Near field communication
Introduction
According to Wikipedia (4/2015), Near field communication (NFC) is somewhat similar to Bluetooth, but works at much smaller distances (< 10 to 20 cm). NFC is much slower than Bluetooth, but requires less energy . NFC is compatible with existing passive RFID (13.56 MHz ISO/IEC 18000-3) infrastructures. E.g. in order to play with this technology, you should have a cellphone, then download an end-user app for writing something on a cheap RFID tag.
NFC has been invented in 2002 by NXP Semiconductors and Sony and in 2010, Google launched the Nexus S, the first Android NFC phone. In 2011, Google launches Google wallet. Most 2014/15 cellphones include NFC support, but Apple only for iPhone 6. The most typical use case are contactless payment systems.
There are two main devices which translate to possible modes of operation:
- Active chips. These can work in either target (see below), initiator (read or write) or peer to peer mode.
- Passive target chips, also called "tags" (allows to transfer data to an initiator).
Active NFC devices can read data from tags. Some tags are rewritable. Some are crypted. There are standards, but target chips also can be custom encoded.
Uses
Some general use cases ares:
- Wireless payment
- Bootstrapping other connections
- Social networking
- Intenty and keys
- Gaming, (e.g. virtual treasure hunts or the crytped Amiibos)
In education, NFC tags can be used in a similar way as QR tags.
Tools
- End user software for Android devices
... there are many more
- End user computer / Android phone
- NFC Developer allows to create on the computer. The result is then put into QR tag that you can scan with the app. However, there is a hardware add-on for reading RFID/NFC chips (icarte)
- End user software for IOS / Apple
- The iPhone 6 has a kind of NFC chip, but it seems that its use is locked (Stackoverflow, sep 2014)
- Indexes
NFC tags
There exist many brands. Comsumer chips can be bought in electronic shops and online retailers.
- Which NFC Chip ? (comparison of RapidNFC products)
If you plan to store longer URLs or procedures, make sure that it has enough memory, at least 500 bytes, more is better.
WhizTags
Whiztags sells s everal models.
- The Topaz 512 seems to be a popular one (at the time of writing). It includes 450 bytes of writeable memory and it sticks quite well to most surfaces.
NXP / NTAG
NXP is a semiconductor manufacturer and was co-inventor of NFC technology. They also sell end-user tags, e.g.
- The NTAG 216 has a memory of 888 Bytes
Samsung TecTiles
TecTiles are Samsung's stickers with an embedded NFC chip and are sold by packs of five. A free TecTile app allow to "program" these with series of predefined tags that will interact with your Samsung phone, its browsers, etc. See the kinds of tags you can make in the FAQ. The TecTiles application is not meant to used with other other Android phones. I.e. if you write a tag with TecTiles, it will launch a TecTiles application on your phone that in turn will launch stuff. On other phones, you might see links from which you can choose.
Links
- Introductions
- Technology Tutorials
- NFC Near Field Communication Tutorial, by Ian Poole, radio-electronics.com. Very detailed, technical.
- End user tutorials
- How to encode NFC tags (tutorial for the NFX tag writer app).
- Programming
- Get started with NFC Android, May 2012.
- In education
- How can I use NFC to engage my students? JISC Inform,
- How to use Near Field Communication to engage your foreign students by Simon Wardman, 5 September 2013, Jisc blog.