© Springer-Verlag London Ltd Virtual Reality (1998) 3:147-156

Wearable Computers: Information Tool :for the Twenty irst Century K. L. Jackson, L. E. Polisky SENTEL Corporation, Alexandria, Virginia, USA Abstract: The wearable computer is a portable computer that is actually worn on the user's body. Ergonomics is therefore a vital feature of its design. Since humans naturally communicate with voice, a wearable computer also responds to the voice. Wearable computers and global wireless networks make it possible to bring exciting capabilities to the individual. Until recently, wearable computer development has been restricted to academic and military laboratories. Now, technological advances and reduced cost have ignited investor excitement about wearable computers. Wearable system applications in manufacturing, logistics, medicine, training, quality control, communications and even entertainment are now becoming widespread. The earliest development of wearable computers occurred in the ~960s. All of the elements of the modern wearable computer were in place in the Eudaemons system for predicting outcome on a roulette wheel Since then, wearable computer development has paralleled advances in microprocessor technology. After addressing the important distinction between wearable and mobile computers, this paper will look at wearable computers as an information tool for industry. A short history of wearable computers will trace development from the early single application attempts to today's featurerich systems. A discussion on current and anticipated applications is then followed by an overview of important related technologies. Finally, the paper will assess how wearable computers could impact twentyfirst century industry and society.

Keywords: Wearable computer; Information tool; Mobile computer; Wireless networking; Voice recognition

Introduction Modern information systems bring new efficiencies to the organisation by enabling rapid retrieval, processing and dissemination of recorded information. Wearable computers and global wireless networks make it possible to bring those same efficiencies to the individual. This fact could be the spark that igniEes the 'New' Information Age. Even more exciting is that this tool can now be an always-ready adjunct to our amazing biological processor- the brain.

Until recently, wearable computer development has been restricted to academic and military laboratories. A few high-technology companies then began applying this technology to industrial processes and information retrieval operations. These uses were under reported because of competitive pressures and marginal successes. Promises of 'order of magnitude improvements' were unrealised because hardware and software were unable to implement effectively the exciting new visions. Then 'Moore's Law' finally caught up with these visions. The result was economic incentive and investor excitement about wearable computers.

Wearable system applications in manufacturing, logistics, medicine, training, quality control, communications, and even entertainment are now entering the economy [1]. Once these applications are wedded to the evolving global wireless communications infrastructure, quantum improvements in every conceivable industry will drive our information society. After addressing the important distinction between wearable and mobile computers, this paper will look at it as an information tool for industry. It will then trace the development of wearable computers. Next, system features and common components will be discussed. Current and anticipated applications are presented followed by important related technologies. Finally, the paper will assess how wearable computers could impact twentyfirst century industry and society.

Wearable versus Portable Initially, the idea of wearable computers seems little more than a semantic twist on the more common portable computer. This initial view is easily clarified once a working definition of 'wearable' is established. A device is 'wearable' when one can use the device for its prescribed function while maintaining mobility and without being physically restricted by the device itself. Take hearing aids as an example. The first of these devices resembled metal trumpets (Fig. 1). The owner would put the narrow end to the ear and the speaker shouted into the wide end. These systems were definitely portable, however, the user's hand was restricted while holding the device. 'Wearable' hearing aids were first used in the early 1920s (Fig. 2). Although large, heavy, and very obvious, they were a big improvement over the ear trumpet. A wearable computer provides the same function as the portable computer without the physical restrictions imposed by needing to hold the device with your hands or being restricted to using an external platform (i.e. table) to support the system.

The Information 'Tool'

Fig. 1. The ear trumpet, a 'portable' hearingaid.

Fig. 2. A 'wearable' hearing aid.

