Hand-held Computing

There has been much discussion regarding the growth and use of hand-held mobile devices and about the effect these technologies will have on our work methods. To understand the effect of mobile devices it is important to understand the state of the technology. Equally influential, however, we should also review the needs for these devices. Are they solving any current problems? Or are they another case of technological solutions in search of a need to fulfill?

Mobile devices are a combination of hardware, operating system, networking, and software. We will examine the components of the technology and how they relate to the potential and need for hand-held computing. We will focus on hand-held devices (Personal Digital Assistants, cell phones, etc.) rather than laptop computers. Hardware Hardware for mobile technology hardware is young but maturing. Devices are getting smaller and more portable. The current trend is to combine capabilities of separate devices into one device and then identify the practical uses for the new hybrid devices. PDAs (Personal Digital Assistant) like a Palm Pilot or Handspring, originally only supported calendar/schedule and phonebook capabilities. More recent versions also are enabled with Global Positioning System (GPS), music, video games, paging, and even mobile (cellular) phone.

The main issue related to the hardware is the size. Manufacturers try to reduce the size of the devices so that more people will be willing to carry them around. However, if the devices are too small, they become difficult to read. Even more influential, the devices will remain primarily one-way systems (user receives data from device) until input methods as effective as keyboards are available.

Operating System: The operating system landscape for hand-held devices looks much like the PC landscape of the early 1980's. At that time multiple vendors developed solutions using proprietary operating systems. It took around 10 years for Microsoft Windows to emerge as the dominant standard. Currently, each type of mobile device has one or two custom operating systems on which the applications are deployed. As the device capabilities converge through hardware integration, the operating systems will grow to support the utilities of the other devices.

Because of their limited computational power and memory, most hand-held devices use embedded software - meaning that the application and the operating system are developed as a single unit. This means that the application is not easily transferred from one PDA hardware platform to another. The battle today for control of the operating system/application market is between:

1. Proprietary systems (faster, but with less portability) such as Palm and Symbian
2. Microsoft Windows-CE (more flexible, but slower and more expensive), and
3. Embedded Linux (flexible and inexpensive, but with less application development support).

Proprietary systems probably have around 65% of the market, Microsoft Windows CE has around 20%, and Linux has around 15% but its share is growing. Until there is a dominant operating system for mobile computing applications, the market will be stratified, and device applications will remain non-uniform across the range of devices. Networks: As with general computing networks mobile networks can be broken into local area networks and wide area networks. Wide area mobile networks consist of the same infrastructure being used for cell phones. Local area networks will require new hardware.

The current mobile phone network was developed for wide area voice communications. Voice communication uses a relatively low bandwidth circuit-switched network. This means that each phone conversation gets its own connection, but using very low data rates. Wide area data communication will require higher bandwidth, so the plan is to switch to packet-switched networks. This means that everybody will share higher bandwidth communications, and routing of information will be based on individual packet information (much as the internet functions today.)

The third generation (3G) cellular telephone network proposals consist of the transformation of the existing equipment into a packet-switched system. This change from current, 2G technology to 3G technologies is estimated to cost more than $300 billion dollar. To date, the detailed standards for 3G technologies have not been decided. Most markets are looking at easing into 3G by bridging the technologies. This intermediate step is referred to as "2.5G". Since current 2G technologies differ between countries around the world, some countries will find upgrading from 2G to 2.5G easier. 2.5G is supposed to provide an improvement in data rates from the current 9.6Kbps to 28.8Kpbs.

The goal of 3G is to provide not only higher bandwidth but also a worldwide converge of local and wide area mobile networks. 3G devices will intelligently detect and switch between a local area connection (when available) and the wide network when necessary. For example, if you are using your mobile device, and you receive an e-mail with an attachment that you want to print out, your mobile device will display the closest physical printer. With a click of a button your e-mail is sent to the printer and printed out. In your office your mobile device will have the intelligence to send and receive e-mails, pages, and phone calls through a local router. When traveling your device will send and receive these same data and phone calls through the cellular network. This technology is available today; however, cost, complexity, and availability are the primary issue.

Applications: The standard applications for each of the mobile devices are proven. This includes phone calls on mobile phones, short messaging through pagers, and calendar and phone book services for PDA's. Merging these applications into a single device is where the real challenge lies, particularly because of size issues.

The real power behind the hand-held approach has really been proven in the custom application area. The most visible examples are the "checking-in" and "checking-out" applications such as car rental and package delivery systems.

What we see happening: Most likely, over the next few years, mobile computing will remain a large niche market consisting of sub-niches (communications, calendaring, messaging). These popular applications will experience continued growth. However, because of the small or limited keyboard, small display screen, and slow communication speeds it is highly unlikely people will give up their notebook computers to work or web-surf from a mobile device full-time. Concepts such as web-surfing and product purchases from a cellular device will not materialize.

There will, however be a strong presence for short, time sensitive two-way event-driven messaging. Systems will be configured to notify a user of an event such as shipment of material. If a simple decision (yes/no, buy/sell) is needed, the user will be able to respond through the hand-held device. This is a limited but very reasonable use of the available technologies. Promises of the replacement of desktop and laptop computers by hand-held devices should be viewed skeptically.