thing. They have been slow to enter the mainstream, but there are several reasons why this is about to change.

Voice codecs are benefiting from the usual good effects of Moore’s law. Each year higher-complexity (higher computation load) codecs become feasible on low-cost hardware, and each year it is cheaper to fit multiple codecs into a ROM (adding multiple codecs increases the chance that two endpoints will have one in common).

Voice codecs are often burdened by claims of intellectual property rights (IPR) by multiple players. This can make it difficult for software and equipment vendors to use codecs in their products without fear of litigation. The industry response has been to create “patent pools” where the patent owners agree to let a single party negotiate a blanket license on their behalf:

Prior to establishment of the Pool, the complexity of negotiating IPRs with each intellectual property owner discouraged potential integrators.

Unfortunately there is still no pool for the standard wideband codec ratified by the 3GPP for use in cell phones, AMR-WB (G.722.2). Even where there is a pool, getting a license from it doesn’t mean that a use of the codec doesn’t infringe some yet-to-be-revealed patent not in the pool, and it doesn’t indemnify the licensee from such a claim.

There are several royalty-free wideband codecs available. I mentioned a couple of them (from Microsoft and from Skype) in an Internet Telephony Column.

Microsoft and Skype have got around the royalty issue to some extent by creating proprietary codecs. They have researched their algorithms and have either concluded that they don’t infringe or have bought licenses for the patents they use.

G.722 (note that G.722, G.722.1 and G.722.2 are independent of each other, both technically and from the point of view of IPR) is so old that its patent restrictions have expired, making it an attractive choice of common baseline wideband codec for all devices. Unfortunately its antiquity also means that it is relatively inefficient in its use of bandwidth.

Polycom did a major good thing for the industry when it made G.722.1 (Siren7) available on a royalty-free basis. G.721.1 is considerably better than G.722, though it is not as efficient as G.722.2.

The open-source Speex codec is efficient and royalty free, but being open source it bears a little more fear of infringement than the other codecs mentioned here. There are three reasons why this fear may be misplaced. First, the coders claim to have based it on old (1980’s) technology. Second, it has now been available for some years, and has been shipped by large companies and no claims of infringement have surfaced. Third, while it is possible in these times of outrageous patent trolling that somebody will pop up with some claim against Speex, a similar risk exists for all the other codecs, including the ones with patent pools.

So we now have three royalty-free wideband codecs (G.722, G.722.1 and Speex); we have hardware capable of running them cheaply; we have broad deployment of VoIP and growing implementation of VoIP trunking. We have increasing data bandwidth to homes and businesses, to the point where the bandwidth demands of voice are trivial compared to other uses like streaming video and music downloads. Plus there’s a wild card. By 2010 over 300 million people will have mobile smartphones capable of running software that will give them wideband phone conversations over a Wi-Fi connection.

Perhaps the time for wideband telephony is at hand.

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Counterpath’s new strategy

Counterpath has an enviable incumbency in the PC soft-phone market. Their eyeBeam soft phone is licensed by numerous service providers and PBX manufacturers. But the soft phone business is not enormous, so Counterpath is looking to use its leadership in the soft phone business as a beachhead into the fixed-mobile convergence space. Fixed-mobile convergence comes in two flavors: service provider and enterprise. So last year Counterpath made three acquisitions to fill in the spaces of a two by two matrix, with enterprise and service provider on one axis, and client software and mobility controller server software on the other.

Counterpath bought FirstHand for its Enterprise Mobility Gateway (EMG) and Bridgeport Networks for its service provider Network Convergence Gateway (NCG). It already had client software for service providers covered with its eyeBeam software. It bought NewHeights for its enterprise client software, a softphone with PBX features to complement the more consumer-oriented eyeBeam phone. These two soft phones have already been integrated by Counterpath into their new Bria softphone. It remains a challenge to get the soft phones and the two gateways working together seamlessly. It will also be a challenge to gain market share in the mobility gateway market.

Most mobility gateway vendors tend to focus on either service provider or enterprise customers, but Counterpath is not unique in having gateway devices for both. Tango Networks claims this as the differentiating feature of their solution; Tango’s two devices were designed from the outset to work together and complement each other. Counterpath must integrate two products with independent pedigrees. The NCG that came from Bridgeport is a pre-IMS solution. When a call comes in for a cell phone, the NCG can decide whether to ring the cell phone, a soft phone on a PC or both. The EMG that came from FirstHand is an enterprise mobility controller similar to RIM’s Ascendent product.

