【ember zigbee】第一章：ug103-01-fundamentals-wireless-network 学习笔记

本文链接：https://blog.youkuaiyun.com/tainjau/article/details/90943269

文章目录

1、 Overview

As embedded system design has evolved and the Internet of Things (IoT) has emerged, the need for networking support has become a basic design requirement. Like more general-purpose computers, embedded systems have moved toward wireless networking.
Most wireless networks have pushed toward ever-higher data rates and greater point-to-point ranges. But not all design applications require high-end wireless networking capabilities. Low-data-rate applications have the potential to outnumber the classic high-data-rate wireless networks worldwide.

随着嵌入式系统设计的发展和物联网（IoT）的出现，对网络支持的需求已成为基本的设计要求。与更多通用计算机一样，嵌入式系统已经转向无线网络。
大多数无线网络已经推出了更高的数据速率和更大的点对点范围。但并非所有设计应用都需要高端无线网络功能。低数据速率应用程序有可能超过全球经典的高数据速率无线网络。

Simple applications such as lighting control, smart utility meters, Heating, Ventilation, and Air Conditioning (HVAC) control, fire/smoke/CO alarms, remote doorbells, humidity monitors, energy usage monitors, and countless others devices function very well with low-data-rate monitoring and control systems. The ability to install such devices without extensive wiring decreases installation and maintenance costs. Increased efficiencies and cost savings are the primary motives behind this applied technology.

就比如简单的应用：如照明控制，智能公用事业仪表，供暖，通风和空调（HVAC）控制，火灾/烟雾/ CO报警，远程门铃，湿度传感器，能源使用监控器，以及无数其他设备的功能非常好的数据速率监测和控制系统。无需大量布线即可安装此类设备，降低了安装和维护成本。提高效率和节省成本是这种应用技术背后的主要动机。
ps：事实上，智能家居所使用的设备，大多数情况下，数据吞吐量并不高，

A wireless sensor network (WSN) is a wireless network consisting of distributed devices using sensors at different locations to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion, or pollutants.
In addition to one or more sensors, each node in a sensor network is typically equipped with a radio transceiver or other wireless communications device, a small microcontroller, and an energy source, usually a battery.

无线传感器网络（WSN）是由分布式设备组成的无线网络，所述分布式设备使用位于不同位置的传感器来协作地监视物理或环境条件，例如温度，声音，振动，压力，运动或污染物。
除了一个或多个传感器之外，传感器网络中的每个节点通常配备有无线电收发器或其他无线通信设备，小型微控制器和能量源，通常是电池。

The size of a single sensor node can vary from shoebox-sized nodes down to devices the size of coins. The cost of sensor nodes is similarly variable, depending on the size of the sensor network and the complexity required of individual sensor nodes.
Size and cost constraints on sensor nodes result in corresponding constraints on resources such as energy, memory, computational speed, and bandwidth.

单个传感器节点的大小可以从鞋盒大小的节点到硬币大小的设备变化。传感器节点的成本同样可变，这取决于传感器网络的大小和各个传感器节点所需的复杂性。
传感器节点的尺寸和成本约束导致了对功耗，存储器，计算速度和带宽等资源需要有所限制。

Wireless personal area networks have emerged partially as a result of the IEEE 802.15.4 standard for low data rate digital radio connections between embedded devices.
Above the medium access control (MAC) and physical (PHY) layers, there have been a number of standards formed such as The Zigbee Alliance and the Thread Group, which were formed to standardize industry efforts to supply technology for networking solutions that are based on 802.15.4, have low data rates, consume very little power, and are therefore characterized by long battery life.
The Zigbee Standard makes possible complete and cost-effective networked homes and similar buildings where all devices are able to communicate for monitoring and control. The Thread Group brings IPv6 to these small embedded devices.

