stokelogo.bmpWe wrote about Stoke, the start-up working on a way to let you switch your mobile phone to your better, WiFi connection at home, when you arrive there.

And when you leave your home, it will switch your phone back to the cellular network, until you arrive at work, at which point its switches back again to hook up with your employers’ broadband — all the while letting you use the best network available.

See our original story here.

It doesn’t do that merely for mobile phones, but for any device — as long as your carrier incorporates Stoke’s technology.

The Mountain View company essentially makes fixed line, wireless, DSL and cable networks all one big network, “so that they all play together,” said Keith Higgins, vice president of marketing.

In 2004 and 2005, Kleiner Perkins Caufield & Byers, Sequoia Capital and others injected $30 million into Stoke. Now the company has raised $20 million more, led by new investor DAG Ventures and including existing VCs, Kleiner Perkins and Sequoia Capital. Northgate and the Ontario Teachers’ pension participated too.

Stoke’s product • the Stoke Session Exchange (SSX) • has won some customers, including a large carrier in Japan, VP of Marketing Keith Higgins told VentureBeat. Ten or so other operators are looking to strike deals on fixed-wireless convergence technologies, and so he hopes to make more announcements soon. Stoke’s role is very specific — it focuses on “session management,” meaning it does things like authenticate users when they call into the network, manage policies governing those users, and so on. It is up against the traditional subscriber manage vendors (Redback, Juniper, etc.), says Rick Thompson, Senior Analyst, at Heavy Reading. Thompson expects these players to soon role out similar services.

Higgins tells VentureBeat that the main challenge will be to get carriers to upgrade their technology, something analysts agree with. Joe McGarvey, analyst with Current Analysis, says:

Is the market ready for it? If you are asking if carriers are going to go out and dump all of their existing access infrastructures and adopt the Stoke box the answer is no. However, the Stoke device is build in a modular manner that makes it possible for carriers to adopt the technology to delivery one or two functions and then perhaps migrate other functions to the box down the road, as the carrier further consolidates its infrastructure.

We mentioned other companies operating in fixed-wireless convergence in our previous story. Some include Azaire Networks (which has raised about $32 million), BridgePort (about $51 million), Kineto Wireless (about $77 million) and LongBoard (about $65 million) and Reefpoint (about $120 million).

See diagram below, illustrating how Stoke wants to allow someone to switch between networks: