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“HaLow” sets stage for multi-channel Wi-Fi

The Wi-Fi Alliance’s announcement of the low power version IEEE 802.11ah, dubbed “HaLow”, was dismissed by some analysts as being too late to make a significant impact in the fast growing Internet of Things (sector). That view is wrong and seriously discounts the power and momentum behind Wi-Fi, to the extent that HaLow has already received extensive coverage in the popular as well as technical press. It is already far closer to being a household name than other longstanding contenders as wireless protocols for IoT devices such as Zigbee and Zwave.

It is true that certification of HaLow compliant products will not begin until 2018, but with IoT surging forward on a number of fronts including the smart car, digital home and eHealth, SoC vendors such as Qualcomm are likely to bring out silicon before that. There are good reasons for expecting HaLow to succeed, some relating to its own specifications and others more to do with the overall evolution of Wi-Fi as a whole.

Another factor is the current fragmentation among existing contenders, with a number of other protocols vying alongside Zigbee and Zwave. This may seem to be a reason for not needing yet another protocol but actually means none of the existing ones have gained enough traction to repel a higher profile invader.

More to the point though HaLow has some key benefits over the others, one being its affinity to IP and Internet through being part of Wi-Fi. Zigbee has responded by collaborating with another wireless protocol developer Thread to incorporate IP connectivity. But HaLow has other advantages, including greater range and ability to operate in challenging RF environments. There is already a sense in which the others are having to play catch up even though they have been around for much longer.

It is true that Bluetooth now has its low energy version to overcome the very limited range of the main protocol, but even this is struggling to demonstrate adequate performance over larger commercial sites. The Wi-Fi Alliance claims that HaLow is highly robust and can cope with most real sites from large homes having thick walls containing metal, to concrete warehouse complexes.

 

The big picture is that Wi-Fi is looking increasingly like a multi-channel protocol operating at a range of frequencies to suit differing use cases. To date we have two variants, 2.4 GHz and 5 GHz, which tend to get used almost interchangeably, with the latter doubling up to provide capacity when the former is congested. In future though there will be four channels, still interchangeable but tending to be dedicated to different applications, combining to yield a single coherent standard that will cover all the basses and perhaps vie with LTE outdoors for connecting various embedded IoT and M2M devices.

HaLow comes in at around 900 MHz, which means it has less bandwidth but greater coverage than the higher frequency Wi-Fi bands and has been optimized to cope well with interference both from other radio sources and physical objects. Then we have the very high frequency 802.11ad or WiGig standard coming along at 60 GHz enabling theoretical bit rates of 5 Gbps or more, spearheaded by Qualcomm, Intel and Samsung. WiGig is a further trade-off between speed and coverage and it will most likely be confined to in-room distribution of decoded ultra HD video perhaps from a gateway or set top to a big screen TV or home cinema.

Then the 5 GHz version might serve premium video to other devices around the home, while 2.4 GHz delivers general Internet access. That would leave HaLow to take care of some wearables, sensors and other low power devices that need coverage but only modest bit rates. As it happens HaLow will outperform all the other contenders for capacity except Bluetooth, with which it will be on much of a par.

 

HaLow will be embraced by key vendors in the smart home and IoT arena, such as Paris based SoftAtHome, which already supports the other key wireless protocols in its software platform through its association with relevant hardware and SoC vendors. SoftAtHome can insulate broadband operators from underlying protocols so that they do not have to be dedicated followers of the wireless wars.

AirTies is another vendor with a keen interest as one of the leading providers of Wi-Fi technology for the home, already aiming to deliver the levels of coverage and availability promised by HaLow in the higher 2.4 GHz and 5 GHz bands. It does this by creating a robust mesh from multiple Access Points (APs), to make Wi-Fi work more like a wired point to point network while retaining all the flexibility of wireless.

 

All these trends are pointing towards Wi-Fi becoming a complete quad-channel wireless offering enabling operators to be one stop shops for the digital home of the future, as well as being able to address many IoT requirements outside it.

At the same time it is worth bearing in mind that the IoT and its relative M2M is a very large canvas, extending to remote outdoor locations, some of which are more far challenging for RF signals than almost any home. In any case while HaLow may well see off all-comers indoors, it will only be a contender out doors in areas close to fixed broadband networks. That is why there is so much interest in Heterogeneous Networks (HetNets) combining Wi-Fi with LTE and also why there are several other emerging wireless protocols for longer distance IoT communications.