因此出现了以IEEE 802.15.4标准，用于嵌入式设备之间的低数据速率无线通信的无线个域网。
在媒体访问控制（MAC）和物理（PHY）层之上，已经形成了许多标准，例如Zigbee联盟和其相关的协议栈，这些标准的形成是为了标准化行业，努力为基于的网络解决方案提供技术。基于802.15.4标准的无线设备，具有低数据速率，消耗非常少的功率，因此具有长电池寿命的特征。
Zigbee标准使得所有设备能够进行通信以进行监控和控制的完整且经济高效的联网住宅和类似建筑成为可能。 Thread Group为这些小型嵌入式设备带来了IPv6。

2、Embedded Networking

2.1、嵌入式网络的简要介绍

While the term wireless network may technically be used to refer to any type of network that functions without the need for interconnecting wires, the term most commonly refers to a telecommunications network, such as a computer network. Wireless telecommunications networks are generally implemented with radios for the carrier or physical layer of the network.

虽然在术语上，无线网络在技术上可用于指代无需连接电线即可运行的任何类型的网络。但术语最通常是指电信网络，例如计算机网络。无线电信网络通常用无线电实现，用于网络的载波或物理层。

One type of wireless network is a wireless local area network or LAN.
It uses radios instead of wires to transmit data back and forth between computers on the same network.
The wireless LAN has become commonplace at hotels, coffee shops, and other public places.
The wireless personal area network (WPAN) takes this technology into a new area where the distances required between network devices is relatively small and data throughput is low

一种类型的无线网络是无线局域网或LAN。它使用无线电而不是电线在同一网络上的计算机之间来回传输数据。
无线局域网在酒店，咖啡店和其他公共场所已经司空见惯。无线个域网（WPAN）将这项技术带入了一个新的领域，网络设备之间所需的距离相对较小，数据吞吐量较低。

In the control world, embedded systems have become commonplace for operating equipment using local special-purpose computer hardware.
Wired networks of such devices are now common in manufacturing environments and other application areas.
Like all computer networks, the interconnecting cable systems and supporting hardware are messy, costly, and sometimes difficult to install.
To overcome these problems, wireless networking of embedded systems (that is, embedded networking) has become commonplace.
However, the costly embedded networking solutions have only been justifiable in high-end applications where the costs are a secondary consideration.
Low-cost applications with low data rate communications requirements did not have a good standardized solution until the IEEE 802.15.4 standard for wireless personal area PHY and MAC layers was released in 2003.
Note: The current version as of this writing is the IEEE 802.15.4-2006 standard (https://standards.ieee.org/standard/802_15_4-2006.html)

在控制领域，嵌入式系统已经成为使用本地专用计算机硬件操作设备的常见系统。这种设备的有线网络现在在制造环境和其他应用领域中很常见。
与所有计算机网络一样，互连电缆系统和支持硬件是混乱的，昂贵的，并且有时难以安装。
为了克服这些问题，嵌入式系统的无线网络（即嵌入式网络）已经变得司空见惯。然而，昂贵的嵌入式网络解决方案仅在成本是次要考虑因素的高端应用中才是合理的。
在2003年发布用于无线个域PHY和MAC层的IEEE 802.15.4标准之前，具有低数据速率通信要求的低成本应用没有良好的标准化的解决方案。
ps:ieee802.15.4的协议文档，这个网站似乎进不去了，但是我之前的文章里面有提到这篇文章，可以在这里下载。https://download.youkuaiyun.com/download/tainjau/10578440

2.2、zigbee标准

The Zigbee Alliance was formed to establish networking and application-level standards on top of the IEEE 802.15.4 standards, to allow flexibility, reliability, and interoperability. The Zigbee 802.15.4-2003 Specification 1.0 was ratified in 2005 and the Zigbee 2006 Specification was announced in 2006, obsoleting the 2004 stack.
Working Groups (WGs) have been formed within the Internet Engineering Task Force (IETF) to establish open standard approaches for routing (roll WG) and interfacing low-powered wireless devices to IPV6 networks (6LoWPAN WG).
More recently, the Thread Group was formed in 2014 to utilize open IP standards, mesh networking, and 802.15.4 to support a wide array of home networking products.

