Chances are, if you're living in the Eastern Hemisphere you're already familiar with i-Mode. But for most Westerners, i-Mode is something of an enigma. We've heard about it, but the truth is most of us really don't understand it (admit it). So what is i-Mode? Is it available to us in the western world? We'll get to all that in a moment. First, lets look to the Rising Sun and see where all this i-Mode stuff came from.

What is i-Mode and how'd it all start?

In 1999, NTT DoCoMo, Japan's leading cellular phone operator, launched a service called i-Mode. i-Mode (which stands for information-mode) is a mobile phone service which offers continuous Internet access. i-Mode is similar to WAP (WAP is another technology which has a scope of offering Internet access worldwide).

The reason DoCoMo decided to go with i-Mode instead of waiting for WAP is simple. The Japanese were ready to access the Internet through their mobile phones. They didn't want to have to wait for WAP to provide them with wireless data services they needed.

Consider that last year, NTT DoCoMo had 21 million subscribers and products that were preparing for the coming of W-CDMA (a technology that allows for the high-speed transmission of video and large-volume data). The Japanese - who make up the world's second-largest mobile phone market - were ready to access the Internet through their mobile phones. Thus, DoCoMo created i-Mode, along with a network of partners who offered specially formatted websites to fit into the small screen on the mobile handset.

NTT DoCoMo's decision to forego WAP for i-Mode was a completely practical solution. And with 10 million new subscriptions predicted for the service within the next three years, the decision was obviously the right one.

What does an i-Mode enabled phone look like?

An i-Mode enabled cellular phone is similar to in appearance to most cellular phone models. One feature in particular is a four-point command navigation button at the center of the phone. This allows the user to control the pointer on the display, as well as connect to the i-Mode service by pressing a single button.

There are several companies that manufacture i-Mode cellular phones, including Panasonic, Nokia, Ericsson, and Sony (these models are only available within the Asia Pacific - see Figure 1a). However, NTT DoCoMo's models are the most popular within the industry.

Figure 1a. Nokia's i-Mode enabled phone

                  

How does the i-Mode network service work?

The i-Mode service uses an additional packet communication network that is built onto DoCoMo's main network. This packet data transmission technology allows for constant connectivity. Thus, users are not charged for how long they are online, since this time is unlimited. Rather, users are charged only for how much information they retrieve.

With that said, there are essentially four main components that are required for the i-Mode service. They are as follows:

• A cellular phone capable of voice and packet communication and with a browser installed
  
• A packet network
  
• An i-mode server
  
• Information providers

Unfortunately, the i-Mode service is currently available in Japan and Hong Kong only. However, there are plans in the works to bring i-Mode to parts of Europe in the near future. It is unknown at the moment if i-Mode will make it to the United States.

How does an i-Mode-enabled phone connect to a wireless network?

Typically, networks utilize two types of computers - servers and clients. Servers are the computers that hold information. Clients are the computers that we view the information from.

The way the Internet works is that servers hold our web pages. We then view these web pages from our PCs (the clients). In the case of the i-Mode Internet, an Internet server contains the i-Mode web pages. But now, instead of viewing the pages from a PC, we are using a cellular i-Mode phone. These phones are now the clients.

There are two other factors involved in connecting a to a wireless network. In order to connect a cellular network to a server, a gateway must exist. Also, the web site must be in an i-Mode format.

What is a gateway?

A gateway translates wireless requests from a mobile phone to the server. It also sends information from a gateway back to the mobile phone. NTT DoCoMo provides a gateway to their users; however, this is only available to those in Japan.

There are other gateways on the market that allow users outside of Japan to build new mobile Internet services based on cHTML. One of the new gateways to hit the market is the m-WorldGate. This is the world's first commercially available cHTML gateway. m-WorldGate was developed by Logica.

What is an i-Mode enabled site?

Web pages today are often written in HTML (Hypertext Markup Language), which is too complex for mobile phones because of their slower connection speeds. An i-Mode enabled web sites utilizes pages that are written in cHTML (Compact Hypertext Markup Language), which is a subset of HTML designed for devices with slower connection speeds.

Today, the i-Mode service boasts 500+ i-Mode enabled websites linked to a portal page, as well as 12,000+ "unofficial" web pages created by private individuals.
What is cHTML like?

cHTML is extremely similar to HTML - in fact, it is HTML. The only difference is that some of the more resource intensive areas of the code (such as tables and frames) have been taken out. Mobile devices have a slower connectivity speed. Thus, by eliminating some of the more involved portions of the code, cHTML allows i-Mode web pages to download more quickly to mobile devices.

The World Wide Web Consortium (www.w3.org) contains a complete listing of the cHTML tags available to developers. Also, you can visit the NTT DoCoMo site at www.nttdocomo/ser2.htm for an outline of cHTML tags available to developers.

What do i-Mode enabled web sites look like?

Most i-Mode phones today utilize a micro-browser. These usually have a title bar with icons at the top of an LCD screen. These icons then allow users to access various services such as weather forecasts, transportation schedules, data searches, and news updates. Below this title bar is a text screen that displays text messages and data (Figure 1b).

One micro-browser in particular is Compact NetFront, developed by the Japanese company Access. Compact NetFront is used as the micro-HTML browser for about 75% of all i-Mode enabled devices. Information on Access's Compact NetFront can be found at www.access.co.jp/english/product/proline/c_nf.htm.

Figure 1b. Compact NetFront Micro-browser

How do I develop an i-Mode application?

The criteria for creating an i-Mode application or an i-Mode web page are essentially the same as creating web apps and web pages with HTML. You must develop in the cHTML language, and then load the page to an Internet web server utilizing FTP or some other transfer method.

Currently, the cHTML language does not support scripting language (this being a major obstacle for developers). However, NTT DoCoMo and Sun Microsystems have announced an alliance recently. There are plans to incorporate Java, Jini, and Java Card technologies into i-Mode cellular phones. The first wave of these phones is expected to hit the market around the end of 2000.

Where can I find out more information about i-Mode?

Finding information about i-Mode can be a challenge here in the western world (a lot of the information isn't available in English). Do check out NTT DoCoMo's site at www.nttdocomo.com for great information about the latest developments with i-Mode and the company that is making it possible. Also, you can look to our site for the most current information and news regarding i-Mode and its place in the wireless industry as a whole.