One of these others is Long Range Wide Area Network (LoRaWAN), a low power wireless networking protocol announced in March 2015, designed for secure two way communication between low-cost battery-powered embedded devices. Like HaLow it runs at sub-GHz frequencies, but in bands reserved for scientific and industrial applications, optimized for penetrating large structures and subsurface infrastructures within a range of 2km. LoRaWAN is backed by a group including Cisco and IBM, as well as some leading Telcos like Bouygues Telecom, KPN, SingTel and Swisscom. The focus is particularly on harsh RF environments previously too challenging or expensive to connect, such as mines, underwater and mountainous terrain.

Another well backed contender is Narrowband-LTE (NB-LTE) announced in September 2015 with Nokia, Ericsson and Intel behind it, where the focus is more on long range and power efficient communications to remote embedded sensors on the ground. So it still looks like being a case of horses for courses given the huge diversity of RF environments where IoT and M2M will be deployed, with HaLow a likely winner indoors, but coexisting with others outside.

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Operators unhappy over Wi-Fi and unlicensed cellular coexistence plans

Controversy has raged for well over a year now over plans by some mobile network operators (MNOs) to extend their spectrum into unlicensed 5GHz bands currently occupied by Wi-Fi. The arguments have been both commercial and technical, centering on the rights of MNOs to compete with established Wi-Fi networks and at the same time the efficiency or fairness of mechanisms for coexistence between the two.

LTE-U enables 4G/LTE cellular services to be extended into the 5GHz unlicensed bands, which is obviously attractive for MNOs because it gives extra precious spectrum without having to pay for it while making it easier to support high bandwidth applications like premium live video streaming. But the initiative, initially proposed by Qualcomm and Ericsson, has gained some traction within the 3rd Generation Partnership Project (3GPP) primarily because many MNOs want to gain full control of heterogeneous networks combining licensed and unlicensed spectrum, so there is a major commercial force here.

MNOs have expressed frustration over Wi-Fi offload, which is necessary to avoid overload on their networks and give their subscribers the best quality experience, but means they have less control over end-to-end traffic. Not surprisingly though those Telcos with extensive Wi-Fi hot spot networks take a different line and are opposed to LTE-U. Therefore we find that operators like AT&T and BT with huge investment in Wi-Fi hotspots but smaller presence in cellular are opposed to LTE-U. On the other hand Telcos that have not bet so much on Wi-Fi but have major cellular operations now support LTE-U, including big hitters like Verizon, China Mobile, NTT DoCoMo, Deutsche Telekom and TeliaSonera.

Notably though some of the world’s biggest providers of mobile services are ambivalent about LTE-U, which some of them see as complicating rather than simplifying the drive towards heterogeneous services combining licensed and unlicensed spectrum. The view there is that Wi-Fi is best placed to occupy the unlicensed spectrum with a lot of momentum and investment behind it. The LTE-U camp counter that the technology can carry twice as much data as Wi-Fi in a given amount of 5 GHz spectrum through use of carrier aggregation via LTE-LAA. This was already defined in the LTE standards and enables multiple individual RF carrier frequencies, either in the same or different frequency bands, to be combined to provide a higher overall bit rate.

This may be true as far as it goes but is largely irrelevant for users wanting to access broadband services in their homes or public hot spots, according to the Wi-Fi community, a view shared by some MNOs as well. Birdstep, a leading Swedish based provider of smart mobile data products enabling heterogeneous services combining cellular and Wi-Fi, argues that the story is not just about the wireless domain itself but also the backhaul infrastructures behind it. Any spectral efficiency advantage offered by LTE-U would be more than cancelled out by inherent inefficiencies in the backhaul. By offering access to the world’s broadband infrastructures Wi-Fi offers greater overall scale and redundancy.

Another Wi-Fi specialist, Turkey based AirTies, contends that LTE-U is just a spectrum grabbing bid by MNOs and should be resisted. Air Ties has developed mesh and routing technologies designed to overcome the problems encountered by Wi-Fi in the real world and these are only going to get worse as unlicensed spectrum reaches even higher frequencies. The next generation of Wi-Fi based on the emerging IEEE 802.11ad standard will run in the much higher frequency band of 60 GHz, which will potentially yield a lot more capacity and performance but increase susceptibility to physical obstacles and interference. It will only work with further developments in the sort of intelligent beam forming, meshing and steering technologies that AirTies has invested in.