Zigbee联盟的成立是为了在IEEE 802.15.4标准之上建立网络和应用级标准，以实现灵活性，可靠性和互操作性。 Zigbee 802.15.4-2003规范1.0于2005年获得批准，2006年宣布了Zigbee 2006规范，淘汰了2004年的协议栈。
Working Groups （WG）已在互联网工程任务组（IETF）内成立，以建立开放标准的路由方法（roll WG）和低功率无线设备与IPV6网络（6LoWPAN WG）的接口。
最近，Thread Group成立于2014年，旨在利用开放式IP标准，网状网络和802.15.4来支持各种家庭网络产品。
ps:截至目前，zigbee的协议栈版本是zigbee3.0

2.3、无线通信的缺点及应对方法

Although wireless networks eliminate messy cables and enhance installation mobility, the downside is the potential for interference that might block the radio signals from passing between devices. This interference may be from other wireless networks or from physical obstructions that interfere with the radio communications. Interference from other wireless networks can often be avoided by using different channels.
Zigbee, for example, has a channel-scanning mechanism on start-up of a network to avoid crowded channels. Standards-based systems, such as Thread, Zigbee and Wi-Fi, use mechanisms at the MAC layer to allow channel sharing. In addition, Zigbee and Thread provide an interoperable standard for multi-hop wireless networking, allowing signals to reach their destination by traveling through multiple relay points.
These networks can be comprised of many such relay points or “routers,” each one within range of one or more other routers, creating an interconnected “mesh” of devices that can provide redundant paths for data within the network that are automatically rediscovered and used to avoid interference in a local area. This concept is collectively referred to as “mesh networking.”

尽管无线网络消除了凌乱的电缆并增强了安装的移动性，但缺点是可能会阻止无线电信号在设备之间传递。这种干扰可能来自其他无线网络或来自干扰无线电通信的物理障碍。通常可以通过使用不同的信道来避免来自其他无线网络的干扰。
例如，Zigbee在网络启动时具有通道扫描机制，以避免拥挤的通道。基于标准的系统，例如线程，Zigbee和Wi-Fi，使用MAC层的机制来允许信道共享。此外，Zigbee和Thread为多跳无线网络提供了可互操作的标准，允许信号通过多个中继点到达目的地。
这些网络可以包括许多这样的中继点或“路由器”，每个都在一个或多个其他路由器的范围内，创建一个互连的“网格”设备，可以为网络中的数据提供自动重新发现和使用的冗余路径避免局部干扰。这个概念统称为“网状网络”。
ps:这里提及zigbee的特点：自组网能力。

Another potential problem is that wireless networks may be slower than those that are directly connected through a cable. Yet not all applications require high data rates or large data bandwidth. Most embedded networks function very well at reduced throughputs. Application designers need to ensure their system data rates are within the range achievable with the system being used.
Wireless network security is also a problem, because the data can easily be overheard by eavesdropping devices. Zigbee and Thread have a set of security services designed around Advanced Encryption Standard (AES) 128 encryption, so that application designers have a choice of security levels based on the needs of their applications. Careful design around these standards helps maintain high levels of network security.

另一个潜在的问题是无线网络可能比通过电缆直接连接的网络慢。然而，并非所有应用都需要高数据速率或大数据带宽。大多数嵌入式网络在降低吞吐量时运行良好。应用程序设计人员需要确保其系统数据速率在使用系统时可实现的范围内。
无线网络安全也是一个问题，因为窃听设备很容易听到数据。 Zigbee和Thread拥有一套围绕高级加密标准（AES）128加密设计的安全服务，因此应用程序设计人员可以根据应用程序的需求选择安全级别。围绕这些标准的精心设计有助于保持高水平的网络安全性。

2.3、蓝牙和zigbee对比

Other networking standards exist such as Bluetooth Classic. Each standard has its own unique strengths and essential areas of application. The bandwidth of Bluetooth is 1 Mbps, while 802.15.4 based protocols are one-fourth of this value.
The strength of Bluetooth Classic lies in its ability to allow interoperability and replacement of cables. Zigbee and Threads strengths are low cost, long battery life, and mesh networks for large network operation. Bluetooth is meant for point-to-point applications such as handsets and headsets, whereas Zigbee and Thread are focused on the sensors and remote controls market, large distributed networks, and highly reliable mesh networking.
Bluetooth Low Energy is emerging rapidly as another low power wireless technology very well suited for point-topoint applications such as controlling a single device with your smartphone.

