Amazon.com has quietly introduced a 50 megabyte usage cap on Kindle owners using 3G-equipped models to browse web pages over AT&T’s 3G wireless network. Customers exceeding the limit after July 1 reportedly began receiving this pop-up message on their device:

The Experimental Web Browser is currently only available for some customers outside of the United States and may be limited to 50MB of browsing over 3G per month. This limit does not apply when customers are browsing over Wi-Fi.

The new usage cap does not affect users browsing Amazon.com, Wikipedia, and the Kindle store.

Web browsing on an electronic ink display instinctively has a built-in cap: the limited patience of the user trying to browse websites that were never designed for the Kindle experience.

But some enterprising hackers managed to jailbreak the Kindle device and turn its free 3G connection into a wireless mobile hotspot.

That means Amazon was footing the bill for Kindle owners who have re-purposed the device to provide Internet connectivity to wireless phones, laptops, tablets, and other Wi-Fi enabled devices.

At AT&T’s prices, Amazon decided to pull the plug after 50MB, which is barely enough for a few dozen busy web pages accessed during the month.

Time Warner Cable is facing possible prosecution for vandalism over sidewalk graffiti the company used in Redondo Beach, Calif. to advertise its Wi-Fi network — a service the city claims the company has no authorization to provide.

Redondo Beach officials immediately began receiving complaints the morning of July 5 when Time Warner Cable’s blue chalk advertising messages began appearing all over the city’s sidewalks.

City councilman Steve Aspel told the cable operator’s director of government relations that constituents were upset about the large promotional messages.

Time Warner’s Wi-Fi equipment (City of Redondo Beach)

“It really pissed me off and everybody in the neighborhood too,” Aspel told Time Warner’s Steven Sawyer. “Please have your company never do that again.”

Aspel told Sawyer nobody knew the messages were written in chalk, which will likely dissipate in a few days or sooner in any significant rain storm. The thought the cable company might have used blue paint on public sidewalks enraged several local residents.

But city officials were even more concerned about the fact Time Warner Cable has a Wi-Fi service up and running in Redondo Beach, without any permission from city officials to either install or operate it.

Assistant City Manager Marissa Christiansen told the council Time Warner was not allowed to operate any Wi-Fi network inside the city without explicit permission from the council. The city had been negotiating with the cable operator to grant permission to install the necessary Wi-Fi hotspots in the city’s right of way, but the cable company went ahead and installed them anyway, according to city manager Bill Workman.

“When we actually saw the markings on the sidewalk and put two and two together that it had all gone on without all the things we had discussed in those meetings, we, too, were very upset,” Workman said. “Very clearly, this is outside of their state franchise.”

Cable operators also require a building permit to install new equipment on public property.

Sawyer told the city council Time Warner apologized for the sidewalk markings, and the company moved quickly to remove them.

“We’ve done these markings in other cities and have never had an issue,” Sawyer said.

City attorney Mike Webb said there is an active criminal investigation underway to determine if the sidewalk messages are criminal graffiti, and was not in a position to elaborate as to if or when the cable operator would be prosecuted for violating the city’s municipal code.

Discussions about the Wi-Fi service itself are reportedly ongoing.

Time Warner Cable is planning major expansion of its network of Wi-Fi hotspots across southern California and into other service areas nationwide in the coming years.

Sprint is notifying their mobile hotspot customers the company is now prepared to enforce their formerly soft-capped 5GB plan with a $50/GB overlimit fee, billed at $0.05/MB increments.

Sprint has long informally capped customers using their phone as a Wi-Fi hotspot or tethered device, but until now was not prepared to enforce the limit because it could not accurately track usage.

“Starting June 2012, and effective on your next bill, your phone or tablet’s Mobile Hotspot on-network data allowance will be limited to 5 GB,” reads the message sent to Sprint customers.

Customers will begin receiving text message alerts when they reach 75% of their usage allowance, with repeated alerts at both 90 and 100%. When the 5GB limit is reached, Sprint will give customers the option of continuing service at the penalty price of $50/GB billed in megabyte increments, or shut the service down until the next billing cycle.

Some customers have been confused by the change, in part because Sprint has made a series of sometimes-confusing adjustments to their data pricing. But the company insists it has always had a limit on its mobile hotspot service, even if not enforced.

Smartphone customers using broadband on their phone still receive unlimited access. But other devices with mobile broadband access are usage capped based on the usage tier selected.