It is true that LTE-U proponents have worked hard to mitigate any impact of coexistence with LTE-U on Wi-Fi. In Europe and also Japan they were forced to do so anyway by regulations that required LTE-U to adhere to similar rules over fair access to spectrum as Wi-Fi. These rules insist on incorporation of LBT (Listen Before Talk) into LTE-U, a mechanism originally developed for fixed line Ethernet networks where there was a shared collision domain (it was called Carrier Sense Multiple Access or CSMA). Stakeholders that are not in favor of rapid LTE-U deployment point out that in the old Ethernet days before 10BaseT/switching, CSMA proved inefficient when there were to many devices trying to get onto the same collision domain. Total capacity could drop drastically and this issue could be reborn into the wireless world.

The European Union specified two options for LBT, one the scheme called DCF/EDCA already adopted for Wi-Fi standards and a newer scheme known as Load Base Equipment (LBE), differing in the procedure for backing off when detecting traffic in a given channel.

Naturally enough there has been an assumption in the LTE-U camp that any deployments will be safe if they do adhere to the EU’s LBE LBT standard. But this assumption has recently been challenged by CableLabs in a simulation modeling a million transmission attempts on sets of nodes following the EU LBE LBT rules. The EU LBE turned out to scale badly with increased numbers of devices, with growing numbers of collisions. This will only amplify concerns expressed by broadcasters such as Sky, as well as by some major vendors like Cisco with feet in both the Wi-Fi and LTE camps, that LTE-U poses a threat to quality of service for premium video especially.

There are no signs yet of the LTE-U camp giving up on their efforts to infiltrate the 5 GHz domain, arguing correctly that by definition unlicensed spectrum is free for all and cannot be owned by any one wireless technology. But there is a strong case for holding off from LTE-U deployments until further extensive tests and simulations have been carried out to assess the impact on capacity and QoS in real life situations.

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LTE Broadcast 2/5: operators get new revenue options

Now that LTE Broadcast is off the ground following the world’s first session on a commercial LTE network transmitted by Australian operator Telstra, attention has naturally turned to potential use cases and revenue generating opportunities. The initial attraction for cellular operators, once they have a sufficiently widespread LTE network in the target region, is the significant bandwidth saving they will get when streaming popular live video, with the consequent ability to optimise capacity and improve service quality for customers, especially in crowded areas. That is a business rather than a specific use case, but at least one major operator is planning to come out with all guns blazing with the latter from day one.

Verizon Wireless has already confirmed it intends to time its 2014 launch of LTE Broadcast in the US to coincide with one of the nation’s iconic sporting events to use the technology for streaming video in the stadium. This event is now widely believed to be SuperBowl, the annual championship of the US National Football League, to be held in New York on Sunday February 2nd 2014. This could be a big day for establishing LTE Broadcast’s most widely touted use case for broadcasting coverage, replays and associated video around sporting or music events where there are large numbers of people concentrated into a venue or arena. Without LTE Broadcast such content has to be unicast, which would cripple a cell and leave many users unable to access the service, while also causing congestion on the associated backhaul networks.

For operators this use case, live event streaming, offers potential both for cost savings by reducing or avoiding need for network expansion and also for generating revenue in various ways, for example subscriptions, pay per view, pay per event, a seasonal pass, or revenue sharing with content partners. Apart from live event streaming, other interesting use cases are on the horizon under five broad categories: real time video streaming across the whole network, news services, broadcast radio, off peak media delivery and cell based advertising. Real time streaming again offers revenue sharing opportunities, most likely with broadcasters or pay TV operators as the mobile part of their TV Everywhere strategies, perhaps combined with Wi-Fi hot spots. Already Verizon Wireless is in talks with US cable operators along these lines. Then for news services, LTE Broadcast has the potential to extend the scope of existing offerings by delivering news and sport as live updates or clips. There is the option of combining these with personalized lower bandwidth unicast services, such as specific stock updates.

