Z-Wave

Wireless standard for intelligent building networks
Like other protocols and systems aimed at the residential, commercial, MDU and building markets, a Z Wave system can be controlled from a smart phone, tablet, or computer, and locally through a smart speaker, wireless keyfob, or wall mounted panel with a Z Wave gateway or central control device serving as both the hub or controller. Z Wave provides the application layer interoperability between home control systems of different manufacturers that are a part of its alliance. There is a growing number of interoperable Z Wave products; over 1,700 in 2017, over 2,600 by 2019,

The Z Wave protocol was developed by Zensys, a Danish company based in Copenhagen, in 1999. That year, Zensys introduced a consumer light control system, which evolved into Z Wave as a proprietary system on a chip (SoC) home automation protocol on an unlicensed frequency band in the 900 MHz range. Its 100 series chip set was released in 2003, and its 200 series was released in May 2005, Its 500 series chip, also known as Z Wave Plus, was released in March 2013, with four times the memory, improved wireless range, improved battery life, an enhanced S2 security framework, and the SmartStart setup feature. Its 700 series chip was released in 2019, with the ability to communicate up to 100 meters directly from point to point, or 800 meters across an entire Z Wave network, an extended battery life of up to 10 years, and comes with S2 and SmartStart technology. In July 2019, the Z Wave Plus v2 certification was announced. It is designed for devices built on the 700 platform. The technology began to catch on in North America around 2005, when five companies, including Danfoss, Ingersoll Rand and Leviton Manufacturing, adopted Z Wave. Following the acquisition, Z Wave's U. S. headquarters in Fremont, California were merged with Sigma's headquarters in Milpitas, California. As part of the changes, the trademark interests in Z Wave were retained in the United States by Sigma Designs and acquired by a subsidiary of Aeotec Group in Europe. On January 23, 2018, Sigma announced it planned to sell the Z Wave technology and business assets to Silicon Labs for $240 million, and the sale was completed on April 18, 2018. In 2005, there were six products on the market that used Z Wave technology. By 2012, as smart home technology was becoming increasingly popular, there were approximately 600 products using Z Wave technology available in the U. S. The open source availability allows software developers to integrate Z Wave into devices with fewer restrictions. Z Wave's S2 security, Z/IP for transporting Z Wave signals over IP networks, and Z Wave middleware are all open source as of 2016. In 2020, the Z Wave Alliance ratified the Z Wave specification, adding the application to open source development. The Alliance Technical Working Group manages Z Wave specification development and maintains a library of standard implementations for Z Wave compliant products.

Established in 2005 and re incorporated as a non profit in 2020, the Z Wave Alliance is a member driven standards development organization dedicated to market development, technical Z Wave specification and device certification, and education on Z Wave technology. Z Wave Alliance is a consortium of over 300 companies in the residential and commercial connected technology market. Z Wave Alliance certifies devices to standards that guarantee interoperability with full backwards compatibility among all generations of Z Wave devices. These standards include specifications for reliability, range, power consumption, and device interoperability. In October 2013, a new protocol and interoperability certification program called Z Wave Plus was announced, based upon new features and higher interoperability standards bundled together and required for the 500 series system on a chip (SoC), and including some features that had been available since 2012 for the 300/400 series SoCs. In February 2014, the first product was certified by Z Wave Plus. In 2016, the Alliance launched a Z Wave Certified Installer Training program to give installers, integrators and dealers the tools to deploy Z Wave networks and devices in their residential and commercial jobs. That year, the Alliance announced the Z Wave Certified Installer Toolkit (Z CIT), a diagnostics and troubleshooting device that can be used during network and device setup and can also function as a remote diagnostics tool. Z Wave Long Range (LR) was announced in September 2020, a new specification with an increased range over regular Z Wave signals. The LR specification is managed and certified under the Z Wave Plus v2 certification. Z Wave Alliance maintains the Z Wave certification program. There are two components to Z Wave certification: technical certification and market certification. In December 2019, Z Wave announced the Z Wave Source Code Project, in which it would release the source code to its platform, for members to contribute to the advancement of the standard, under the supervision of the newly established OS Work Group. The project is available to alliance members on GitHub. In December 2019, the Z Wave Alliance announced that the Z Wave specification would become a ratified, multi source wireless standard. It includes the ITU. G9959 PHY/MAC radio specification, the application layer, the network layer, and the host device communication protocol. Instead of being a single source specification, it will become a multi source, wireless smart home standard developed by collective working group members of the Z Wave Alliance. The Z Wave Alliance would become a standards development organization (SDO), while continuing to manage the certification program. In August 2020, the Z Wave Alliance officially became incorporated as an independent nonprofit standards development organization, with seven founding members under its new SDO structure: Alarm. com, Assa Abloy, Leedarson, Ring, Silicon Labs, StratIS, and Qolsys. Under the SDO, there are new membership levels, workgroups, and committees, including technical working groups specific to features, and certification, security, and marketing groups.

