Inside DiVitas

Location-based Mobile Unified Communications: Babes lost in the woods

By Rich Watson

A major pitfall with Location-Aware-based Mobile Unified Communications (Mobile UC) is that it tends to confine your roaming to a campus that has been Location-Aware-mapped (In a mapped environment, the exits of the Location-Aware environment have been identified). Once you step off campus, and out of corporate WiFi range, the Location-Aware capabilities are no longer enforced, and you impact the key advantage that Location-Awareness has to offer: extending battery life.

WiFi is notorious for over-taxing dual-mode phone batteries, and Location-Aware, in theory, intends to help extend battery life. BTW, Environment-Aware technology has a similar design goal, and they both achieve this by minimizing the frequency of accessing the WiFi radio.

The catch: The Location-Aware approach is not without sacrifice.

For example, Location-Awareness may assist you when you are roaming from WiFi to cellular (i.e. leaving a building). However, it’s actually a hindrance when you are trying to roam in the other direction – from cellular to WiFi. This is because your smartphone isn’t getting the Location-Aware help it needs to connect with a WiFi network, so your phone must work extra hard by constantly seeking a WiFi signal. If this process is too frequent, it will quickly run down the battery. At the same time, if it’s too infrequent, “finding” a WiFi network will be delayed, and this threatens to increase use of cell minutes.

In addition to sometimes hurting, rather than helping, battery life, Location-Aware solutions are blind to hotspots (mapping the office is one thing, but mapping every Starbucks is probably not so practical).

What this means, for example, is that your Location-Aware phone knows when it’s left the corporate building, and thus it roams to cellular. But it isn’t immediately aware of the available WiFi when you walk into a hotspot like Starbucks. You could be sitting on a couch for a long while with your Chocolate Frappuccino before your phone ever realizes there’s WiFi to be had (the application must actually invoke a scan periodically for the WiFi driver to wake up and look around for an access point).

Even a roam back onto campus could be delayed … remember this type of solution is primed for leaving WiFi, not entering a WiFi zone!

In contrast, an Environment-Aware solution like DiVitas is always at the ready when it comes to roaming. DiVitas continually seeks the optimal connection – whether it’s cellular, your corporate WLAN, your home office WiFi or hotspots such as Starbucks and an airport. And it does this with the least impact on the battery-life possible.

An Environment-Aware solution is always monitoring the phone’s environment, and it isn’t limited to location. In doing so, DiVitas scans for WiFi once about every 60 seconds, which is sufficient to quickly locate a WiFi signal, but not so often that it will run down the battery.

What does this mean to us DiVitas users? We can communicate via smartphone when we are in the office, at home, or at a hotspot such as Starbucks, the airport or on a busy city street covered by metro WiFi. We know we are constantly connected to the optimal, available network, whatever that may be.

Being environment-agnostic makes the most sense…the device behaves the same in any environment.

Mobile Unified Communications, WiFi, FMC, GSM, CDMA … Can You Hear Me Now?

By Rich Watson

A really interesting question came up via email in response to a recent NetworkWorld article on DiVitas, and we thought it would make for some good blog material. (See Mobile UC: The ultimate end game)

Email: Who is doing the mobile unified communications with CDMA? I have met with [another vendor] and they tell me it is only available via GSM. 

• Our response to the statement in this email: So not true!
• The answer to the question in this email (and why the previous statement isn't true): DiVitas Mobile UC most definitely supports CDMA.
• Our question to this other vendor: Why would you limit your solution (and your sales) by ignoring millions of subscribers? Why not just create a huge pile of money and have yourself a big bonfire? We are baffled by this squandered opportunity.

On a more serious note, it’s true that CDMA is the orphan cellular network, given that most of the world today uses GSM. It is estimated that CDMA has only 270 million subscribers worldwide (including half of the U.S., which is the largest country using CDMA). Compared with GSM, which is estimated to be over 1 billion, this is just a drop in the bucket.