These news services could be given away free as part of a premium offering to extract higher subscriptions, or could be advertising driven. The broadcast radio category is also creating some interest as a way of saving unicast capacity while again creating scope for upselling to premium packages and carrying advertising, as well as revenue sharing with providers of content such as music. Then the off peak delivery use case brings a range of opportunities, especially perhaps for tablets as they have greater storage capability, turning them into mobile DVRs (Digital Video Recorders). TV shows, movies, YouTube videos and newspapers could all be drip fed to devices this way, as could software updates. Apart from saving bandwidth this has pay per view opportunities as well as revenue sharing. Finally cell based advertising can be used to deliver ads targeted on the basis of location rather than personal preferences, with live events themselves being an obvious case, but also shopping malls and airports where particular retail outlets or restaurants might want to advertise to mobile users while in that vicinity.

This can be achieved by partitioning LTE Broadcast on a cell by cell basis, so that separate content would be sent to each cell. Most of these use cases are unlikely to be deployed in the immediate future as they will have to wait for widespread availability of devices compatible with LTE Broadcast, which will not be until well into 2015 at least. Meanwhile though some questions are arising, such as how LTE Broadcast will affect Wi-Fi expansion.

There has been interest in Wi-Fi broadcast as well for live events, with Cisco already offering this with its StadiumVision mobile app, which users can download at venues to access event specific broadcast streams over Wi-Fi. This could well compete with LTE Broadcast for live events streaming, but that is another story. Part one in this series is here and part three is here.

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LTE Broadcast 1/5: live debut heralds battles with Wi-Fi to come

The first live LTE Broadcast session delivered recently by Telstra in Australia raised the natural question of why things should be different this time.

The recent history of cellular communications is littered with the skeletons of mobile broadcast’s dismal past, with Telstra’s demonstration as it happens coinciding with the death of the last DVB-H service in Poland. Other notable mobile broadcast failures include Qualcomm’s MediaFLO in the US, which is significant in that the company is now strongly backing LTE Broadcast. Qualcomm’s chipsets are at the center of Ericsson’s LTE Broadcast platform used by Telstra for its live demonstration that served various devices with concurrent video feeds, including a sports match replay, general news and a large video file over the single LTE Broadcast channel.

The same Ericsson/Qualcomm platform will be used in a much more significant test of LTE Broadcast by Verizon at the 2014 SuperBowl in early February 2014. As the most popular US sporting event this will be the perfect springboard for LTE Broadcast, giving it the chance to demonstrate its ability to serve large numbers of users with concurrent streams within a single 4G/LTE cell. This would not of itself prove the case for LTE Broadcast, given that its predecessors could also deliver concurrent streams to multiple users. That after all is the whole point of mobile broadcast. Yet there are important differences this time that suggest LTE Broadcast will at least be a contender for delivering mobile video.

One big difference is that there are now eligible handsets for viewing video, notably tablets but also larger smartphones and a host of emerging hybrid devices that have got consumers hooked onto mobile video consumption when they weren’t before.

The other big difference now is the backing of key industry players and the fact that LTE Broadcast, or more precisely the eMBMS (Multimedia Broadcast Multicast Services) technology on which it is based, is an integral part of the LTE ecosystem underpinning current and emerging 4G cellular services.

All the big industry hitters, including Alcatel-Lucent as well Ericsson and Qualcomm, are full square behind it, along with a host of key second string infrastructure vendors like MobiTV. DVB-H was also an open standard but it required significant additional infrastructure investment to deploy, as well as specific upgrades to handsets. LTE Broadcast will run in principle over all LTE infrastructure and while it is not supported by current commercially available handsets, it will come out of the box with the next generation.

Qualcomm's Mazen Chmaytelli, senior director of business development at its Labs, is on record saying he expects the first LTE Broadcast capable handsets to come to market in the second half of 2014. For these reasons LTE Broadcast will be quite widely deployed, with AT&T as well as Verizon Wireless planning to do so in the US, while Korea Telecom is collaborating with Samsung towards a launch in South Korea. In Europe France Telecom’s Orange and EE have announced firm intentions to deploy LTE Broadcast.

