Smart home agreement summary, who will eventually "unified rivers and lakes"?

With the word "smart" quickly becoming popular, various manufacturers have also joined the ranks of the intelligent army. On June 30, Alibaba also announced the upcoming launch of smart speakers to create its own unique brand, adding more technological products to the Chinese market. This is after Apple released smart home speaker HomePod, Chinese companies have also begun to enter the field of smart home, smart home industry, instantly become surging. So what are the protocols for smart homes?

ZigBee protocol

Zigbee is an abbreviation of IEEE 802.15.4 protocol. It originates from the character's eight-character dance. The bee (bee) flies through the wings and “zigs” to “dance” the wings to communicate with their peers the position information of the pollen. ZigBee The similarities of the protocol with its features are renamed ZigBee. ZigBee is mainly suitable for the field of automatic control and remote control. It can be embedded in various devices. Its characteristics are close to the propagation distance, low power consumption, low cost, low data rate, self-organizing network, and simple protocol.

The main advantages of ZigBee are as follows:

Low power consumption

Compared with Bluetooth and WiFi, under the same power (two AA batteries) can support the device to use six months to two years or so, while Bluetooth can only work for several weeks, WiFi can only work for a few hours.

2. Low cost

ZigBee patent fee is free, the transmission rate is small and the protocol is simple, which greatly reduces the cost of ZigBee equipment.

3. Dropping rate is low

Because ZigBee avoids the collision mechanism, and at the same time reserves a dedicated time gap for the fixed bandwidth of the communication service, no contention or collision occurs during data transmission; the function of the ad hoc network allows each node module to have Can establish the connection, the received information can be transmitted through the line between each node module, making the reliability of ZigBee transmission information greatly improved, it can be considered that it will not be dropped.

4. Strong networking capability

ZigBee has superior networking capabilities, and each of the established networks has 60,000 nodes.

5. Security

ZigBee provides a set of security classes and software based on 128-bit AES algorithms and integrates the security elements of IEEE 802.15.4.

6. Flexible working frequency band

The 2.4 GHz, 868 MHz and 915 MHz bands are all unlicensed.

The disadvantages of ZigBee are as follows:

Spread distance

If the power amplifier is not suitable, the effective propagation distance of ZigBee is generally 10m-75m, which is mainly applicable to small areas such as homes and offices. However, under the premise of sacrificing the advantage of low drop-rate, using the node module as the receiving end also serves as the transmitting end, it can realize longer distance information transmission.

2. Low data transmission rate

In the 2.4 GHz band, ZigBee also has a propagation speed of only 250 Kb/s, and this is simply the rate on the link and does not include frame overhead, channel contention, acknowledgment, and retransmission, which are actually applicable after removing these. The rate will be less than 100 Kb/s, and the rate will be shared by multiple nodes when running multiple applications.

3. There will be delay

ZigBee does not support the time division multiplexing channel access method while randomly accessing the MAC layer. Therefore, when supporting some real-time applications, delays may occur due to sending multiple hops and collisions.

Bluetooth (Bluetooth Protocol)

The Bluetooth protocol was created by Ericsson and developed Bluetooth technology standards with other industry-leading developers on May 20, 1999. It eventually named the wireless communication technology Bluetooth. Bluetooth technology is a wireless communication technology that enables electronic devices to establish network connections and transmit data or voice calls in a space of 10 to 100 meters.

The advantages of Bluetooth are as follows:

1. Low power consumption and fast transfer rate

The short data packet characteristic of Bluetooth is the fundamental of its low-power technology features, the transmission rate can reach 1Mb/s, and all connections use advanced sniffing sub-rating mode to achieve ultra-low duty cycle.

2. Short time to establish a connection

It takes only a short 3ms for the Bluetooth application to open and establish a connection, and at the same time it can complete the approved data transfer with a transmission speed of several milliseconds and immediately close the connection.

3. Good stability

The Bluetooth low energy technology uses a 24-bit Cyclic Repeat Check (CRC) to ensure maximum stability of all packets in the event of interference.

4. High safety

CCM's AES-128 full encryption technology provides high degree of encryption and authentication for data packets.

The disadvantages of Bluetooth are as follows:

1. The size of data transmission is limited

High-speed frequency hopping allows Bluetooth to transmit information with extremely high security, but it also limits the possibility that packets cannot be too large during Bluetooth transmission. Even in the so-called high-fidelity Bluetooth headset, high and low frequencies are severely compressed.

2. The number of device connections is small

Compared with Wifi and ZigBee, Bluetooth connectivity equipment is indeed poor, in theory, can connect eight devices, in fact, it can only do 6 - 7 device connections.

3. Single connectivity of Bluetooth devices

Assume that I use a mobile phone to connect a Bluetooth device, then B phone is not connected to it, I must be a handshake agreement with the Bluetooth device to disconnect the B phone to connect it.