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A tool is defined as an instrument to facilitate production. A well-designed tool is used to produce a product or service with a minimal expenditure of time, labour and material. Productivity of mankind remained fairly constant up until the nineteenth century and the industrial revolution that was characterised by the development of labour-saving machinery and mass production techniques. Since the industrial revolution, productivity has increased through the use of improved production machinery and processes and the introduction of the computer. The 'information tool' was used in the 1930s with the development of the first mainframe computers. These were used to influence production but were separated from the actual manufacturing sites. Mechanical computation methods were also developed for use in precision tool works. Automated techniques began to enter manufacturing facilities in the 1960s with electronic counters and controls. More sophisticated mainframe computers also began to assist in the production process. In the 1970s, the microprocessor and integrated circuits made it possible to reduce the size of mainframe computers and increase their capacity. They

became ubiquitous throughout industry, carrying out not only production chores but also the organ isation of administrative functions. In the 1980s, the personal computer (PC) and workstation were introduced. The capacity and capability of these machines rivalled the mainframe computers produced 10 to 15 years earlier. Next, PC networks replaced the mainframes and the first portable computers were introduced. In the 1990s, computers have significantly increased productivity in many arenas. Some cite this as the reason for this decade's economic expansion and prosperity with no associated inflation. Production efficiency gained by the wide use of computers and automated techniques indicate that similar advantages can be gained with increased portability. Tailored software, advanced communications and the wearable computer can now form the ultimate information tool. This combination can lead to quantum leaps in process efficiencies. As part of information age evolution, the wearable computer could become a critical tool for the twentyfirst century economy.

Wearable Computer Development The earliest development of wearable computers occurred in the 1960s. The first system was a cigarette-pack-sized analogue computer with four push-buttons. Invented in 1961 by Ed Thorp and Claude Shannon, this system was used to predict the performance of roulette wheels. A digital microprocessor was later used to 'beat the house' in the "Eudaemon Caper'.

endeavour for this group of brilliant physicists. The formula took into account initial conditions, multiple variables and the differential nature of the motion. It also had to take into account the speed of the wheel, the drop point of the ball, the type of roulette ball and the tilt of the wheel. The calculation had to be made in the brief time between when the roulette ball was dropped and the table betting was closed, less than 1 minute. The physicists knew the only way they could perform the calculation in time was to use an electronic computer. They used the mainframe computer available to them in the physics laboratory to establish the ability of the formulas written to predict the fall of the roulette ball and had success using a second-hand roulette wheel they had purchased for empirical experiments. The next part of the enterprise initiated the birth of the first wearable computer. This was in response to the elements of the problem and the environment where it was to be used. The students determined that they would need a two-person operation in the casino, a better and a computer operator. The hardware they would need would consist of a concealed portable computer and communication system. The portable computer would need an input/output capability so that the computer operator could input the formula's initial conditions and receive the results of the calculation. The communication system selected was a short-range inductive system since the students felt that a RF system was likely to be detected by casino surveillance. The microprocessor computer needed to be programmed with the tailored software for predicting the roulette ball motion. Power had to be supplied by batteries that would power the computer and communication transmitter in the computer operator's equipment and the receiver and indicator equipment in the better's equipment.

The 'Eudaemon Caper' A group of graduate physics students in California reasoned that by using Newtonian motion formulas it would be possible to predict the landing location of a roulette ball and thus produce a windfall payoff at a Nevada casino. The students were motivated by pushing technology forward to accomplish their goal and the adventure of pulling it off in the fortress like atmosphere of a Nevada casino as the financial payoff. The details of this effort are described in a fascinating book written by one of the participants [2]. Writing the motion formulas for the roulette wheel ball was the easy part of the

Fig. 3. The Eudaemon Shoe.

Wearable Computers: Information Tool for the Twentyfirst Century

The indicator equipment was a set of three solenoids which each had three vibration levels of response, slow, medium and fast, providing nine distinct outputs which corresponded to the nine octants of the roulette wheel. All of the hardware, batteries and interconnecting wires had to be concealed in the clothing of the computer operator and the better. The better's equipment was concealed in a shoe that contained the batteries, the inductive receiver and the set of solenoids that provided a vibrotactile display (Fig. 3). All of the elements of the modern wearable computer were in place in the Eudaemon system. The system contained wearable cQmponents that included a microprocessor with tailored software, an operator interface, a display and a communication system. After years of testing, dry runs, redesign for operational and ergonomic reasons and other modifications, the system was used for its designed purpose with some degree of success. The amount of money won was not reported or quantified but the true success of the effort can not be measured in a statement of profit and loss. The success was really in the development of a computer application that was years ahead of its time, the adventure undertaken by a group of truly creative scientists and their friends (the Eudaemons) and what they were able to accomplish.