Yet at one time there was equal momentum behind DVB-H and despite the fact LTE Broadcast is much better placed its success is still not a done deal. One reason for that is the advance of Wi-Fi, which may enable venues to cater for large scale events more cost effectively through temporary deployment of hot spots. At the same time versions of existing digital terrestrial standards, such as the DVB’s T2 Lite, could be better placed to meet the requirement for general mass delivery of video to mobile devices. There is a good reason for this.

Outside major events such as Super Bowl where large numbers of people will be consuming the same video streams such as sporting action replays, there will not often be more than a handful of people watching the same content in a single cell and often it will only be one. In the latter case LTE Broadcast collapses to unicast. Yet at any given time there may well be a number of people watching different streams in a given cell, so there is still a need for an efficient video delivery infrastructure, which DVB T2 Lite would be as it has a much larger coverage area than an LTE cell. Within the much larger digital terrestrial coverage area, even mid-tier content would often by consumed concurrently by several people, so that mobile broadcast would save a lot of spectrum. Mobile operators such as EE have stated that the initial “monetization motive” for deploying LTE Broadcast will come from more efficient delivery of video both over the backhaul networks and at the radio level inside cells.

My contention is that these efficiency savings will not materialize outside major events. Even within such events, Wi-Fi may be a more cost effective way of addressing the “Super Bowl” effect and could be offered as a service by mobile operators, which would benefit by offloading the traffic directly onto the more efficient fixed broadband infrastructure. On this count there are already a variety of products available, for example from Birdstep in Sweden, which enable automatic selection of traffic for offloading to Wi-Fi according to specified business rules.

With some operators already talking about temporary LTE Broadcast channels for venues as a future business model, it will be interesting to see how this approach will stack up against Wi-Fi and the answer may be not very well. At least with the upcoming Verizon demonstration at Super Bowl 2014, the battle lines are being drawn. Part 2 is here.

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Getting The Full Download On DataOffload: Pre-MWC13 Exclusive With Birdstep Technology

www.birdstep.com

In the run-up to MCW 2013, we interviewed Lonnie Schilling, newly appointed CEO of Swedish software company Birdstep Technology, that provides smart mobile connectivity and security solutions.

CTOIC: What do you see as the key theme for MWC in 2013?

Lonnie: Well as in previous years, there are going to be many themes in 2013, but a reoccurring theme, and perhaps the greatest challenge for operators is keeping up with subscriber demand, staying ahead of the bandwidth curve driven by more video rich content and ensuring a compelling user experience for a wider demographic customer base.

CTOIC: How have operators been responding?

Lonnie:  Not always in the best way! It seems that data caps have come back into play, but this is wholly counterproductive and fails to take account how customers want to use their mobile phones. Mobile subscribers are consuming more and more data and watching longer forms of video but these caps are self-defeating in such that customers believe that consuming data implies incurring punitive charges or data throttling which make the service non-compelling. So the real challenge for operators is to come to grips with complementary technologies like Carrier WiFi and Smart Data Offload solutions, and align this with their business needs to meet the requirements of their subscribers.

 CTOIC: But hang on, I thought LTE/4G was supposed to solve this bandwidth crunch?

Lonnie: Yes LTE does bring efficiencies over 3G and certainly more bandwidth, but the business case for the necessary coverage and density is prohibitively expensive. Here too Carrier WiFi is being used as a cost efficient solution for offloading. MNO's are now beginning to take advantage Smart Data Offload solutions to selectively offload non-premium data, perhaps a YouTube video, to WiFi while keeping premium data, such as a video subscription service like Netflix or Webex on the cellular core to leverage existing Subscriber Management services. In addition to smart selective offload, the MNO is interested in using subscriber analytics to better understand the Customer Experience from the perspective of the handset. The analytics give insight into what services are being consumed over WiFi and cellular, where the subscriber is when they consume the services and the quality of the service is, both objective and subjective. This resolves a key concern MNO's have had with WiFi; the operator now has complete visibility of the subscriber and service whether the user is on cellular or WiFi.

CTOIC: Presumably you agree LTE/4G does at least scale to the higher bandwidths required for emerging services, even if the costs are high?

