Service Provisioning through Real World Objects

Introduction

In recent years, tagging technologies, such as Near Field Communication (hereafter NFC) (ECMA 2006), Radio Frequency Identification (RFID) (EPC Global 2006) and 2-dimensional bar codes (Adams, 2007) have received a great deal of attention because of their ability to associate digital information with arbitrary objects. In principle everything can be cheaply tagged, from coffee mugs to advertisement posters, and applications can be invoked on the basis of the information that is gathered from the tags on the object.

Japan has seen initial commercial deployments of these technologies. There 2D tagging of advertisements is quite common as shown by the banner in Figure 1. By taking a picture of the tag, a mobile user would immediately gain access to an airline Web page and there buy tickets to fly anywhere in the world. NFC tagging in combination with mobile phones is also widely used in Japan through iMode-FeliCa (Yoshinaga, 2003). Tagging technologies are also becoming increasingly common in Europe and the US. For example, the German railroad operator Deutsche Bahn uses 2D bar codes to store train tickets directly on the phone (Deutsche Bahn, 2007). Furthermore, tagging is also widely used in B2B solutions to monitor stock inventory, logistics and transport to track moving goods (Meloan, 2003). By tagging containers as well as single products, companies can easily manage their inventory, keep track of the goods that have been received and monitor their position during the delivery process (IDTechEx, 2007)(Tohamy, 2005).

Figure 1.

A banner with a 2D bar code in Tokyo

Whereas tagging is entering the computer science main stream, it also provides new challenges. The first one is that tags, by and large, do not have any processing abilities, rather they always passively return the same value. Even when active tags exists, as in the case of NFC and RFID, their cost is approximately 100 times higher than the corresponding passive tags making the broad use of active tags very costly. The second challenge is that tags have very limited memory storage, which ranges from a few bytes to a few Kbytes. The third challenge is that the range of the “network” to read a tag is also very limited, spanning from a few centimeters in the case of NFC tags, to a few meters in the case of RFID tags. The fourth challenge, which is important for this chapter, is that tags break the traditional structure of SOA-based applications which assumes that services are always available and discoverable through a registry.

In this chapter, we attempt to tackle the challenge of providing a general Web service infrastructure to support the user to interact with advertisement posters (UsingRFID.com, 2007). Through the chapter, we will use the movie poster displayed in Figure 2 as our main example. The goal of the poster is to advertise movies that are playing in town. But the poster achieves more than that, the little squares on the side of the poster specify additional information such as: the movie theaters where the movies are played (on the upper left side), the show times (on the upper right), and the number of tickets that the user may be able to buy (on the bottom left), public transport tickets to go to the theater (on the bottom right).). Crucially, each one of the little boxes is associated with an NFC tag that can be read with any mobile phone with an appropriate reader. A mobile user swiping her phone on the tags should be able to purchase a ticket to a showing of the desired movie, and a public transport ticket to go to the movie. Ultimately, the poster becomes the interface of a ticket selling services.