近場通訊 NFC, Over-the-air programming - 維基百科 Wikipedia

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近場通訊

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近場通訊（英語：Near Field Communication，NFC），又稱近距離無綫通訊，是一種短距離的高頻無綫通訊技術，允許電子設備之間進行非接觸式點對點數據傳輸，在十公分（3.9英吋）內交換數據。

這個技術由免接觸式射頻識別（RFID）演變而來，由飛利浦半導體（現恩智浦半導體）、諾基亞和索尼共同研製開發，其基礎是RFID及互連技術。近場通訊是一種短距高頻的無綫電技術，在13.56MHz頻率運行於20公分距離內^[1]。其傳輸速度有106 Kbit/秒、212 Kbit/秒或者424 Kbit/秒三種。目前近場通訊已通過成為ISO/IEC IS 18092國際標準、EMCA-340標準與ETSI TS 102 190標準。NFC採用主動和被動兩種讀取模式。

目錄

  [隱藏] 

• 1 NFC工作模式
• 2 與藍牙的比較
• 3 可利用NFC通訊的作業系統與軟件
  • 3.1 Android
  • 3.2 Windows Phone 8
  • 3.3 Windows 8
  • 3.4 跨作業系統通訊
• 4 商務應用
  • 4.1 台灣
  • 4.2 香港
• 5 內置NFC的裝置
• 6 注釋
• 7 外部連結

NFC工作模式

卡模式（Card emulation）：這個模式其實就是相當於一張採用RFID技術的IC卡。^{[來源請求]}可以替代現在大量的IC卡（包括信用卡）場合商場刷卡、悠遊卡、門禁管制，車票，門票等等。此種方式下，有一個極大的優點，那就是卡片透過非接觸讀卡器的 RF 域來供電，即便是寄主裝置（如手機）沒電也可以工作。

點對點模式（P2P mode）：這個模式和紅外線差不多，可用於數據交換，只是傳輸距離較短，傳輸建立速度較快，傳輸速度也快些，功耗低（藍芽也類似）。將兩個具備NFC功能的裝置連結，能實作數據點對點傳輸，如下載音樂、交換圖片或者同步裝置位址薄。因此透過NFC，多個裝置如數位相機、PDA、電腦和手機之間都可以交換資料或者服務。

讀卡器模式(Reader/writer mode)：作為非接觸讀卡器使用，比如從海報或者展覽訊息電子標籤上讀取相關訊息。

與藍牙的比較

	NFC	Bluetooth	Bluetooth Low Energy
RFID 相容	ISO 18000-3	active	active
標準化機構	ISO/IEC	Bluetooth SIG	Bluetooth SIG
網絡標準	ISO 13157 etc.	IEEE 802.15.1	IEEE 802.15.1
網絡類型	Point-to-point	WPAN	WPAN
加密	not with RFID	available	available
範圍	< 0.2 m	~10 m (class 2)	~1 m (class 3)
頻率	13.56 MHz	2.4-2.5 GHz	2.4-2.5 GHz
Bit rate	424 kbit/s	2.1 Mbit/s	~1.0 Mbit/s
設定程式	< 0.1 s	< 6 s	< 1 s
功耗	< 15mA (read)	varies with class	< 15 mA (xmit)

NFC和藍牙都是短程通訊技術，而且都被整合到手提電話。但NFC不需要複雜的設定程式。NFC也可以簡化藍芽連線。

NFC略勝藍牙的地方在於設定程式較短，但無法達到低功率藍芽（Bluetooth Low Energy）的傳輸速率。在兩台NFC裝置相互連線的裝置識別過程中，使用NFC來替代人工設定會使建立連線的速度大大加快：少於十分之一秒。NFC的最大數據傳輸量 424 kbit/s 遠小於 Bluetooth V2.1 (2.1 Mbit/s)。雖然NFC在傳輸速度與距離比不上藍牙 (小於 20 cm)，但相應可以減少不必要的干擾。這讓NFC特別適用於裝置密集而傳輸變得困難的時候。

相對於藍芽，NFC相容於現有的被動 RFID (13.56 MHz ISO/IEC 18000-3) 設施。NFC的能量需求更低，與藍芽 V4.0低能協定類似。當NFC在一台無動力的裝置(比如一台關機的手機，非接觸式智能信用卡，或是智能海報)上工作時，NFC的能量消耗會要大於低能藍芽 V4.0。

對於手提電話或是行動消費性電子產品來說，NFC的使用比較方便。NFC的短距離通訊特性正是其優點，由於耗電量低、一次只和一台機器連結，擁有較高的保密性與安全性，NFC有利於信用卡交易時避免被盜用。NFC的標的並非是取代藍芽等其他無綫技術，而是在不同的場合、不同的領域起到相互補充的作用。

可利用NFC通訊的作業系統與軟件

Android

• Android Beam
  • 由Google及OHA製定，利用內建NFC晶片、並使用Android作業系統的裝置間互相通訊、傳輸網址、Google地圖資訊、聯絡人資訊(vCrad)或圖片。此功能限定Android 4.0以上的裝置才可使用。^[2]