Lonnie: I would argue that LTE has not kept up with the bandwidth curve. Just look at how smartphones are being used to consume more video. Did you know that it is expected that 2/3 of the world’s mobile data traffic will be video by 2016 or that globally, the average mobile connection will generate 1,216 megabytes of mobile data traffic per month in 2016, up 1,221% from 92 megabytes per month in 2011, a CAGR of 68%! This trend shows that the rate at which data consumption is growing, continues to outpace the rate at which mobile technology, including LTE, can deliver bandwidth. So here’s the telling data point, LTE gives us roughly 12x increase in bandwidth over 3G, but bandwidth growth over the period since LTE began development has gone up 30x. And, according the Cisco, the problem further exacerbates over the next few years. LTE is behind the curve when the market is demanding greater bandwidth.

CTOIC: So what is the answer?

Lonnie: I believe MNO’s must be more pragmatic about augmenting their mobile service offering with Carrier WiFi, in conjunction with Smart Data Offload solutions. By deploying an intelligent offload solution, the MNO can become much more innovative in how they package and tariff the service and effectively compel their customers to consume more instead of less. By associating network policy with the intelligent offload solution, the MNO decides which applications will be transported via cellular or WiFi determined by time-of-day, location, quality of connection or user policy profile. The point is that the MNO can be completely agnostic to the access medium for a greater aggregate RAN capacity, or develop innovative business models for maintaining premium traffic on the cellular and non-premium traffic over WiFi. Standards such as Hotspot 2.0 and ANDSF enable the automated network discovery, selection and security, as is done today in cellular networks. Then link this to the ability to have real-time active / passive analytics for the MNO to maintain a very clear perspective of the customer experience, even when using WiFi, and the MNO maintains the control of the experience associated with their brand and offering. It is not a huge leap in faith to foresee in the very near future that a customer can globally roam and handoff between cellular, WiFi and back to cellular based on a defined network policy.

CTOIC: How quickly do you anticipate this happening?

Lonnie: It’s already begun! But fact is that it will happen much faster than it did for the cellular industry, which took 30 years to get to where we are today with transparent international roaming where subscribers are unaware of all the transactions between operators taking place in the background. All that complexity is completely shielded from the user even though their own handsets are participating in the transactions. I believe the “Law of Accelerated Returns” tells us that it may be up to an Order-of-Magnitude less time than it took for cellular. Besides, the hotspot infrastructure is already there or under construction, and of course the industry understands well how to develop and negotiate roaming agreements.

 CTOIC: Presumably cellular operators will not offload all their data. What data will they keep on their own infrastructures and how will that decision be made?

Lonnie: That will vary between service providers. But one thing they will all want is the ability to make intelligent decisions in real time over what data to move according to business rules and perhaps traffic conditions. Those decisions will be made by policy and executed in Smart Offload software that understands the subscriber, the data, the location and time-of-day and can offload according to specified rules.

CTOIC: What might those business rules be?

Lonnie: A service provider network might be getting a lot of You Tube traffic that is filling up the cellular network, and that could be offloaded to Wi-Fi. But say that operator has a contractual relationship with another OTT provider like Netflix that requires guaranteed QoS and the ability to monitor the activity. Then Netflix traffic would be kept on the cellular network and use the subscriber management capabilities there.

CTOIC: How will Wi-Fi be integrated with cellular?

Lonnie: That is still subject to debate. There are various options on the table, with some advocating running Wi-Fi in parallel with the cellular infrastructure and others who believe cellular and WiFi to be converged in the Packet Core. Regardless of the level of integration, I think it likely that operators will want to adopt a hierarchical structure where WiFi is implemented into the small-cell architecture and provides bandwidth and coverage in high-density venues and in-doors.

 CTOIC: Thanks Lonnie, let’s see what MWC 2013 has to answer in this debate.

During Mobile World Congress 2013, Birdstep is located in hall 7, E80, within the Swedish Pavilion

Lonnie Schilling
Chief Executive Officer, Birdstep Technology

Lonnie Schilling

Schilling brings 20 years of experience of equity investment, strategic business development, architecture sales and marketing within the international communications market. He was most recently Director, Mobile Service Provider Sales & Business Development at Cisco and he has also held leading management positions in other global companies such as Motorola, ITT, Worldview Technology Partners, Bolt Beranek and Newman (BBN). Schilling holds a B.S. in Computer Science from the University of Maryland. He completed graduate and postgraduate studies at the Swiss Federal Institutes of Technology, the International Institute for Management Development, INSEAD and the Marshall School of Business at USC.