Object hyperlinking

Definition

There is no established term to describe the subject of this article. Until one emerges it may, for the sake of brevity, be referred to as object hyperlinking. The purpose of what is described below is to extend the internet to objects and locations in the real world; to create an internet of things. The current internet does not extend beyond the electronic world. Object hyperlinking would extend the internet to the real world by attaching tags with URLs to tangible objects or locations. These tags could be read by a wireless connected mobile device and information about objects and locations retrieved and displayed.

System components

An object hyperlinking system has six main components -

1. A physical or virtual tag to identify objects and locations. Some tagging systems are described below. To allow the smaller physical tags to be located they must be embedded in visual markers. For example, the Yellow Arrow system [see below] prints SMS tags on large adhesive yellow arrows, which can then be stuck on buildings etc.
2. A means of reading physical tags, or locating virtual tags.
3. A mobile device such as a mobile telephone, a PDA or a portable computer.
4. A digital wide area wireless network, such as the existing 2G and 3G networks, for communication between the portable device and the server containing the information linked to the tagged object.
5. Information on each linked object. This information could be in existing WWW pages, existing databases of price information etc, or have been specially created.
6. A display to view the information on the linked object. At the present time this is most likely to be the screen of a mobile telephone. It would therefore be necessary to reformat some data, such as existing web pages designed for display on PC monitors, to allow its display on portable viewers.

Tags and tag readings systems

There are a number of different competing tagging systems.

RFID tags – a Radio Frequency Identification Device is a small transponder which can be read at short range by a transceiver [reader]. A RFID reader can be added to an existing mobile telephone as a shell. Nokia produce such a shell for their 3220 mobile telephone. At the moment few mobiles have RFID capability but this may change, since such RFID enabled mobiles may be used for cashless payments and other purposes. From 2005 travelers in the city of Hanau, near Frankfurt, Germany will be able to pay for bus tickets by passing their Nokia phones over a smart-card reader installed on the buses. Other applications for RFID enabled mobiles include swapping electronic business cards between phones, and using a mobile to check in at an airport or hotel. Two RFID enabled devices may also be used to enable peer to peer transfer of data such as music, images or for synchronizing address books. Since RFID tags are very small they must be embedded in a more visible marker to allow them to be located and read.

Graphical tags - a graphical tag consists of an image on a marker which can be read by a mobile telephone camera. There are a number of competing systems, including Semacodes, QR codes, Shotcodes and barcodes. The design of such coding schemes needs to be rich enough to include lots of information and robust enough for the tag to be readable, even when partly obscured or damaged [tags might be on the outside of buildings and exposed to wear and the weather]. Graphical tags have a number of advantages. They are easy to understand and cheap to produce. They can be printed on almost anything, including t-shirts. They can be read by mobile telephone cameras, and these are becoming ubiquitous.

SMS tags – a SMS tag consists of a short alphanumerical code which can be keyed into a mobile. The Short Message Service is then used to send the code and return a message. An example of this form of tagging is the Yellow Arrow scheme. The Christian Science Monitor and the Washington Post have articles about Yellow Arrows.

Virtual tags – in a virtual tagging system there is no physical tag at a location. Instead a URL is associated with a set of geographical coordinates. When a GPRS equipped mobile phone enters a particular area the phone can be used to retrieve all URLs associated with that area. The area can be set as a few metres or a much wider area. At the moment few mobiles are GPRS enabled and GPRS is not accurate in urban areas. The accuracy of GPRS may improve when the European Union Galileo positioning system is operational in 2008.

Applications for object hyperlinking

The object hyperlinking systems described above will make it possible to link comprehensive and editable information to any object or location. How this capability will be used remains to be seen. Some uses are starting to emerge.

• The publishers of the Lonely Planet guide books are issuing yellow arrows with one of their guide books and encouraging travellers to leave tags to stories and comments wherever they go.
• Siemens see their virtual tagging system being used to tag tourist sites, and also leave messages for friends.
• Siemens also suggest that virtual tags could be used to link advertisements with locations.
• Nokia have demonstrated that when a 3220 phone with the RFID shell attached is tapped against an RFID-enabled advertisement, a URL can be read and information about the advertised product or service returned to the phone.
• Japanese consumers are able to read product barcodes with their mobiles and download comparative prices from Amazon.
• The Mobile Weblog and Eclectica have promoted the idea of a Mobile Wikipedia.