WiFi (wireless fidelity protocol)

WiFi is an abbreviation of IEEE 802.11. It is a short-range wireless transmission technology capable of supporting data, images, voice, and multimedia with an output rate of up to 54 Mb/s, allowing Internet accessers to receive radio signals within a few hundred meters. The first version of WiFi was introduced in 1997 when it defined the physical layer and medium access control layer (MAC layer), and standardized the media access layer (MAC) while defining the basic transmission medium and network structure of the wireless LAN. The characteristics and physical layer (PHY), in which the physical layer uses FSSS (Frequency Modulation Spread Spectrum) technology, infrared technology and DSSS (Direct Sequence Spread Spectrum) technology. In 1999, the IEEE 802.11g and IEEE 802.11a standards were added to improve.

WiFi advantages:

1. Wide range of transmission

WiFi's radio coverage radius is up to 100 m. Even the entire building can be covered. Compared to the radius of only 15m Bluetooth, the advantage is quite obvious.

2. Fast transmission speed

Up to 54Mb/s transfer rate allows WiFi users to receive the network anytime and anywhere, and can quickly enjoy a series of broadband information similar to online games, video on demand (VOD), distance education, online securities, telemedicine, video conferencing, etc. Value-added services. In this rapidly evolving information era, WiFi, which is constantly improving in speed, must meet the needs of social and personal information development.

3. Health and safety

WiFi devices cannot transmit more than 100 mW under IEEE 802.11, and actual transmit power may be between 60 and 70 mW. Compared with similar communication devices, the mobile phone's transmit power is about 200 mW to 1 W, while the handheld radio is up to 5 W. Compared to the two WiFi products, radiation is smaller.

4. High popularity

Nowadays, more and more electronic devices are equipped with WiFi, and mobile phones, laptops, tablet computers, and MP4s almost all include WiFi in their mainstream standard configurations.

WiFi disadvantages:

1. High power consumption

2 expensive

3. Protocol coding complexity

LPWAN (Low Power Wide Area Internet of Things)

The world's largest chip makers Intel, Qualcomm, global communications equipment giants Huawei, Nokia, Ericsson, and global carrier giants Vodafone, China Mobile, etc. all accelerate the commercialization of low-power wide area network (LPWAN), and the LPWAN protocol standard has also achieved substantial Progress, 2016 will be a major milestone in the development of LPWAN. By then, not only will applications in various industries increase rapidly, but also parts of Wi-Fi, Bluetooth and Zigbee connections will be replaced by LPWAN connections.

UWB (Ultra Wideband)

UWB is a carrierless communication technology that uses nanosecond to picosecond non-sinusoidal narrow pulses to transmit data. By transmitting very low-power signals over a wide spectrum, UWB can achieve data transfer rates of hundreds of Mbit/s to several Gbit/s in a range of about 10 meters.

Z-Wave protocol

Z-Wave is a wireless networking specification dominated by the Danish company Zensys. Although the Z-wave Alliance has no ZigBee Alliance's strength, members of the Z-wave Alliance have already had current products in the smart home area. The company has more than 160 internationally renowned companies and its scope basically covers all countries and regions in the world. The current domestic application is not only light.

RF RF protocol

The more common applications of RF radio protocols are radio frequency identification (RFID), often called inductive electronic chip or proximity card, proximity card, contactless card, electronic tag, electronic bar code, and so on. The principle is that the scanner emits radio wave energy of a specific frequency to the receiver to drive the receiver circuit to send the internal code, and the scanner receives the code.

EnOcean Agreement

The International Electrotechnical Commission adopted the EnOcean wireless communication standard as the international standard ISO/IEC 14543-3-10, which is the only wireless international standard that uses energy harvesting technology.

ModBus protocol

It was invented by Modicon (now a brand of Schneider Electric) in 1979 and is the world's first bus protocol that is truly used in industrial sites. ModBus network is an industrial communication system, which is composed of programmable controllers and computers with intelligent terminals connected through public lines or local dedicated lines. Its system structure includes both hardware and software. It can be applied to various data acquisition and process monitoring.

KNX protocol

In May 1999, the European three major bus protocols EIB, BatiBus and EHSA merged to form the Konnex Association and proposed the KNX protocol. The agreement is based on EIB, taking into account the physical layer specifications of BatiBus and EHSA, and absorbing the advantages of configuration modes in BatiBus and EHSA, providing a complete solution for home and building automation.

Weave agreement

Weave is a low-power, low-bandwidth, low-latency, secure device-to-device communications protocol originally developed by Nest and used on their own devices. Nest opened it to developers around the world. Currently acquired by Google, Google decided to launch Weave, a communication language based on JSON. It is intended to create common communication and instruction transceiving solutions between smart hardware, compatible with Android.

Thread agreement

Launched jointly by Samsung, Nest, ARM, Big Ass Fans, Freescale and Silicon Labs, it is an IP-based wireless network protocol for connecting home smart products.

Conclusion

Currently, various types of protocols have application scenarios in their respective fields. No one will completely replace them. It can be foreseen that with the development of smart devices, a low-power wifi version protocol will eventually replace the above protocols. Such as Thread and other agreements, we will wait and see.