一些其他的网络标准，例如蓝牙。每个标准都有自己独特的优势和必要的应用领域。蓝牙的带宽为1 Mbps，而基于802.15.4的协议带宽仅为此值的四分之一。
蓝牙的优势在于它能够实现互联互通和更换电缆。 Zigbee和Threads的优势在于成本低，电池寿命长，以及用于大型网络运营的网状网络。蓝牙适用于手机和耳机等点对点应用，而Zigbee和Thread则专注于传感器和遥控器市场，大型分布式网络以及高度可靠的网状网络。蓝牙低功耗作为另一种低功耗无线技术迅速崛起，非常适合点对点应用，例如使用智能手机控制单个设备。

While in the past each chip supported a single protocol, new developments have allowed two protocols to operate on the same chip.
This multiprotocol operation may be as simple as chip technology that supports different protocols, with the application protocol of choice loaded during manufacturing. More recently, chips such as Silicon Labs EFR32 products and shared operational infrastructure allow two protocols to share the same radio. For example, a dynamic multiprotocol implementation might allow an end user to use a smartphone app working with a Bluetooth Low Energy application on the device to control the device or perform diagnostics, while the device remains connected to its Zigbee home automation network. UG103.16: Multiprotocol Fundamentals describes the four different multiprotocol modes, their operational requirements, and discusses some considerations to take into account when implementing a multiprotocol device.

虽然过去每个芯片都支持单一协议，但新的开发允许两个协议在同一芯片上运行。
这种多协议操作可以像支持不同协议的芯片技术一样简单，在制造期间加载选择的应用协议。最近，诸如Silicon Labs EFR32产品和共享运营基础设施等芯片允许两种协议共享相同的无线电。
例如，动态多协议实施可能允许最终用户使用在设备上使用蓝牙低功耗应用程序的智能手机应用来控制设备或执行诊断，同时设备仍然连接到其Zigbee家庭自动化网络。-
UG103.16：多协议基础描述了四种不同的多协议模式，它们的操作要求，并讨论了在实现多协议设备时要考虑的一些注意事项。

3、Radio Fundamentals

Radio is the wireless transmission of signals by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic waves are, in the case of radio, a form of non ionizing radiation, which travels by means of oscillating electromagnetic fields that pass through electrical conductors, the air, and the vacuum of space. Electromagnetic radiation does not require a medium of transport like a sound wave. Information can be imposed on electromagnetic waves by systematically changing (modulating) some property of the radiated waves, such as their amplitude or their frequency. When radio waves pass an electrical conductor, the oscillating fields induce an alternating current in the conductor. This can be detected and transformed into sound or other signals that reproduce the imposed information.

无线电是通过调制频率低于可见光的电磁波来无线传输信号。在无线电的情况下，电磁波是一种非电离辐射，其通过穿过电导体，空气和空间真空的振荡电磁场传播。电磁辐射不需要像声波那样的传输介质。通过系统地改变（调制）辐射波的某些特性，例如它们的幅度或频率，可以对电磁波施加信息。当无线电波通过电导体时，振荡场在导体中感应出交流电。这可以被检测并转换成声音或其他信号，以再现强加的信息。

The word ‘radio’ is used to describe this phenomenon and radio transmission signals are classed as radio frequency emissions. The range or spectrum of radio waves used for communication has been divided into arbitrary units for identification. The Federal Communications Commission (FCC) and National Telecommunications and Information Association (NTIA) define the radio spectrum in the United States as that part of the natural spectrum of electromagnetic radiation lying between the frequency limits of 9 kilohertz and 300 gigahertz, divided into various sub-spectrums for convenience.