But regardless of which number is the highest, there are apparently still enough (millions) faithful users in the U.S. that CDMA-based Verizon and Sprint are making a healthy living. (Note: CDMA may be primarily U.S.-deployed, but it’s a really big country). And the average American doesn’t have a clue which network-type they are using anyway. They just want the best deal on a reliable service.

Yes, other enterprise-based solutions and carrier-based FMC solutions have totally ignored the lonely CDMA networks. But DiVitas hasn’t. Conversely, our vendor- and carrier-agnostic architecture embraces all kinds of wireless services, and even supports mixed (GSM and CDMA) network sites.

Some day in the near future a CDMA-FMC consumer will be able to say “can you hear me now” over any wireless network – WiFi or cellular!

Beware, Location-Aware (FMC) Part 2

By Rich Watson

In my last blog, I talked a little about the shortcomings of location-aware technology, especially as it compares with DiVitas’ more flexible environment-aware approach to seamless roaming. We’re going to continue with this topic because of some recent questions we’ve received about the differences between location-aware and environment-aware technologies. For example, we were recently asked if a location-aware solution is better for organizations that want a detailed map of their environment for management purposes.

The answer? Creating a detailed map of your WLAN is critical for reliable mobile communications (especially one based on seamless-roaming), but tying that map to the “roam” itself is not a good idea. And here are 3 reasons why:

DEAD ZONES

Location-Aware: No matter how hard you try, there will always be dead spots (i.e., no coverage) within a WLAN network. These “dead zones” result from under-coverage (by design) or geometry of the facility that can shape (or misshape) the Radio Frequency (RF) environment. Because these areas do exist within a building or on campus, the Mobile UC application must be able to accommodate for this situation in providing the best voice quality.

With location-aware roaming, dead zones become a major problem because this technology doesn’t have the intelligence to roam to cellular when a phone passes through one of these dead zones. Roams that are solely dependent upon on location-based logic will fail because, in a dead zone, the current Access Point (AP) would have no associated location-mapping and the client would assume it was within a contiguous WiFi space. In this case, the WiFi signal could go to zero without a guarantee of cellular coverage and the call would drop. By the time you enter a “dead zone”, it’s too late.

Environment-Aware: In contrast, an environment-aware solution like DiVitas responds dynamically to changes in the RF neighborhood. It constantly monitors voice quality and will automatically roam to cellular-mode if the WiFi call degrades, regardless of the user location. Dead zones are not a problem in an environment-aware solution like DiVitas; they are just a normal cause to roam to cellular.

OVERLAPPING CHANNEL CONFLICT

Location-Aware: APs often experience overlapping channel conflict - an occurrence that happens when two APs configured to the same channel are located side-by-side. When this happens they can either null each other’s signal out or induce interference, blocking communication. Again, as with dead zones, a location-based solution is not able to roam to cellular when it experiences a loss of signal so the call will drop.

Environment-Aware: In contrast, an environment-aware solution such as DiVitas detects any loss of WiFi signal or degradation of voice-over-WiFi quality. In either of these situations, it will automatically roam to cellular. This means calls won’t drop.

Antenna Sensitivity

Location-Aware: Many location-aware solutions don’t properly account for antenna sensitivity differences between devices. This means one phone may pick up a WiFi signal that another phone cannot, and the phone with the weaker signal will fail to roam to cellular. Or it might roam at an inappropriate time … like when it shouldn’t. (Spending more time in cellular means more money spent on cellular minutes). This muddies the concept of location-aware roaming because the ability to receive the signal – and place or maintain a phone call – is dependant on where a person (with a handset) is standing in the building relative to an AP, and it depends on the RF-sensitivity of the device. Performing a location service with one device may induce undesirable handover behaviors with other devices…even from the same handset vendor.

Environment-Aware: In contrast, environment-aware solutions detect any changes in signal strength, and automatically roam to cellular when a signal is lost or call quality degrades beyond acceptable.

For more information on DiVitas Networks, please visit our website at www.divitas.com

Beware problems facing Location-aware FMC

We recently received the following comment/questions (see FMC, Mobile Unified Communications & DiVitas) following one of our posts:

I recently read an article with one of your competitors claiming their technology "takes advantage of location." The implication was that other FMC vendors don’t do this and so now I’m curious to find out more on this topic. I have three questions right now that I’m hoping you can answer.