Neither of the two Gateways provides “true” FMC, namely the ability to run a call over Wi-Fi to a dual mode cell phone; this is presumably in the near future. The NCG fields calls to a cell phone number and directs them to a PC in the enterprise, while the EMG fields calls to the PBX and can route them to a 3G cellphone via a VoIP connection. What’s interesting about this particular solution is that it uses the 3G data connection for the VoIP call, rather than using the regular cellular voice connection. According to Counterpath the QoS (latency, jitter, packet loss) on the 3G data connection provides equivalent call quality to a cellular voice connection.

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Self-configuring Femtocells

Rethink Wireless reports that picoChip has added cognitive capabilities to their femtocells. Related “sniffing” technology is used in White Spaces radios and in the UNII-2 band by Wi-Fi. The idea is to check to see how the spectrum is currently being used, and to arrange matters to interfere as little as possible. With White Spaces and Wi-Fi the sniffing is used to avoid spectrum occupied by a primary user. PicoChip uses it to create self configuring networks:

As well has handling configuration, synchronization and hand-off – and reporting metrics on the cell to help network planning – the sniff function will support entirely self-organizing networks of the type Vodafone has outlined in recent presentations. Currently, most of the interference management these require are handled in different ways by the femtocell OEMs, but each has its own proprietary algorithms, making mixed-vendor networks difficult. The picoChip designs also allow the femto silicon to run the manufacturer specific code.

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Low cost international calls from your mobile phone

I wrote about the vast array of ways to bypass international tolls in my Internet Telephony column a while back. Now there is an interesting web site, LowCostMob.com, that gives a listing of the services available and technical explanations of how they work.

If you go to the “contact us” link on the website you can type in “user feedback” with mini-reviews of the services. I presume that over time the database of user comments will become an additional helpful resource on the site.

All these services work to make calls to international destinations cheaper, but if you actually travel abroad you still have to pay exorbitant roaming charges for using the cellular network. The benefit of dual-mode (Wi-Fi plus cellular) phones is that with some of them you can use the Wi-Fi connection to make VoIP calls and completely bypass the cellular network, avoiding international roaming charges. Not all the listed services support this feature, and not all dual mode phones do either.

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FCC Approves White Spaces!

This is incredible news. The FCC has done a wonderful thing, standing up to the broadcast TV lobby to benefit the people of America. What’s even better, four of the five commissioners are enthusiastically behind the decision:

It has the potential to improve wireless broadband connectivity and inspire an ever-widening array of new Internet based products and services for consumers. Consumers across the country will have access to devices and services that they may have only dreamed about before.

Some have called this new technology “Wi-Fi on steroids” and I hope they are right. Certainly, this new technology, taking advantage of the enhanced propagation characteristics of TV spectrum, should be of enormous benefit in solving the broadband deficit in many rural areas.

Today the Commission takes a critically important step towards managing the public’s spectrum to promote efficiency, and to encourage the development and availability of innovative devices and services.

While new broadband technologies are the most likely uses of these channels, the most exciting part about our action today is that we are creating the opportunity for an explosion of entrepreneurial brilliance. Our de-regulatory order will allow the market place to produce new devices and new applications that we can’t even imagine today.

The fifth commissioner, Deborah Taylor Tate, is only partly on board – she thinks some of this spectrum should be licensed, and she is concerned that not enough provision has been made for remediation in the event that interfering radios are deployed.

The FCC decision is a bold one – a more conservative positive decision would have been to approve a rural broadband access-only (802.22-style) use for now, but the commissioners went ahead and approved personal/portable use as well, which is what Google, Microsoft and numerous other computer and Internet industry companies have advocated.

The ruling imposed a geolocation requirement which will vastly increase the market for GPS silicon, though the trend in embedded GPS is to include GPS on the same die as other radios (like Bluetooth or cellular baseband) so whoever makes the White Spaces radio chips will probably be putting GPS on the same die by the second product generation.

The digital TV transition will open up the White Spaces spectrum in February 2009, but I will be very surprised if any white spaces consumer products appear in the market before 2010.