Z Wave is designed to provide reliable, low latency transmission of small data packets at data rates up to 100 kbit/s, and is suitable for control and sensor applications, and with message ability to hop up to four times between nodes, it gives enough coverage for most residential houses. Modulation is frequency shift keying (FSK) with Manchester encoding, and other supported modulations schemes include GFSK and DSSS OQPSK. Z Wave uses the Part 15 unlicensed industrial, scientific, and medical (ISM) band, operating on varying frequencies globally. For instance, in Europe it operates at the 868 869 MHz band while in North America the band varies from 908 916 MHz when Z Wave is operating as a mesh network and 912 920 MHz when Z Wave is operating with a star topology in Z Wave LR mode. Frequency in MHzUsed in865.2India868.4China, South Africa868.4, 869.85Armenia, Bahrain, CEPT Countries (Europe and other countries in region), Egypt, French Guiana, Georgia, Iraq, Jordan, Kazakhstan, Kuwait, Lebanon, Libya, Nigeria, Oman, Philippines, Qatar, Saudi Arabia, South Africa, Turkmenistan, UAE, United Kingdom, Uzbekistan, Yemen869Russia908.4, 916Argentina, the Bahamas, Barbados, Bermuda, Bolivia, British Virgin Islands, Canada, Cayman Islands, Colombia, Guatemala, Haiti, Honduras, Jamaica, Maldives, Mauritius, Mexico, Moldova, Morocco, Nicaragua, Panama, St Kitts & Nevis, Suriname, Trinidad & Tobago, Turks & Caicos Islands, Uruguay, USA916Israel919.8, 921.4Australia, Brazil, Chile, Dominican Republic, Ecuador, El Salvador, Indonesia, Malaysia, New Zealand, Paraguay, Peru, Uruguay, Venezuela, Vietnam920.9, 921.7, 923.1Macau, Singapore, South Korea, Taiwan, Thailand922.5, 923.9, 926.3Costa Rica, Japan

Traditional hub and spoke networks include one central hub or access point to which all devices are connected, such as a wireless device connecting to a router. Z Wave devices create a mesh network, where devices can communicate with each other in addition to the central hub. Advantages to a mesh network include greater range and compatibility, and a stronger network. Z Wave LR devices operate on a star network topology that features the hub at a central point and then establishes a direct connection to each device, rather than sending signals from node to node until the intended destination is met, as in a mesh network. The key difference between a star network and a mesh network is the direct hub to device connection. Both Z Wave LR and traditional Z Wave nodes can coexist within the same network. Additional devices can be added at any time, as can secondary controllers, including traditional hand held controllers, key fob controllers, wall switch controllers and PC applications designed for management and control of a Z Wave network. A Z Wave network can consist of up to 232 devices, or up to 4,000 nodes on a single smart home network with Z Wave LR. Both allow the option of bridging networks if more devices are required. The Z Wave chip is optimized for battery powered devices, and most of the time remains in a power saving mode to consume less energy, waking up only to perform its function. In December 2019, Silicon Labs announced that it would release the Z Wave specification as an open wireless standard for development to be certified by the Z Wave Alliance. On November 17, 2016, the Z Wave Alliance announced stronger security standards for devices receiving Z Wave Certification as of April 2, 2017. Known as Security 2 (or S2), it provides advanced security for smart home devices, gateways and hubs. It shores up encryption standards for transmissions between nodes, and mandates new pairing procedures for each device, with unique PIN or QR codes on each device. The new layer of authentication is intended to prevent hackers from taking control of unsecured or poorly secured devices. According to the Z Wave Alliance, the new security standard is the most advanced security available on the market for smart home devices and controllers, gateways and hubs. The 800 series chip, released in late 2021, continues to support standard S2 security capabilities, as well as Silicon Labs Secure Vault technology, enabling wireless devices with PSA Certification Level 3 security. In 2022, researchers published several vulnerabilities in the Z Wave chipsets up to the 700 series, based on an open source protocol specific fuzzer. As a result, depending on the chipset and device, an attacker within Z Wave radio range can deny service, cause devices to crash, deplete batteries, intercept, observe, and replay traffic, and control vulnerable devices. The related CVEs (CVE 2020 9057, CVE 2020 9058, CVE 2020 9059, CVE 2020 9060, CVE 2020 9061, CVE 2020 10137) were published by CERT. Z Wave devices with 100, 200, 300 series chipsets cannot be updated to fix the vulnerabilities. For devices with 500 and 700 chipset series those vulnerabilities could be mitigated through firmware updates.

The chip for Z Wave nodes is the ZW0500, built around an Intel MCS 51 microcontroller with an internal system clock of 32 MHz. The RF part of the chip contains an GisFSK transceiver for a software selectable frequency. With a power supply of 2.2 3.6 volts, it consumes 23mA in transmit mode. At the Consumer Electronics Show on January 8, 2018, Sigma Designs introduced its Z Wave 700 platform. The 700 series chip was released in 2019. Z Wave LR is an extra 100 kb/s DSSS OQPSK modulation addition to the Z Wave protocol. The modulation is treated as a fourth channel, allowing gateways to add LR nodes to the existing Z Wave channel scanning. Z Wave LR also increases scalability on a single smart home network by up to 4,000 nodes, a 20x increase compared to Z Wave. The Z Wave MAC/PHY is globally standardized by the International Telecommunication Union as ITU 9959 radio, and the Z Wave Interoperability, Security (S2), Middleware and Z Wave over IP specifications were all released into the public domain in 2016, and Z Wave has become a fully ratified open source protocol for development. As of November 17, 2022 OpenZWave is no longer being actively maintained. Matter, brought forth by the Connectivity Standards Alliance, and founded on December 19, 2019, aims to unify device communication so that connected devices will work together, across both wireless technologies and smart home ecosystems. Z Wave networks have IP at the gateway level, enabling cloud connectivity to Matter. They can also work together at the local network level.