1-Does DiVitas offer location-aware services?

2-If not, why not?

3-What do you offer instead (and how is it different/better)?

I am a VoIP purchasing decision-maker at a major provider network (healthcare) and planning an FMC deployment in the near future. But I’ll confess that I’m having a hard time convincing myself this location-aware thing is really “real”, much less a deciding factor when choosing among FMC vendors.

DIVITAS RESPONDS:

By Rich Watson

Basically, a location-based service is implemented to discover the “edge” of the WiFi network coverage. Within a company facility, WiFi access points are positioned to ensure wireless accessibility while the user is inside the building (or on the campus). Once outside of a company facility (off premise), mobile communications services must rely on cellular coverage. FMC embodies the concept that allows a user to roam from a WiFi network into a cellular network without dropping the call (and in reverse). With a location-based system such handovers are triggered by a user passing beyond a marked edge Access Point.

DiVitas does not offer a location-based solution, but for a very specific reason. While the concept is appealing, location-based solutions are faced with several operations challenges in providing smoother WiFi-cellular roaming. The base presumption is that once installed, the coverage map of the WiFi doesn’t change. The building “exit” location is manually mapped regarding the near Access Point ID and signal strength at that point. As long as nothing is changed that affects the RF characteristics in that area, things are fine. However, adding new Access Points, changing transmit power, or even moving office cubicles or filing cabinets around may change the RF coverage! With any such changes, the location-based information must be manually re-configured, and it must be closely monitored and managed.

There are reasons to roam to cellular beyond just crossing the edge of the network. Any time the voice connection viability is jeopardized by RF congestion or interference, a roam to cellular should be invoked. For example, a wireless voice connection may be initiated when the signal strength is strong and congestion/interference is low. But if a high-bandwidth wireless application is launched, those RF characteristics radically change and will deteriorate the experienced voice quality. At this point, the handset should roam to cellular, even though the user is located well within the bounds of the WiFi coverage area, in order to ensure maximum call quality.

DiVitas has taken a more reliable approach to implementing cross network management: environment-aware services. DiVitas has implemented this sophisticated architecture to always ensure that the user has the very best voice quality experience by monitoring the total RF environment in order to make roam decisions. Because RF can be dynamic, irrespective of location, being able to respond to the real-time RF changes provides DiVitas a real advantage over location-based solutions and obviates any manual configurations of the location maps.

FMC lets you make a do-it-yourself hotspot

By DiVitas Chief Blogger

So it wasn’t just me. Apparently everybody at DiVitas got the “I’m high on life!” call from David today. This I learned during the afternoon blog meeting.

David is a sales guy, and he’s very animated (as sales guys tend to be). So when he’s amped up, he makes sure everybody knows about the cool thing responsible for getting him to his happy place. Today’s big event? David was able to place cheap, high-fidelity-sounding calls to us DiVitians from the comfort of his hotel room (yes, David was on vacation in St. Kitts and thousands of miles away during this flurry of phone calls. Like I said – animated …)

Today was my first time hearing about this “do-it-yourself-mobile-hotspot” trick, and I definitely plan to check it out the next time I travel. David brought a portable Linksys access point (AP) from home and simply hooked it up to the Ethernet cable in his hotel room. Voila! He created a mobile-hotspot for himself. Suddenly his laptop could be on the Internet and he could make WiFi calls using his DiVitas phone – all at the same time.

With this little setup, David was able to call everybody at DiVitas (which I think he literally did) and it didn’t cost him a cent. Because he was using WiFi, he didn’t use any mobile minutes. And he avoided those nasty international roaming fees (that can quickly off-set any coin saved on a low-season travel package.)

The bottom line: It can pay to bring your work phone on vacation (that is, if it’s DiVitas). Phoning home with DiVitas is as inexpensive as placing a call from your deskphone because you’re able to use the telephony plan your company set up for long-distance calling.

If only ET had a DiVitas phone. He would have been able to phone home more quickly (and cheaply!)