Rapid WearableComputer Development Wearable computer development has paralleled advances in microprocessor technology These chips now require less power and space than previous computer-chips and have greater processing and memory capability. US Department of Defense interest (in the form of research grants) and industry participation has spurred rapid development in microelectronics at many academic institutions. In 1980, a system design by Mann [3] used a backpackmounted Apple II computer to control photographic equipment. In 1983, Taft commercialised a Z~80based, toe-operated computer for counting cards in blackjack. By 1990, Maguire and Ioannidis were leveraging spread-spectrum radio links in the IBM/ Columbia Student Electronic Notebook Proiect [4]. The Defense Advanced Research Projects Agency (DARPA) has also been a real force in the early development of this field. DARP,~s efforts have involved the development of field-wearable communication and computing devices for improving military

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fighting capability and the care of wounded personnel. Interesting partnerships have been created in this field between behavioural scientists, psychologists, engineers, software developers, system integrators, component developers and manufacturing entities. The 1990s have seen explosive growth in this field. In October 1997, the First International Symposium on Wearable Computers was held in Cambridge, Massachusetts and developments in this new computer field were described to the world. There were 385 individuals who registered for the symposium and 18 exhibitors.

Wearable Computer Characteristics The wearable computer is a poriable computer actually worn on the user's body. The computer can be worn next to the skin or on the outside of clothing. This location choice may be a matter of the function of the computer. Proximity to the skin will allow the monitoring of the user's biological functions and will provide an indicator system via tactile sensation on the skin. Awell-designed system will evenly distribute the weight of the system, will provide all user interfaces in a convenient form and will allow the user full freedom of motion so that normal activity while wearing the computer is possible. All wearable digital computers contain a CPU, battery power supply, user interface for inputs and control, and an indicator system. Wearable systems can be designed to carry out narrow, specific tasks or they can serve as a general computing device.

Ergonomics The human engineering of the wearable computer is a vital feature of its design. It should become an extension of the user's mental and physical capability and remain unobtrusive to normal human activities. Since humans naturally communicate with voice, a wearable computer should respond to the voice. The hands, which are normally used for performing tasks, are not restricted by a well-designed wearable device. The simple act of donming the wearable computer should be as easy as putting on an article of clothing. It should be comfortable, capable of long-term wear and not restrict the user's mobility. The equipment must be intrinsically safe to the user and to nearby equipment or personnel. Input and

control functions must be easy and intuitive. Output displays must be easily read and understood.

Wearable Computer Components Wearable computer components are similar to their portable computer counterparts except for ergonomic requirements. In general, components are smaller and lighter. Visual display devices tend to be head-mounted although some flat-plat designs are available for placement on the forearm. Audio or vibrotactile devices have also been used for input and output. By interfacing directly with the human senses of hearing and touch, these interfaces are natural and easily used.t2] Ergonomics is critical to good wearable design. Additional components include: •

Input/output devices -

mouse (pointing device)

-

miniature keyboard

-

specialised keypad

-

voice recognition

-

biological sensors

- global positioning system (GP5) -

•

video cameras

Power source -

batteries

- solar cells

Fig. 4. XybernautMobile AssistantTM. Xybernaut TM wearable computer. This system features a Pentium 133 MHz CPU, integrated pointing device and head-mounted display (HMD). (It should be noted that the next generation Xybernaut TM wearable has a faster CPU). Batteries are worn on a belt around the waist, The HMD integrates a monitor, microphone and speaker into a light head worn device. The microphone and speaker provide for audio input and output. This can be used for voice driven applications or for voice communications. Wireless access to local networks is accomplished using a standard PCMCIA wireless LAN card. The headgear could also hold a miniature video camera. The HMD and CPU are interconnected via a cable. ViA Incorporated produces a wearable system based on a unique flexible motherboard (Fig. 5).

- human body currents [5]

Additional Features Recent advances in mobile communications technology have made 'wearability' an important feature. Hands-free computing capability and ubiquitous data access provide greatly enhanced capability to an individual. Device micro-miniaturisation and microprocessor advances are driving energy requirements down and system capability up. In the near future, low Earth orbit satellites could provide worldwide Internet access to body worn systems. This promises greatly enhanced network computing capability and real-time audio and video communications.

Commercial Wearable Systems Currently there are only three wearable computer systems available commercially. Figure 4 shows the

Fig.

5.

ViA

wearable

TM.

