物联网（Internet of things），简称IoT，这是个目前很火的一个词，对于从事IT行业的人来说，更是耳熟能详。但是对于不在这个行业的朋友来说，可能会处在知其名而不能会其意状态，有些朋友还可能十分自信的理解为搞物流，还有一些朋友处在一脸懵逼的状态。秉着分享好东西的精神，本文将对IoT的定义、模型、应用做简要介绍。

在介绍之前，先参考下IDC对IoT的发展预测：

 IDC now predicts that by 2020, the IoTnetwork will consist of more than 29 billion connected devices.And experts are estimating that the data from these devices will yield insights that drive economic value of more than $11 trillion by 2025. Some experts still feelthese numbers are too conservative.

很显然，前（钱）途无量！

 到底什么是IoT?我选取了维基百科，IBM公司，TI公司对IoT的定义，如下所述：

 维基百科：

The internet of things (IoT) is the internetworking of physical devices, vehicles (also referred to as "connected devices" and "smart devices"), buildings and other items- embedded with electronics,software, sensors, actuators, and network connectivity that enable these objects to collect and exchange data. In 2013 the Global Standards Initiative on Internet of Things  defined the IoT as "the infrastructure of the information society." The IoT allows objects to be sensed and/or controlled remotely across existing network infrastructure,creating opportunities for more direct integration of the physical world into computer-based systems, and resulting in improved efficiency, accuracy and economic benefit.

  IBM：

“It’s not so much about the emergence of new technology, it’s the convergence —the ability to use sensors for everything in the world to basically be a computer, whether it’s your contact

lens, your hospital bed, or a railway track.

 TI:

          Things, people and cloud services getting connected via the Internet to enable new use cases and business models.IoT is about harmonizing the way humans and machines connect using common public services

 对比可知，维基百科对IoT做了比较全面的解释，而IBM和IT在理解上更带有总结和可视化色彩。我们初步这么去理解：IoT就是让万物互联，为我所用。

internet of things，对这个things的理解尤为重要，因为它是物联网的源泉。我们再次参考维基百科对“things”的解释：

"Things," in the IoT sense, can refer to a wide variety of devices such as heart monitoring implants, biochip transponders on farm animals, electric clams in coastal waters, automobiles with built in sensors, DNA analysis devices for environmental/food/pathogen monitoring or field operation devices that assist firefighters in search and rescue operations.Legal scholars suggest to look at "Things" as an "inextricable mixture of hardware, software, data and service".These devices collect useful data with the help of various existing technologies and then autonomously flow the data between other devices. Current market examples include home automation (also known as smart home devices) such as the control and automation of lighting, heating (like smart thermostat), ventilation, air conditioning (HVAC) systems, and appliances such as washer/dryers, ovens or refrigerators/freezers that use Wi-Fi for remote monitoring.

由此可知，things可理解为可以通过传感器获得的一切数据。到这里，我们已经触碰到了IoT的核心—data。为什么说data是核心。我会在给出IoT最基本的模型后进行解释。

如下图2 TI公司所给出模型

图2

现在我们结合上面的定义，来理解这个模型。在这个模型中，很显然things是源泉，也就是我们底层传感器所采集的数据，比如温度，湿度，你的位置，你家厨房的电饭煲开关状态，你亲人的血糖浓度等等数据。这些数据通过网关到达云端。这里就又涉及到了物联网必须的一个环节—云。多数情况下，我们称之为设备云，主要负责数据的存储与分析。就好比你在天空中有个大仓库，它能按照你的设计来存东西。当然，存储只是这个仓库的一个小功能，仓库最大的能力还是体现在它的智能分析上。那云另外一端连接什么呢？模型中给的是people,其实也可以是machines.人在物联网中的角色当然可以理解为“王”了，你可以从云上获取你想要的任何信息（如果云上存在），你可以打开离你千里之外的一盏灯，有一天你到了美国才想起你卧室的空调没关，你只需要在手机触摸几下，就可以关掉空调。噢，如果你懒得动手，就对手机说“请帮我关掉卧室的空调”也没问题。

 上文有提到，data是物联网的核心，因为整个IoT就是围绕数据在运行。如数据的捕获，传输，分析，安全等，所以很轻松的可以理解为什么说“大数据”时代已经到来。下面给出IoT的另外一种模型，以便更好理解 data的重要性。如图3所示

                         图3

 为了更好理解上面上面讲述的IoT操作过程，请参考图4中给出的应该模型。云左侧是device，云右侧是APP。APP控制device，就是这么简单。

图4

至此，关于IoT主要的过程介绍完毕，随着科技的发展，IoT在工业，制造业，农业，医药，环保，建筑等领域会扮演越来越重要的角色。

 如果再一次问你，什么是物联网时，可否理解成“万物互联，为我所用”呢？

结语：

 The purpose of the Internet of Things is to connect us more closely with the physical world. It shares information with us about the cars we drive, the tools we use, and the buildings we live in. But without cognitive computing, the usefulness of this information would be limited by its own complexity and scale. We would only be able to see slivers of insight. The rest would remain in the dark.

                                                         By Harriet Green, General Manager, IBM Watson IoT and Education                                                                                                                        

附： 五分钟解析IoT IBM http://www.iqiyi.com/v_19rrlitdwk.html#

International Data Corporation (IDC) is the premier global provider of market intelligence, advisory services, and events for the information technology, telecommunications, and consumer technology markets. IDC helps IT professionals, business executives, and the investment community to make fact-based decisions on technology purchases and business strategy.

参考文献

1.http://www.ibm.com/

2.http://www.ti.com/iot

3.https://www.digi.com

4.维基百科

5.A link to the Internet of Things            

  Avi Baum ，Embedded Connectivity Solutions Senior Architect and Technology Advisor Texas Instruments

6.The Internet of Things in the Cognitive Era:Realizing the future and full potential of connected devices     Harriet Green, General Manager, IBM WatsonIoT and Education