Wi-Fi access is about to become a lot more ubiquitous if you happen to buy broadband from Comcast, Time Warner Cable, Cablevision, Bright House Networks, or Cox.  All five companies on Monday announced they will open up their free Wi-Fi hotspots to customers of any of these companies nationwide.

The collaborative agreement extends the authentication platforms cable operators use to verify customer accounts when granting access to services like TV Everywhere — the online video streaming services operated by pay television providers. By sharing basic account information, customers traveling outside of their home cable service area can “roam” on free Wi-Fi networks operated by the other providers.

For example, a Cablevision subscriber who lives on Long Island will be able to access Bright House Networks’ Wi-Fi in central Florida or Time Warner Cable’s growing wireless network in Los Angeles.

The cable industry calls it a back door entry into mobile data, and unlike its existing partnership with Clearwire for WiMAX 4G service, Wi-Fi hotspots are available at no additional charge.

“We believe that Wi-Fi is a superior approach to mobile data,” said Kristin Dolan, head of projects at Cablevision. “Cable providers are best positioned to build the highest-capacity national network offering customers fast and reliable Internet connections when away from their home or business broadband service.”

More than 50,000 Wi-Fi hotspots are to be included in the project, all unified under the name “CableWiFi.”

Eventually, the companies hope to unveil automatic log-ins on the network, regardless of where customers access it.

The industry is aggressively expanding Wi-Fi services to give subscribers another reason to stick with their local cable company. Some may require customers to maintain both a cable-TV subscription and broadband to qualify for the service, others will only require a current broadband account. The free add-on may also make subscribers think twice about canceling service if it means losing access.

Comcast, Cablevision, and Time Warner Cable already have a deal in place to share their networks in southwestern Connecticut, New York City, parts of New Jersey and Philadelphia.

Cable operators will target high-traffic areas for Wi-Fi expansion — especially public parks, beaches, malls, eateries, stadiums and convention centers.  Don’t expect cable Wi-Fi to be common in residential neighborhoods, and users will have to temper their expectations. Most provide access suitable for web browsing and e-mail, but often have trouble keeping up with streaming video and other high bandwidth services.

“Disruptive” is perhaps too timid a word to use for Skype co-founder Niklas Zennstrom, the man who brought Excedrin-strength headaches to the music industry with file-swapping software Kazaa and streamed video across the net for free with Joost.  Now he wants to blow up America’s business model for expensive wireless data by literally giving it away to wireless phone users.

FreedomPop has a “freemium” business model of its very own — give away 1GB of 4G data through Clearwire to iPhone owners willing to use FreedomPop’s WiMAX-fitted phone case with the hope users will throw more business their way for around $10/GB after the first gigabyte is gone.

Zennstrom

Clearwire has been in the mood to make deals with all-comers to leverage its WiMAX network that carriers like Sprint plan to abandon for LTE 4G service in the not-too-distant future.  By giving away 1GB of free usage (and it remains unclear whether this is a “one-off” deal or if the meter resets to zero every month), the company is set to draw plenty of free press.

FreedomPop is likely to appeal to price-sensitive customers who don’t want to pay providers $30 a month for 2-3GB of usage when a much smaller, cheaper data plan combined with the free service will do.

The WiMAX case, which will fit over Apple’s iPhone, also acts as a mobile hotspot, supporting up to eight concurrently-connected devices.  No change of phone is required as users can connect to the service through Wi-Fi.

Customers will have to place a deposit on the case, likely less than $100, refundable when returned in good condition.

With most people not exceeding 1GB of usage per month, the only cost will be the “bare minimum” data plan customers are required to take with AT&T, Verizon Wireless, or Sprint, which currently runs $15-20 for a few hundred megabytes.

Clearwire’s WiMAX doesn’t deliver coverage to all points in the United States, and its speeds are considerably lower than 4G LTE service.  But free is free – a concept NetZero hopes to use to pitch a similar free 4G Clearwire WiMAX service.  The primary difference is your granted usage allowance.  FreedomPop will provide 1GB — NetZero 200MB.

[flv width=”512″ height=”308″]http://www.phillipdampier.com/video/WSJ How Skype Co-Founder Hopes to Make Money Giving Away Mobile Broadband on FreedomPop 3-23-12.flv[/flv]

The Wall Street Journal explores the business model of FreedomPop.  How can giving away 4G data succeed financially?  (4 minutes)