“无线电”一词用于描述这种现象，无线电传输信号被归类为射频发射。用于通信的无线电波的范围或频谱已被分成单元以进行识别。
美国联邦通信委员会（FCC）和国家电信和信息协会（NTIA）将美国的无线电频谱定义为位于9千赫兹至300千兆赫兹频率范围之间，为方便起见，分成各种子频谱。
以下名称通常用于标识各种子谱：
上面列出的每个子谱进一步细分为许多其他子部分或“带”。例如，美国AM广播频带从535 kHz扩展到1705 kHz，这属于被归类为中频的频谱部分。

3.1、频段

无线电频谱由政府机构和国际条约监管。大多数发射台，包括商业广播公司，军事，科学，工业和业余无线电台，都需要许可才能运营。每个许可证通常定义操作类型，功率电平，调制类型的限制，以及分配的频带是保留用于专用还是共享使用。三个频段可用于发射无线电信号，无需美国政府许可。
在这里插入图片描述
常见的策略是在住宅和家庭环境中使用2400 MHz。 Zigbee联盟和线程组支持使用这个频段，两者都在寻找其他SubGHz频段以扩展其功能。

3.2、信号调制

Modulation is the process of changing the behavior of a signal so that it transfers information. Modulation can also be thought of as a way to encode information to be transmitted to a receiver that decodes, or demodulates, the information into a useful form.

调制是改变信号行为以便传输信息的过程。调制还可以被认为是将要发送到接收器的信息编码的方式，该接收器将信息解码或解调成有用的形式。

The basic radio frequency (RF) signal has a fundamental frequency that can be visualized as an alternating current whose frequency is referred to as the carrier wave frequency.
The earliest method used for encoding information onto the carrier wave involved switching the carrier wave on and off in a specific time duration pattern. This was known as continuous wave (CW) mode.
The carrier frequency can also be varied in its amplitude (that is, signal strength) or its frequency. These two modulation methods are called amplitude modulation (AM) and frequency modulation (FM), respectively.
It is possible to impose a signal onto the carrier wave using these three basic modulation techniques and creative variations of these techniques.

基本射频（RF）信号具有可以被视为交流电的基频，其频率被称为载波频率。
用于将信息编码到载波上的最早方法涉及在特定持续时间模式中接通和断开载波。这被称为连续波（CW）模式。
载波频率也可以在其幅度（即信号强度）或其频率上变化。这两种调制方法分别称为幅度调制（AM）和频率调制（FM）。使用这三种基本调制技术和这些技术的创造性变化，可以将信号施加到载波上。

The Silicon Labs EFR32 and EM3x integrated circuit families uses a form of offset quadrature phase-shift keying (OQPSK) to modulate the carrier wave. Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal such as the carrier wave. PSK is a derivative of FM techniques.

Silicon Labs EFR32和EM3x集成电路系列使用一种偏置正交相移键控（OQPSK）来调制载波。相移键控（PSK）是一种数字调制方案，其通过改变或调制诸如载波的参考信号的相位来传送数据。 PSK是FM技术的衍生物。

All digital modulation schemes use a finite number of distinct signals to represent digital data. In the case of PSK, a finite number of phases are used.
Each of these phases is assigned a unique pattern of binary bits. Usually, each phase encodes an equal number of bits. Each pattern of bits forms the symbol that is represented by the particular phase.
The demodulator, which is designed specifically for the symbol set used by the modulator, determines the phase of the received signal and maps it back to the symbol it represents, thus recovering the original data.
To do so, the receiver must compare the phase of the received signal to a reference signal. Such a system is termed coherent.

