There's an overflow crowd here at the 4GWE session on femtocells, so I'll try some liveblogging to keep you in the flow of the discussion if you're not here in the room with us. Keep refreshing this post, we are adding as it goes along.

What is a femtocell? David Chambers from Amdocs, our session moderator, gives the overview: It is basically a "complete [cellular] base station, shrunk to size."

Chambers says North America is a ripe femto market, since it has poor cellular coverage, good wired broadband, and people with money to spend. Theoretically :-)
David Nowicki, VP of marketing and product management from femto manufacturer Airvana, now speaking. Talking about the femto forum -- industry group promoting femto standards.

Femto Forum -- 43 operators, covering 1.3 billion subscribers; 17 of the top 20 mobile operators playing together.

What does the consumer get out of installing a femto? David says there's an 80-page white paper on the forum web site, woof! We'll read that later. Talking now about a family adding a femto to their house... it costs the operator at least $400 up front to integrate the device in -- but over the life of the customer contract it is worth it because ARPU goes way up. Could double the ARPU.

The family uses more data -- adds big-bucket calling plans -- more services, like TV -- so femtos can be a way to bring more bundles into a subscriber contract. Plus it offloads some data from the service provider network -- more savings.

Who will want femtos? Two-thirds (according to analysis) of customers are wireline customers who want mobility as a complementary service. Makes sense since you need a wired connection (ed. note -- or something like Clearwire's WiMAX) to connect the femto.

Now speaking: Don Troshynski, technical director at Acme Packet, going to talk about back end stuff. Why would you use a SIP-based femtocell? Going beyond R99 phone, get ready for IMS deployments.

SIP also means a need for controls... watching for DOS attacks, latency is a worry... so you need to make sure this is a well-engineered box. Worms and viruses, oh my! (little bit of fun animation on the powerpoint). Overall message: You have to consider the overall security solution when you are deploying these as a service provider.

Now up: Barlow Keener, Keener Law Group, on legal/reg issues of femto deployment.

Says the FCC first mentioned "femtocell" in Feb of 2008. They are "taking notice" but no rulemaking or decisions ... yet! 

Macro towers are now surrounded by barb-wire fences... now we are going to put those kind of towers into the hands of consumers, who can hack them, play with them, take them on vacation... "take it to Vermont, because I can't get service there."

Comparing VoIP regulation... net neutrality regulation... "femtocell looks a whole lot like VoIP service." Where will femto links fall when FCC takes a look? (And they WILL look, regulation normally lags the deployments)

Also need to think about 911 calls... triangulation... since you don't know where the antenna is, "much more difficult" to determine where the caller is calling from. GPS chip? Won't get to satellite in a building. "This is going to be an issue."

Billing -- providers don't want to talk about this. Roaming issues created when you move a femto to someone else's licensed territory... minutes that go through femto would be considered roaming... this could get ugly! (ed. note: Will airport security check you for femtos?) Could Internet providers "block" calls coming in through a femto? (ed. note: sounds like the full employment act for those lawyers who don't have net neutrality to argue about anymore)

Now open for audience questions. Any out there in cyberspace? email me at kaps at sidecutreports.com and I will relay.

Moving about -- can you bring your femto with you? Panelists say no, you can move to an area where your provider has spectrum, but not in other places. Apparently people tried this in Asia -- took their femtos with them, made "local" calls on the road. Providers will sniff this out, block it. (ed. note: Let's get ready to rumble!)

Question now about billing... guess from panel is that there may be "overflow" pricing, where if you don't use femto bandwidth you can roll it over. Might carriers bundle fixed service and femto mobile? "Hard to predict" what the billing dynamics might be. Could it cannibalize mobile services? Answer -- service providers are pricing this different ways. Sprint, $10 a month, all the calls you want. In Japan femtos are free -- create value by "recruiting" other family members to services -- or via apps like parental control, etc., specific to the femto. Too early to generalize how femtos/services will be priced.

Acme Packet's Don -- may be worth it to the operator to sacrifice price for benefits.

Keener -- says "it will come back to the lawyers" because of class action suits like the ones against AT&T and Apple about iPhones not performing. RAN engineers say they can't handle all the new data, femtos a way to offload.

Moderator David Chambers throws this one out: Is Wi-Fi (combined with things like Skype) a worthy competitor to femtos? Is that the real 4G competition, and not WiMAX vs. LTE? Acme Packet's Don: not going to replace the convenience of cellular. Keener: Think we are heading toward true convergence -- use Truphone, Skype... voice revenues dropping, the ability to deliver data will count more. That means ARPU will drop.

Airvana Dave: It will be both... all phones support femto, some will support Wi-Fi. 20 percent of handsets now have Wi-Fi... look at iPhone? Allows you to use Wi-Fi for Internet, but no operator (AT&T) services over Wi-Fi. Use both, for two different services. Keener again: OK to use Skype over your data "minutes"? (ed. note: Guessing this may be part of the next net neutrality battleground, don't you?)

Good audience question: Is a femto a better in-building solution than Wi-Fi? Airvana's Dave: That's what it's all about. If you want to support voice and data, do both. Femto primarily so everyone can make calls... Wi-Fi, good way to do Internet access. You could set up a network with only femtos... both voice and data, think if doing it today, still early days and you would do both. 

Audience: Is there a femto/Wi-Fi combo? Airvana's Dave -- manufacturers have such products, they have not been offered yet. Three years from now, you'll see mainly an integrated product. Keener "takes his lawyer hat off" and talks about the home gateway -- aka Holy Grail for the Netgears of the world. Music, video downloads, etc., to be stored there... (ed. note we have heard this idea before... but Tivos are still a niche... )

OK, got to sign off to do moderator duties. Thanks for reading!