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DiVitas Test Drive

Divitas loaned me a Nokia E71 to try out with their mobile unified communications solution hosted by Sawtel. It’s a very nice phone – looks good, feels good in the hand. It’s also the best-sounding cell phone experience I have ever had, and that’s thanks to DiVitas. All cellular service providers use technology that sacrifices sound quality for increased carrying capacity. By squeezing down the bandwidth used by a call they can fit more calls into each cell, and get by with fewer cell towers, saving money. The standard codec around most of the world is GSM, and it’s the reason that cell calls can never sound as good as landline calls.

But DiVitas uses a Wi-Fi connection for your calls, and they have chosen to use the standard land-line codec, G.711. The effect is startling – a little disorienting even; we are so used to the horrible GSM codec that when a cell phone sounds as good as a land-line the subjective illusion is that it sounds much better.

This is one of the reasons that the type of voice over Wi-Fi solution offered by DiVitas is way better than the one offered by the telco industry, called UMA. UMA uses the GSM codec even over Wi-Fi connections.

But DiVitas didn’t stop with the sound quality. DiVitas has done an excellent job in several other technical areas. The fundamental technology of fixed mobile convergence is the ability to hand off a call in progress from the cellular network to the Wi-Fi network and vice versa.

This is very challenging, and it is an area where DiVitas claims to lead. So the first thing I did after turning on the phone was to make a call to check it out. I didn’t need to look at the on-screen indicator to know that the call was running over my office Wi-Fi network. The sound quality (did I mention this before?) was superb. So I walked out of range of the WLAN and sure enough the call handed over to the cellular network without dropping. There was a brief interlude of music and the call continued. Going back into the WLAN coverage area the handoff was completely seamless, perceptible only by the improvement in call quality as it moved from the cellular to the WLAN network.

Superior sound quality and seamless handover, while impressive to an engineer who knows what’s entailed, are not really sexy to regular users – it’s just a phone behaving like you would expect. DiVitas takes it to the next level by overcoming another technical challenge, delivering a polished, well thought-through, feature rich and well integrated user interface on the phone.

Actually, the DiVitas software client for the handset overcomes two challenges. The technical challenge of integration with the phone’s native software environment, and the design challenges of usability and usefulness. User interfaces are a matter of personal taste; the best are those that don’t get in the way of doing what you want. I disappointed the people at DiVitas by discarding their carefully written instructions and forging ahead by trial and error. Considering the potential consequences of this behavior I got away lightly. Everything worked the way I expected it to, and there were some nice touches, including Skype-like presence icons by the names in the directory.
While we’re on the topic of the directory, one thing that jumps out is the four digit phone numbers.

This is an indicator of yet another set of technical challenges that DiVitas has overcome to deliver their solution, namely integration with the corporate PBX, and presentation of the PBX features through the cell-phone user interface. DiVitas users will actually get a superior experience of the PBX through their cell phone compared to their desk phone. This is because the DiVitas software has a computer industry heritage rather than a telco heritage; it takes advantage of the nice big color screen with features like the presence icons and voice mail presented in an on-screen list like on the iPhone.

So the big news here is that a product has finally caught up with the hype around enterprise Mobile Unified Communications. All my criticisms (DiVitas got an earful) are nitpicking. For me the system worked as advertised, and that’s saying a lot.

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White Spaces Heat Up

In my last post I alluded to the techniques by which the TV broadcast industry was resisting the FCC’s exploration of unlicensed use of unused spectrum in the TV bands. These techniques appear to have borne fruit. Representative John Dingell has written to the FCC with some questions that they need to answer before their November 4th meeting that has White Spaces on the agenda.

I hope that Rep. Dingell keeps an open mind on this issue, and studies it sufficiently deeply to form a balanced opinion. I hope the FCC commissioners stick to their guns and argue persuasively for their plans.

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White Spaces Videos

I found this “grass roots” video on Google’s Public Policy Blog. That blog also has some interesting posts on related issues by Richard Whitt and Vint Cerf.

Looking at this provoked me to go to YouTube and search for other White Spaces related videos. I was interested to find a coordinated (by Google) effort by the proponents of White Spaces, and on the other side basically nothing – just this incredibly lame video that takes 7 minutes to tell us that microphones are used in sports broadcasting (don’t waste your time watching more than a few seconds – it’s the same all the way through).

It’s odd that the main opponents of Whitespaces (NAB and MSTV) haven’t put rebuttal videos on YouTube yet, and even odder that they haven’t found a need to present any more thoughtful analyses of the issue, equivalent (but presumably opposite) to those of Chris Sacca or Tim Wu. Instead, I have the impression that their strategy rests on the two prongs of public fear-mongering and bare-knuckled political lobbying.

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Green light for White Spaces

The eagerly awaited White Spaces test report of the Office of Engineering and Technology of the FCC came out on Wednesday. The operational paragraph in the Executive Summary reads:

We are satisfied that spectrum sensing in combination with geo-location and database access techniques can be used to authorize equipment today under appropriate technical standards and that issues regarding future development and approval of any additional devices, including devices relying on sensing alone, can be addressed.

It is huge that the FCC leaves the door open to devices relying on sensing alone, because even Google had begun to back off from this idea.

As expected, the report is a little more enthusiastic about fixed wireless Internet access, the kind of use advocated by the IEEE 802.22 working group, than it is about the personal and portable use advocated by Microsoft and Google, among others:

It will… allow the development of new and innovative types of unlicensed devices that provide broadband data and other services for businesses and consumers without disrupting the incumbent television and other authorized services that operate in the TV bands. The Commission is considering whether to also allow “personal/portable” WSDs to operate in the TV spectrum.

I have been following the White Spaces saga for some time (click on the “White Spaces” tag below, and the links to the right of this column); it is a great idea in theory, and if it turns out to work as hoped, the concept could eventually be extended across much more spectrum, leading to a nirvana of effectively unlimited cheap wireless bandwidth.

The commissioners plan to discuss White Spaces at their November 4th meeting.

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Verizon’s basic VoIP patents ruled invalid

Back in 2007, Verizon sued Vonage over three basic VoIP patents, and Vonage ended up settling for $120 million. It was a complicated story. Three US patents were involved: 6,104,711, 6,282,574 and 6,359,880. Verizon won that case, and was awarded $58 million plus a 5.5% royalty on Vonage’s future business. Vonage appealed, and the appeals court vacated the $58 million damages award and the 5.5% royalty. But it was on a minor point:

We hold that the district court did not err in its construction of disputed claim terms of the ’574 and ’711 patents. Therefore, we affirm the judgment of infringement with respect to those claims. However, we hold that the district court improperly construed one of the disputed terms in the ’880 patent, and accordingly vacate the judgment of infringement with respect to the ’880 patent and remand for a new trial… We vacate in its entirety the award of $58,000,000 in damages and the 5.5% royalty and remand to the district court for further proceedings.

But the case never went back to the district court! Verizon and Vonage had settled before the verdict, and under the terms of the settlement the verdict triggered a $120 million payment from Vonage to Verizon. Vonage went on to settle similar patent issues with AT&T for $39 million and Sprint for $80 million.

This year Verizon sued Cox on similar issues in the same court, Judge Claude Hilton’s court in the Eastern Virginia Federal District. This time Verizon lost. The jury found the claims of the ‘711 and ‘574 patents to be invalid, and Cox not guilty of infringing the others. Here is my summary of the claims that were found to be invalid:

US patent 6,104,711:
Claim 1 – A DNS (or similar) server translating an address based on a condition
Claim 3 – Like claim 1, where the condition is the status of an endpoint
Claim 11 – Like claim 1, where the condition is a query of an endpoint

US patent 6,282,574:
Claim 5 – Like 711.1, where the server returns a phone number (but no condition is involved)
Claim 6 – Like 574.5, where the server returns a phone number plus an IP (or similar) address

Presumably Verizon will appeal, but to this layman they seem unlikely to win. Their previous victory over Vonage was pyrrhic; the definitions returned by the Markman hearing in that case and the reasoning of the appeal court ruling broadened the scope of the patents to the extent that they encompassed a ton of prior art, as you probably expected when you saw the claim summaries above.

There are numerous patents covering VoIP, and numerous patent holders wanting a slice of the pie. James Surowiecki wrote a characteristically good piece on this type of situation in the New Yorker in August.