所有数字调制方案都使用有限数量的不同信号来表示数字数据。在PSK的情况下，使用有限数量的相位。
为这些阶段中的每一个分配唯一的二进制位模式。通常，每个阶段编码相同数量的比特。每个比特模式形成由特定阶段表示的符号。
专门为调制器使用的符号集设计的解调器确定接收信号的相位并将其映射回它所代表的符号，从而恢复原始数据。为此，接收器必须将接收信号的相位与参考信号进行比较。这种系统被称为连贯的。

3.3、天线

在这里插入图片描述

天线是设计用于发射或捕获电磁波的电导体的布置。天线发射可由另一天线检测的信号的能力被称为无线电传播。天线根据工作频率制成一定的尺寸。来自2400 MHz无线电的天线无法在5800 MHz无线电上有效使用，反之亦然。然而，来自一种2400MHz技术的天线，例如Wi-Fi或蓝牙，可以用于另一种2400MHz技术，例如Zigbee或Thread。
参考特定的三维空间描述了两种基本类型的天线：
•全方位：在所有方向均匀辐射
•单向（也称为方向）：在一个方向上的辐射比在另一个方向上的辐射更多。所有天线在自由空间的所有方向上辐射一些能量，但仔细的构造导致在某些方向上的能量的大量传输和在其他方向上辐射的可忽略的能量。
通常，由于网状网络的性质，期望全向天线提供尽可能多的通信路径。

3.4、信号的传输距离

在这里插入图片描述

无线电信号的传播距离和可传输的信息量基于：
- 天线向空中传输的功率。
- 发射站和接收站之间的距离。
- 接收无线电需要多少无线电信号强度。
- 阻碍了哪些类型的物理/电气障碍物

3.4.1、无线电发射功率

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无线电发射功率以瓦特为单位测量，并且通常以dBm为单位进行讨论，分贝以1毫瓦为基准。将瓦数转换为dBm允许使用简单的加法和减法进行无线电链路计算（dBm = 10 * log10（P / 0.001））。
例如，典型的功率放大无线电卡以100毫瓦（或毫瓦）的速度传输，这意味着功率输出为
20dBm的。
如果1 mW或0 dBm是以分贝为单位的功率基准，则+3 dBm是1 mW以上的某个功率级别（具体为2 mW）。这是EM3x器件的标准输出功率。在升压模式下，可以在EM3x平台上将其增加到+8 dBm或6 mW。使用功率放大器模块可以将发射功率增加到20 dBm，但这需要更多的功率来运行。 EFR32平台包括一些+13 dBm的变体和其他高达+20 dBm的变体，两者都没有外部功率放大器的帮助。

3.4.2、信号衰弱

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无线电还需要强调才能被检测到。接收器理解数据所需的最小信号强度称为接收灵敏度。
当无线电信号在空中传播时，它会减弱。当无线电信号离开发射天线时，dBm是一个高数字（例如，20dBm）。当它在空中传播时，它会失去力量并下降到负数。在某些时候，达到dBm的最小值，低于该值，无线电将无法成功接收传输。该值表示“接收灵敏度”或“Rx灵敏度”。该值将随所用无线电的类型而变化，但通常在-90dBm和-100dBm之间。（有关特定的接收灵敏度数据，请参阅无线电芯片的数据表。）
如果您可以使发送功率达到-75dBm，并且无线电的接收灵敏度具有-95dBm，您将获得20dBm的额外信号以适应干扰和其他问题。

3.4.3、无线信号能传输多远距离

如果您知道断电和接收器灵敏度，则可以确定是否可以在给定距离内进行广播。在以下示例中，您想知道是否可以接收超过五英里的信号。为此，您需要知道无线电发射器和接收器之间的可用空间损耗。
例如，5英里处2.4 GHz信号的自由空间损耗为118.36 dB。因此，您可以估算网络范围内的信号强度：
EmberZNet和Silicon Labs Thread SDK（软件开发套件）附带功能测试应用程序（“NodeTest”），可用于在几乎任何环境中对嵌入式无线网络执行经验范围测试。（参见文档AN1019：使用NodeTest应用程序获取有关使用NodeTest的信息。）Silicon Labs建议在预期的环境中进行基本范围测试，以评估是否需要扩展范围。