Wearable Computers: Information lool for the Twentyfirst Century

In this system, the computer is part of the belt and wraps around the user's waist. Audio microphones and speakers are also available for input/output operations. Hard card mass storage and a handheld flat-plat display complete this wearable system, The most recent wearable computer to enter the commercial marketplace is the Mentis TM from Interactive Solutions (Fig. 6). This system is designed for high-end multimedia applications and features a modular assembly consisting of three separate, attachable sections: the processing unit, the universal utility bay and the battery pack. The utility bay is used for insertion of rotating storage media such as CD-IRQM, DVD or a second hard drive. The Mentis T~ has already been used for instantaneous foreign language translations, fault diagnosis and 'just-in-time' training. All three of these systems have multiple configurations and options. They can also be used with many different head-mounted or hand-held displays.

Wearable Applications Wearable computers have been used for wiring installation (Boeing) [4], maintenance (United States Air Force) [6], machine tool production [7], quality control [8] and law enforcement [9]. Each of these applications used task-specific software for increasing efficiency and reducing paperbased records. Although successful, these efforts were considered experimental because of the unique computer technology, Over the next few years, wearable computer use should grow exponentially. This will be driven by the advent of powerful

Fig. 6. The Mentis wearable~M.

K. L. Jackson, L. E. Polisky

general-purpose wearables and rapid software development technology. Many other wearable applications have been conceptualised and demonstrated. New and better components are being quickly developed. Wireless communications are becoming more robust and cost effective, The entry of system integrators into the wearable market should herald fast growth in the industry. As wearable computers becQme common tools in commerce, entrepreneurial wearable pioneers will become a strong force in the larger computer industry.

Military Applications The US Department of Defense Advanced Research Program Agency has been an ongoing sponsor of research in the wearable computer field. Their sponsorship has addressed two broad areas: (1) Battlefield effectiveness of the individual, and (2) Military support operations. The wearable computer increases battlefield effectiveness by providing current intelligence information. This enhances observation quality capability and extends the military intelligence network down to the individual. This is accomplished without sacrificing mobility or fighting capacity. Military support is improved through added efficiencies in maintenance, operations, personnel causality monitoring, search and rescue, logistics and training, The wearable computer increases military capability by applying information as a force multiplier to the individual soldier. While connected to the military communications network, situation awareness is increased and common battlespace view is assured. Data collection and dissemination is equally enhanced. Two-way data communications could also provide on-scene video and audio from tactical units. Search and rescue operation would also be enhanced in the event of injury or separation from the force. The US military needs to be more efficient and effective. Reductions in personnel, however, mean that fewer people must accomplish more. This is true in spite of more sophisticated weapons and more complex operations. To overcome this paradox, advanced technology must be applied to the problem, Wearable computer technology can help by improving information availability and enabling more effective collaboration between workers. Augmented by knowledge-based applications and ubiquitous access to reference information, personnel

productivity in many military support functions could increase substantially.

Maintenance Senior trained maintenance personnel within the military are at a premium. Through the use of wearable computers and networking technology, their experience and skill can be made available to less experienced maintainers. Through remote monitoring and review, quality control can be enhanced and downtimes minimised. Reference material with accurate information can be immediately made available, Electronic documentation and verification could improve documentation and audit capability. Voice and video technology could provide 'just-in-time training' or immediate expert assistance anywhere.

Causality Monitoring The US military has been experimenting with using wearable computers to monitor and report an individual's medical state, Tele-medicine systems can monitor and transmit heart rate, blood pressure and respiration rate, By responding only to an encoded interrogation signal, vital information is not compromised. 'Combat garments' are also being studied, These garments fit next to the body as an undershirt and consist of a grid of electrically and optically conductive fibres. The grid is woven into normal clothing fibres and is designed for comfort. The conductive fibres are connected to a processor and transmitter. This design monitors biological function such as respiratory rate, heart rate and body temperature regulation. Such a system could also show the ballistic path of a bullet or of shrapnel [1 0].

Military Logistics Improved logistics is a critical key to improved military effectiveness. Wearable computers combined with laser and radio frequency tagging technology can improve inventory procedures. Linked to the military Internet, logistics information would be available to all levels of the US Department of Defense (DoD) hierarchy. This could provide worldwide near real-time accurate status information. Implementation could prevent excessive costs and diminished force readiness caused by erroneous supply decisions, expired consumables and latent logistics information [1 1].

