Thead 1 概述

1） 什么是Thread？
Thread is an IP based wireless networking protocol designed for low-power connected products in home automation space.

2) Thread 和Zigbee有什么区别？
相同点：
-They are both mesh local area networks.
-They use the same low-level MAC layer protocol—IEEE 802.15.4. -(This means they can sometimes use the same chips.)
-They are both open standards.
-They’ve both targeted similar application types, like smart homes.
-They both run on the global-standard 2.4 GHz ISM frequency band.Their power consumption and usage may be very similar.

不同点：
在网络层：Thread是基于Ip地址的，Zigbee是非Ip地址
在应用层：Thread没有定义应用层，Zigbee有应用层
software stack：Thread相比Zigbee简单

1. Thread 的网络结构？
   

Boarder Router:提供802.15.4 网络向其他邻近网络（wifi,Ethernet,etc）的转换，通常有1个或者多个boarder router

Routers: Routers provide routing services to network devices. Routers also provide joining and security services for devices trying to join the Thread Network. Routers are not designed to sleep. Routers can downgrade their functionality and become REEDs (Router-Eligible End Devices).

Router-Eligible End Devices:
REEDs can become routers but due to the network topology or conditions these devices are not acting as routers. As such, a REED is not a specific device type but a state of a routing- capable device when in the Thread Network. These devices do not forward messages or provide joining or security services for other devices in the network. If necessary, the network manages the transition of a device from REED to router without user interaction.

Sleepy End Devices:
Sleepy End Devices (SEDs) are host devices. They communicate only through their parent router and cannot forward messages for other devices

1. Thread 的security有哪些？

2. Thread的Mesh和BLE的Mesh有什么区别？

3. 使用ＩＰ有什么好处？
   

参考：
1.https://www.link-labs.com/thread-vs-zigbee-for-iot-engineers/
2.