• S Beam
  • 由Samsung製作，目前僅內建於部分Samsung生產的Android裝置上，當兩隻內建S Beam的手機利用NFC通訊後，便會開啟Wi-Fi Direct功能進行高速傳輸，甚至可傳輸大容量的音樂、影片檔案^[3]。與其功能類似的軟件如Majed Alhajry製作的Super Beam^[4]。

Windows Phone 8

• 輕觸+傳送
  • 適用於內建NFC功能的Windows Phone 8裝置，可利用NFC與藍牙功能傳輸網址、圖片、影片或聯絡人數據。^[5]

Windows 8

• 輕觸並傳送
  • 部分發售的Windows 8手提電腦內建NFC功能，使其能與其他Windows 8手提電腦、流動裝置進行通訊。^[6]

跨作業系統通訊

• 使用Android作業系統的裝置與Windows Phone 8及Windows 8作業系統亦可利用NFC傳輸資訊。^[7][8]

商務應用

台灣

• Hami智能錢包
  • 由國泰世華、中華電信與萬事達卡合作，結合PayPass技術、NFC、OTA、高安全性的SWP-SIM卡與Hami智能錢包的密碼保護，提供消費者在擁有PayPass付款機制的商店進行消費，付款單筆上限為3000元台幣。目前為試辦期，僅國泰世華與中華電信員工申請使用，預計2013年下半年度正式發行。^[9]

• NFC手機一卡通
  • 由高雄捷運與中華電信合作，將「一卡通」服務導入手機NFC應用，成為全國首張NFC手機交通票證，不但可使用NFC手機搭乘捷運，也能透過手機隨時查詢票卡餘額或交易紀錄，卡片資訊亦能透過空中下載至手機SIM卡，即使更換手機也能繼續使用，目前先於中華電信及高雄捷運進行員工服務測試，預計2013年年底正式推出。^[10]

香港

內置NFC的裝置

現時大部份有內置NFC的裝置皆以手提電話為主，2006年諾基亞推出第一部內置NFC的手機，其後開始陸續有不少手機型號推出有關功能的產品。 目前市場上內建NFC的手機還比較少，在售型號中有HTC的One系列( One Mini除外)三星的Galaxy S3,Note2,諾基亞的Lumia720,820,920,925,1020,1520，索尼的Xperia™Z1,Z,ZR,Z Ultra可以支援NFC。

注釋

1. ^ Ortiz 2008.
2. ^ 傳輸畫面內容. Google.
3. ^ 用 Wi-Fi Direct 無限串連你的裝置：Samsung S Beam. 鄭翔文. [February, 27, 2013].
4. ^ SuperBeam - WiFi Direct Share. Google Play. [March, 30, 2013].
5. ^ 點選以分享相片、網站及其他內容. Microsoft Windows操作說明(台灣).
6. ^ 輕觸即可和身旁的人一起分享. Microsoft Windows.
7. ^ NFC sharing between Android and Windows Phone 8. Alex Dobie. [October, 29, 2012].
8. ^ NFC Windows 8 to Android Demo. 365CloudTech. [November, 23, 2012].
9. ^ 開放中華電與國泰世華員工申請試用，NFC 手機信用卡時代就快來了. Mengkuei Hsu. [May, 10, 2013].
10. ^ 中華電攜手高捷，「一機在手，港都Smart遊」手機交通票證卡試辦計畫啟用，最快年底上路.

外部連結

• ISO/IEC 18092:2004 標準
• NFC TIMES
• Open source NFC Eclipse plugin

• 本頁面最後修訂於2013年11月25日 (星期一) 21:16。

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http://en.wikipedia.org/wiki/Over-the-air_programming

Over-the-air programming

From Wikipedia, the free encyclopedia

Over-the-air programming (OTA) refers to various methods of distributing new software updates, configuration settings, and evenupdating encryption keys to devices like cellphones, set-top boxes or secure voice communication equipment (encrypted 2-way radios). One important feature of OTA is that one central location can send an Update to all the Users; who are unable to refuse, defeat, or alter that Update, and it applies immediately to everyone on the Channel. A User could "refuse" OTA but the "Channel Manager" could also kick them off the Channel (automatically).

In the context of the mobile content world these include over-the-air service provisioning (OTASP), over-the-air provisioning (OTAP) or over-the-air parameter administration (OTAPA), or provisioning handsets with the necessary settings with which to access services such as WAP or MMS. On modern mobile devices such as smartphones, an over-the-air update may refer simply to a software update that is distributed over Wi-Fi or mobile broadband using a function built into the operating system, with the "over-the-air" aspect referring to its use of wireless internet instead of requiring the user to connect the device to a computer via USB to perform the update.

As mobile phones accumulate new applications and become more advanced, OTA configuration has become increasingly important as new updates and services come on stream. OTA via SMS optimises the configuration data updates in SIM cards and handsets and enables the distribution of new software updates to mobile phones or provisioning handsets with the necessary settings with which to access services such as WAP or MMS. OTA messaging provides remote control of mobile phones for service and subscription activation, personalization and programming of a new service for mobile operators and telco third parties.^[1]

Various standardization bodies were established to help develop, oversee, and manage OTA. One of them is the Open Mobile Alliance(OMA).