4、Networking: Basic Concepts

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网络是计算机和其他设备（例如打印机和调制解调器）的系统，它们以可以交换数据的方式连接。该数据可以是信息性的或面向命令的，或两者的组合。
网络系统由硬件和软件组成。网络上的硬件包括物理设备，如计算机工作站，外围设备和充当文件服务器，打印服务器和路由器的计算机。这些设备都称为网络上的节点。
如果节点未全部连接到单个物理电缆，则特殊硬件和软件设备必须连接不同的电缆，以便将消息转发到其目标地址。桥接器或中继器是连接网络电缆而不检查消息地址或决定消息的最佳路径的设备。相反，路由器包含寻址和路由信息，使其能够从消息的地址确定消息的最有效路由。在将消息传递到目标目标之前，可以将消息从路由器多次传递到路由器。
为了使节点交换数据，它们必须使用一组共同的规则来定义数据的格式以及数据的传输方式。协议是用于数据交换的形式化的程序规则集。该协议还为网络互连节点之间的交互提供规则。网络软件开发人员在执行协议所需功能的软件应用程序中实现这些规则。
路由器只有在使用相同的协议和地址格式时才能连接网络，而网关会转换地址和协议以连接不同的网络。这样的一组互连网络可以称为因特网，内联网，广域网（WAN）或其他专用网络拓扑。互联网一词通常用于指全球最大的网络系统，也称为万维网。用于实现万维网的基本协议称为Internet协议或IP。
网络协议通常使用另一种更基本的协议的服务来实现其目的。例如，传输控制协议（TCP）使用IP封装数据并通过IP网络传输数据。使用底层协议服务的协议被认为是较低协议的客户端;例如，TCP是IP的客户端。以这种方式相关的一组协议称为协议栈。

5、Wireless Networking

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无线网络模仿有线网络，但使用无线电信号替换有线网络作为数据互连介质。协议基本上与有线网络中使用方式的相同，尽管添加了一些附加功能，因此两种类型的网络仍然可以互操作。然而，已经出现了无线网络，其没有需要互操作性的有线对应物。这些专用网络具有其自己的硬件和软件基础，以在其独特环境的范围内实现可靠的联网。
注意：大多数网络协议在某种程度上都基于开放式互连系统（OSI）模型。

6、Networking Devices

Silicon Labs has developed networking hardware (the EFR32xG and EM3x families) and SDKs (the EmberZNet SDK, Silicon Labs Thread
SDK, Flex SDK, and other stacks and application development tools) to facilitate implementation of a wireless personal area network of devices for sensing and control applications. The following figure represents a typical wireless device using Zigbee, one of the Silicon Labs networking technologies. The RF data modem is the hardware responsible for sending and receiving data on the network. The microcontroller represents the computer control element that originates messages and responds to any information received.
The sensor block can be any kind of sensor or control device. Such a system can exist as a node on a network without any additional equipment. Any two such nodes, with compatible software, can form a network. Large networks can contain thousands of such nodes.

Silicon Labs开发了网络硬件（EFR32xG和EM3x系列）和SDK（EmberZNet SDK，Silicon Labs Thread）SDK，Flex SDK和其他堆栈和应用程序开发工具），以便于实现用于传感和控制应用的设备的无线个域网。下图表示使用Silicon Labs网络技术之一的Zigbee的典型无线设备。 RF数据调制解调器是负责在网络上发送和接收数据的硬件。微控制器代表计算机控制元件，它发起消息并响应收到的任何信息。
传感器块可以是任何类型的传感器或控制设备。这样的系统可以作为网络上的节点存在而无需任何附加设备。具有兼容软件的任何两个这样的节点都可以形成网络。大型网络可以包含数千个这样的节点。

Chips such as the EM3x or EFR32xG family provide both the RF and microcontroller portions of the figure above. When used as “network coprocessors,” the chips provide only the RF and networking part of the system, acting as a co-processor to any microcontroller,Digital Signal Processing (DSP), or similar device required for the application.
For details of the various networking technologies, see the specific Fundamentals document(s) for that technology.