Near Field Comunications

Transcription

1 Near Field Comunications Bridging the Physical and Virtual Worlds This is going to get interesting! Siamak Ashrafi

2 NFC Definition Near field communication, or NFC, is a set of short-range wireless technologies, typically requiring a distance of 4 cm or less. NFC operates at MHz and at rates ranging from 106 kbit/s to 848 kbit/s Globally available and unlicensed! NFC always involves an initiator and a target; the initiator actively generates an RF field that can power a passive target (tags, stickers, key fobs, or cards) that do not require batteries. NFC peer-to-peer communication is also possible, where both devices are powered. NFC device work on a close range that I call near-to-near

3 Communication Supported data rates: 106, 212, 424 or 848 kbit/s Passive Communication Mode: The Initiator device provides a carrier field and the target device answers by modulating the existing field. In this mode, the Target device may draw its operating power from the Initiator-provided electromagnetic field, thus making the Target device a transponder. Active Communication Mode: Both Initiator and Target device communicate by alternately generating their own fields. A device deactivates its RF field while it is waiting for data. In this mode, both devices typically have power supplies.

4 Relations Compared to other wireless technologies such as Bluetooth or WiFi, NFC provides much lower bandwidth and range, but enables low-cost, un-powered targets and does not require discovery or pairing. Interactions can be initiated with just a tap. RFID NFC is compatible with existing passive RFID (13.56 MHz ISO/IEC ) infrastructures. Unlike RFID, NFS is read/writer! Bluetooth Bluetooth pairing: in the future, pairing of Bluetooth 2.1 devices with NFC support will be as easy as bringing them close together and accepting the pairing. The process of activating Bluetooth on both sides, searching, waiting, pairing and authorization will be replaced by simply bringing the mobile phones close to each other. NFS does not need a GUI!

5 Patents & Standards Patents: Sony & Phillips building on their RFID work. A patent licensing program for NFC is currently under development by Via Licensing Corporation, an independent subsidiary of Dolby Laboratories. Standards: NFC is an open platform technology standardized in ECMA-340 and ISO/IEC These standards specify the modulation schemes, coding, transfer speeds and frame format of the RF interface of NFC devices, as well as initialization schemes and conditions required for data collision-control during initialization for both passive and active NFC modes. Furthermore, they also define the transport protocol, including protocol activation and data-exchange methods.

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7 Market It is BIG

8 NFC & Android A team from Stanford's MobiSocial lab has developed two applications for the Google Nexus S that use NFC's peer-topeer capability: A phone-to-phone file transfer service and a collaborative whiteboard. The first NFC Android applications have appeared in Google's Android Market. One, the U.S.-based EnableTable, is an app designed for American restaurant owners who want to offer discounts to their regular customers. The second, a Japanese app called Taglet, lets you register NFC devices with its service, which, when read, will retrieve stored data like a website address or contact information.

9 Keys, ID, Credit Cards & Phone Everything is password protected

10 Square and NFC Most of the attention focuses on NFC (Near Field Communications), which is being built into forthcoming version of mobile devices and will obviate the need for solutions such as Square. Rabois dismisses all such talk and argues that the consumers as such are still going to have to carry debit cards, driver licenses and other such cards, which means the wallet as we know it isn t going to go away. As long as there are cards with magnetic strips, readers such as Square and the back-end services that support them are going to be in demand.

11 NFC & Healthcare

12 NFC & Healthcare

13 Working with Data on NFC Tags Data on NFC tags are encoded in raw bytes, so you must convert the bytes to something human readable if you are presenting the data to the user. When writing to NFC tags, you must write them in bytes as well. Android provides APIs to help write messages that conform to the NDEF standard, which was developed by the NFC Forum to standardized data on tags. Using this standard ensures that your data will be supported by all Android NFC devices if you are writing to tags.

14 Tag Dispatch System Always try to use: Android Application Records

15 API Overview

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19 Reading an NFC Tag When a device comes in proximity to an NFC tag, the appropriate intent is started on the device, notifying interested applications that a NFC tag was scanned. By previously declaring the appropriate intent filter in your AndroidManifest.xml file or using foreground dispatching, your application can request to handle the intent.

20 Writing to an NFC Tag Writing to an NFC tag involves constructing your NDEF message in bytes and using the appropriate tag technology for the tag that you are writing to.

21 NFCDemo TagViewer an Activity that handles a broadcast of a new tag that the device just discovered, parses it, and displays its record contents in alistactivity NdefMessageParser parses the record type of records within the NDEF message. ParsedNdefRecord an interface implemented by all parsed NdefRecord types. SmartPoster a representation of an NFC Forum Smart Poster Record Type. TextRecord a representation of an NFC Forum Text Record Type. UriRecord a representation of an NFC Forum Uri Record Type. FakeTagsActivity A activity that launches tags as if they had been scanned. This is useful if you don't have access to NFC enabled device or tag. MockNdefMessages this class provides a list of fake NFC Ndef format Tags.

22 Peer-to-Peer Data Exchange Support for simple peer-to-peer data exchange is supported by the foreground push feature The Activity that is pushing the data must be in the foreground You must encapsulate the data that you are sending in an NdefMessage object The NFC device that is receiving the pushed data (the scanned device) must support the com.android.npp NDEF push protocol, which is optional for Android devices.

23 Google Beam Demo code:

24 Card Emulation Citi MasterCard or the Google Prepaid Card

25 NFC Summary Q&A Sample Code, Documentation