More recently, with the new concepts of Wireless Sensor Networks and the Internet of Things, where the networks consist of hundreds or thousands of nodes, OTA is taken to a new direction: for the first time OTA is applied using unlicensed frequency bands (2.4 GHz, 868 MHz, 900 MHz) and with low consumption and low data rate transmission using protocols such as 802.15.4 and ZigBee.^[2]

Motes are often located in places that are either remote or difficult to access. As an example, Libelium has implemented a smart and easy-to-use OTA programming system for ZigBee WSN devices. This system enables firmware upgrades without the need of physical access, saving time and money if the nodes must be re-programmed.^[3]

Contents

  [hide] 

• 1 Mechanism
• 2 Methods
• 3 Other Verizon methods
• 4 OTA standards
• 5 Similarities
• 6 References

Mechanism

The OTA mechanism requires the existing software and hardware of the target device to support the feature, namely the receipt and installation of new software received via the wireless network from the provider.

New software is transferred to the phone, installed, and put into use. It is often necessary to turn the phone off and back on for the new programming to take effect, though many phones will automatically perform this action.

Methods

Depending on implementation, OTA software delivery can be initiated upon action, such as a call to the provider's customer support system or other dialable service, or can be performed automatically. Typically it is done via the former method to avoid service disruption at an inconvenient time, but this requires subscribers to manually call the provider. Often, a carrier will send a broadcast SMS text message to all subscribers (or those using a particular model of phone) asking them to dial a service number to receive a software update.

Verizon Wireless in the U.S. provides a number of OTA functions to its subscribers via the *228 service code. Option 1 updates phone configuration, option 2 updates the PRL. Similarly Voitel Wireless that uses Verizon network uses *22890 service code to program Verizon based Voitel wireless phones. Interop Technologies provides a number of nationwide wireless operators in the US with an SS7 Based Over-the-Air device management solution.^[4] This solution allows operators to manage wireless device functionality including renumbering handsets, updating phone settings, applications and subscriber data and adjusting PRL to manage cost structures.

To provision parameters in a mobile device OTA, the device needs to have a provisioning client capable of receiving, processing and setting the parameters. For example, a Device Management client in a device may be capable of receiving and provisioning applications, or connectivity parameters.

In general, the term OTA implies the use of wireless mechanisms to send provisioning data or update packages for firmware or software updates to a mobile device — this is so that the user does not have to go to a store or a service center to have applications provisioned, parameters changed or firmware or software updated. Non-OTA options for a user are a) to go to a store and seek help b) use a PC and a cable to connect to the device and change settings on a device, add software to device, etc.

Other Verizon methods

*228 option 1

-Programs the MDN, MIN and Home SID into the phone, downloads the latest PRL, and sets the lock code to the last 4 digits of the MDN.

*228 option 2,

-Only downloads the current PRL.

*22890,

-Automatically performs option 1 without having to press 1.

*22891

-Automatically performs option 2 without having to press 2.

*22899

-Automatically performs option 1, plus applies changes specific to data cards. Note: Do not perform *22899 on any device that is not a data card.

*22888

-Unassisted OTA for Prepaid phones

OTA standards

There are a number of standards that describe OTA functions. One of the first was the GSM 03.48 series. The ZigBee suite of standards includes the ZigBee Over-the-Air Upgrading Cluster which is part of the ZigBee Smart Energy Profile and provides an interoperable (vendor-independent) way of updating device firmware.

Similarities

OTA is similar to firmware distribution methods used by other mass-produced consumer electronics, such as cable modems, which useTFTP as a way to remotely receive new programming, thus reducing the amount of time spent by both the owner and the user of the device on maintenance.

Over-the-air provisioning (OTAP) is also available in wireless environments (though it is disabled by default for security reasons). It allows an access point(AP) to discover the IP address of its controller. When enabled, the controller tells the other APs to include additional information in the Radio Resource Management Packets (RRM) that would assist a new access point in learning of the controller. It is sent in plain text however which would make it vulnerable to sniffing and why it is disabled by default.

References

1. Jump up^ "Mobile Phones — Mobile Explorer". Microsoft. 2001. Archived from the original on 11 August 2001. Retrieved 19 April 2011.
2. Jump up^ Gascón, David; Alberto Bielsa, Félix Genicio, Marcos Yarza (9 May 2011). "Over the Air Programming with 802.15.4 and ZigBee - OTA".Libelium. Libelium. Retrieved 28 May 2012.
3. Jump up^ "Libelium.com 50 Sensor applications for a Smarter World. Get Inspired!". Libelium.com. Libelium.com. 2 May 2012. Retrieved 28 May 2012.
4. Jump up^ "Alaska DigiTel Buys OTA Programming Solution from Interop Technologies". Tmcnet.com. 2008-04-01. Retrieved 2012-02-02.

• This page was last modified on 22 November 2013 at 12:39.

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