How does NFC work…
Let’s starth with the basics. From a user’s perspective, NFC consists of two components; a Reader and a Tag. Bring them close to one another and presto!
Tags contain pieces of information, for example, as simple as a memo, like “Hi, my name is John”. They can also contain complex command structures, like “download Angry Birds, install it, and send a message to John that I am playing Angry Birds”.
Initially, tags are blank so one must write to the tag to put information in it; in other words, program the tag. So, a tag, can be written to, and read from. This can happen repeatedly. In fact, you can control whether it happens at all.
On the other hand, a Reader, does exactly that… It reads information found in the tag; In the simplest case, it reads data and takes action based on the app the tag is associated with; For example, popping up a notification, “Hi, my name is John”, or installing Angry Birds™ and then it sends a message. Of course, the Reader is usually, though not always, aWriter.
NFC chips in a mobile phone can act both as a tag and a reader/writer. Pretty cool!
NFC is unique when compared to other mobile communications technologies (e.g., Wifi, Bluetooth, 3G, 4G) in that it supports communication with passive (non-powered) devices. That means that only one device has to be powered, usually the Reader/Writer. That means that if your mobile phone loses power and you still want to make a payment with the secure info on your phone, you can still do that. You can read more on Security here.
NFC defines three communication modes:
- Tag Read/Write : This is where you can communicate with Tags, Labels, Posters, Cards etc… This is contactless infrastructure containing the all important pieces of information.
- Peer-to-Peer Communication: This is where you connect devices to one another in physical proximity, neither of which is connected to anything else. They exchange information with one another. For example, two mobile phones exchanging business cards.
- Secure Card Emulation: This incorporates the use of a Secure Element, which allows your mobile phone to act like a payment, transport or physical access card, just like a credit card, a bus pass, or a security badge to unlock a secure area (Read more on the Secure Element).