Military Training Wearable computers can be used very effectively in training military personnel for both combat and support roles. Virtual reality displays can simulate various decision scenarios. Wearable computers can generate a broad range of realistic conditions, then time and evaluate the trainee's response. Computer grading of the performance would measure trainee progress.

Commercial Applications Automation and robotics have been used widely in manufacturing and computers are very common in the workplace. Wearable computers though have not caught on quickly. This is due to the failure of wearables to survive the business case. Increased system capabilities and reductions in hardware cost, however, will make the business case compelling in many industries this year This paradigm shift will improve production, maintenance and quality control. The realisation of the general use of wearable computers and its capability to run off-theshelf software greatly reduces the economic cost of this technology. Wearable systems will replace the current laptops and portables and release the worker from current physical restrictions. The health care and entertainment industries could also drive increased use of wearable computers. In health care, patients could be outfitted with biological monitoring devices. Critical patient data could be relayed to a central monitoring station over wireless networks or telephone lines. This data would then be available for immediate observation or archived for patient condition tracking. The computer could also use this information to control patient medication. Virtual reality displays on wearable computer systems could take gaming to the next level. Powerful central processing units could lead to realistic virtual worlds. Collaborative networking and augmented reality displays could eliminate temporal and physical barriers to gaming competition. The multi-billion dollar entertainment industry will eventually perfect sensory immersion technology and spawn even more advanced applications.

Law Enforcement Over the years, law enforcement has effectively used computers. Wearable computers can bring this

Wearable Computers; Information Tool for the Twentyfirst Century

building of mobile LANs. Inexpensive PCMCIA computer cards contain a built-in transmitter and antenna. Although output power is low (0.1 watt), 10@0 feet ranges and 2 MB/second data rates are common. Range can be extended up to 10 miles through the use of access points and directional antennas. Systems with data rates of up to 10 MB/ second are now available. Network communications can also be established using commercial cellular telephone circuits with cellular PCMCIA cards. Although current data rates are restrictive, more advanced techniques promising megabyte throughput will soon be available. Low Earth orbit satellites will also soon provide impressive networking capability.

Voice Recognition Voice recognition developments are especially significant for wearable computer applications. Voice is a natural output medium for people and would relieve restrictions caused by keyboard and pointing devices. Hands-free operations are currently only possible for limited applications. More robust systems are currently being tested. Voice can be used for computer control or for data dictation. Verbal reports could also be given and immediately transcribed for printed display directly entered into a database. Fig. 7. Xybernautwearable used to accessdatabase.

capability to the individual officer. The US Custom Service is experimenting with wearables at the Douglas, Arizona border crossing. There, wearables are used to query databases in the Washington, DC area (Fig. 7) [1 21. Wearable computers could similarly support the officer walking the city beat.

Related Wearable Technologies Wireless Local Area Networks (LANs) Wireless local area networks (LANs) are critical to wearable usage. This assures mobility and constant data access. This technology also enables the

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Video Cameras and Other Sensors Video cameras are now small enough to be installed in a pair of spectacles [1 3]. Used in conjunction with wearables, exciting tele-presence capabilities are possible. A miniature camera can immediately relay visual information to remote observers. Video data can also be routed back to the individual through a fibreoptic cable and a periscopeqike mirror system. This allows the user to observe the video he is recording or to play back previous recorded video. Other sensors that can be used in conjunction with a wearable computer system include chemical and biological detectors, infrared detection, thermal, Iowqight vision goggles, gas sniffers and weapon detectors. The engineering and software necessary for the integration of these sensor devices into a wearable computer are very similar to the integration of the video system.

GlobalPositioningSystem(GPS) The GPS receiver provides wearable computer applications with automated and extremely accurate geographical and timing data. GPS receivers with antenna assemblies can now fit easily into a belt-worn package. Location precision can be enhanced to 1-metre accuracy using differential signal techniques.

