Packet core

AlcaLu Tackles Wi-Fi Handoff

Alcatel-Lucent (NYSE: ALU) is outfitting its 7750 Service Router to be a Wi-Fi gateway, handling the handoff between cellular and wireless LAN networks.

The company is calling Tuesday's announcment lightRadio Wi-Fi, but for the moment, it has more to do with a Wi-Fi card on the 7750 than with the little cubes of last year's lightRadio announcement.

The idea is to have the network move a user from wireless LAN to 3G to 4G depending on what's available and which connection seems the least congested. The 7750 would become the gateway, the point where the network shunts traffic to one core or the other, and the handoff would include secure authentication onto the Wi-Fi network.

The decision about when to hand off is handled by a new control module added to the 5780 Dynamic Services Controller, AlcaLu's policy and charging rules function (PCRF) system. AlcaLu calls this feature the Automatic Network Discovery and Selection Function (ANDSF).

Finally, lightRadio femtocells and Metrocells are going to get Wi-Fi added as an option, but not until at least the fourth quarter of 2012. The enhancements to the 7750 and 5780 are due out in the second quarter.

Why this matters
Wi-Fi has become a bigger part of mobile operators' plans, thanks in part to initiatives such as the Wi-Fi Alliance's Hotspot 2.0. "Mobile operators are talking about Wi-Fi as trusted access and therefore on a par with 3G, where previously it's been considered a risk and not carrier-grade access," says Gabriel Brown, an analyst with Heavy Reading .

That trend might also explain Ericsson AB (Nasdaq: ERIC)'s rumored interest in BelAir Networks Inc.

Putting this function near the wireless packet core is a new idea. The alternative today is to have the handset deal with the handoff, which is a difficult model to scale and also cuts the operator out of the loop whenever Wi-Fi is invoked, Brown says. So, operators wouldn't prefer that.

Users would get some benefit, too. For one thing, smartphone-based handoffs secure the Wi-Fi authentication but not the data you send across the network afterwards, Brown says. A network-based handoff could take care of that.

For more
More about melding the Wi-Fi and cellular networks: — Craig Matsumoto, Managing Editor, Light Reading

reachanil 12/5/2012 | 5:42:41 PM
re: AlcaLu Tackles Wi-Fi Handoff

The ANDSF is a standard EPC element that instructs the mobile device to select either a Wi-Fi network or a 3G/4G network based on policies. However, this would do a full offload of all of the user's traffic to Wi-Fi or keep all of them on 3G/4G. It will be interesting to see if ALU's solution supports offloading the user fully to Wi-Fi radio access where that is available, but then at their edge gateway selectively route certain "Flows" to the 3G/4G core network, while offloading the rest of the traffic to the internet. So, that way the operators can "Offload" at the RAN, saving on spectrum, but then "Onload" certain traffic back to their core network for providing mobility, and other services for flows which need them.

rhr 12/5/2012 | 5:42:40 PM
re: AlcaLu Tackles Wi-Fi Handoff This is a nice announcement and I wonder why other vendors haven't done something similar. Don't know if there is a diagram you can add to show where this sits within the network. This ALU announcement is either Wi-Fi or cellular. SK Telecom announced recently its Het-Net sol that can use both simultaneously. Clearly that needs a special handset but how is that handled within the network?
Rupert_Baines 12/5/2012 | 5:42:34 PM
re: AlcaLu Tackles Wi-Fi Handoff

Interdigital & Picochip did a demo of "smart" WIfi + Femjto integration last year.


The two cases they discussed were:

<li>"traffic aware" policy mangement eg buying a video the purchase over HTTPS could go via 3G, nad be billed to your account (no need for a credit card; with fullk traceability and security), while the download of the video would stream over WiFi</li>
<li>link quality mangement (as you suggest), routing traffic over bother beaeres and monirot relatice performance to allow sharing or hand off between them.
For excample, in your home traffic is mostly over WiFi, as you walk out tof the door it shifts to femto &amp; 3G - which could then do a 3G handout to the umbrella macrocell.</li>

&nbsp;I think we will see more examples of people combining these technologies to deliver better sercices to customers.

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