The Future of Wearable Computing In the future, the wearable computer will become as common as the ubiquitous PC is today. We postulate that there will be two major designs of wearable computers, one for the workplace and the other for personal use. The workplace unit will be designed to accomplish a specific task or multiple related tasks and will be interfaced with a LAN. The personal unit will be designed to be a labour-saving and lifestyle-enhancing device. They will be designed to interface with the home personal computer. Cellular, digital or satellite telephone will allow complete portability. Wearable computer design will stress comfort and ease of use. Widespread reporting of successful wearable applications will spark the growth of the wearable computer industry. This will be followed by rapidly decreasing cost and an expanded wirelesscomputing infrastructure. Once the wearable computer is accepted as the natural extension of the personal computer, user industries will commit to the product. Mass marketing will capture the imagination of the general public and the wearable computer will become the first hot computer product of the new century.

Wearable Computers in the Twentyfirst Century In the next few years, wearable computers will emerge as a common appliance in society. Their growth will probably mirror that of the PC. Currently, 35% of all homes in the US have a PC. Furthermore, almost every workplace from offices to small stores to factories has at least one PC. This change in society has occurred in the past 15 years.

The University of Tokyo has presented some concepts on the future of wearable computing [1 4]. One of these 'products' is a wearable computing system where digital data is transmitted through clothes, glasses, shoes and belts. By using a 'bodysurface communication system' the computer is distributed across the entire body. Microsized information devices would be located to reduce mechanical shock and improve sensor sensitivity. 'By connecting automatic generators, sensors, input devices and file memories by a Personal Area Network (PAN), walking computer systems will be realised' [13]. In the bio-net system, data transmission methods that use the human body as a cable will be developed. Chemical sensors installed in the human body will observe blood constituents throughout the day and send data to remote sites via wireless transmission [1 41, Wearable computers will be a labour-and timesaving device for industry. The hardware will be mass-produced and the software more robust. Wearable computers will be a common element of the military uniform. Probes built into under garments will monitor biological functions. Wearable systems will produce condition alerts, medication reminders, and track multiple biological functions. Children will be given a wearable for holding vital personal and medical statistics and a GPS-based Iocator system. Society will use wearable computers for recording assignments and appointments, marking key events of the day and linking information to or from their desktop system. Pagers, cell phones and computers will blend into the ultimate information tool for the twentyfirst century.

References 1. Xybernaut Corporation. Proceedings 1998 International Conference on Wearable Computing, 1998 2. Bass1LThe Eudaemonicpie New York: Random House 1986 3. Mann S. An historicalaccount of the 'WearComp' and 'WearCom' inventions developed for applications in 'personal imaging". In: Digestof papers from the First International Symposium on Wearable Computers, Cambridge, Mass, 1997 4. RhodesB. A brief historyof wearablecomputing. 1998 5. Rehmi Post E, Reynolds M, Grey M, Paradiso J, Gershenfeld N. Intrabody buses for data and power. Digest of papers from the First International Symposium on Wearable Computers, 52-55 6. Siegel J, Bauer M. A field usability evaluation of a wearable system. Digest of papers from the First International Symposium on Wearable Computers, Cambridge, Mass, 1997

Wearable Computers: Information Too/ for the Twentyfirst Century

7. RanierD, Manfred W. Mobile approach support system for future machine tools. In: Digest of papers from the First International Symposium on Wearable Computers, Cambridge, Mass, 1997

11. SENTELCorporation. Proposal to Defense Advanced Research Projects Agency, BAA 97-32, Advanced Logistics Program (ALP), Sentinel Automated Material Control System

8. Najjar LI, Thompson JC, Qckerman JJ. A wearable computer for quality assurance inspectors in a food processing plant. Poster presentation at First International Symposium on Wearable Computers, Cambridge, Mass, 1997

12. Johnston M. Xybernaut fashions wearable PC. Federal Computer Week, May 25, 1998

9. SENTEL Corporation. Wearable computer deployment and LAN communication system at United States Custom Agency Facility, Douglas, Arizona, 1997 10. Lind E, Jayarman S, Park S, Raiamanickam R, Eisler R, McKee T. A sensate liner for personal monitoring applications. In: Digest of papers from the First International Symposium on Wearable Computers, Cambridge, Mass, 1997

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13. Mann S. 'Smart clothing': wearable multimedia computing and 'personal imaging' to restore the technological balance between people and their environments, 1998 14. University of Tokyo. Watch-size next-generation Information Devices.Tokyo: University of Tokyo, 1998

Correspondence and offprint requests to: Kevin Jackson, SENTEL Corporation, 225 Reinekers lane, Suite 500, Alexandria, VA 22314, USA. ernaiL kjackson@hqsentel, corn