SmartMesh Technology

SmartMesh IP Functional Overview - Diagram 1SmartMesh® embedded wireless sensor networks deliver >99.999% data reliability and >10 year battery life, making it practical to deploy wireless sensor networks in the most challenging environments:

  • Tough RF Environments, having extensive metal and concrete, including industrial plants, data centers, commercial building monitoring, bridges, tunnels
  • Large Area Networks, such as street parking applications, smart street lighting networks spanning multiple city blocks, commercial irrigation
  • Dense Deployments, where thousands of nodes operate within radio range of each other, for instance data centers, utility scale solar farms
  • Networks on Moving Vehicles, including rail cars, cargo containers, semi-trucks or aircraft
  • Long, Extended Networks, including pipelines, mines, tunnels, bridges, fence line and smart street lighting
  • Remote Monitoring, where all nodes must be powered by battery or energy-harvesting, such as oil fields, agriculture, or environmental monitoring

A SmartMesh network consists of a highly scalable self-forming multi-hop, mesh of nodes, known as motes, which collect and relay data, and a network manager that monitors and manages network performance and security, and exchanges data with a host application.

SmartMesh motes and managers are complete wireless sensor network solutions. SmartMesh combines a time-synchronized, channel-hopping link layer with hardware based on Analog Devices’ Eterna® system-on-chip technology for a complete wireless networking solution with:

  • >99.999% Data Reliability, in the most challenging RF environments
  • >10 Year Battery Life, place sensors anywhere with lowest cost
  • Encryption, Authentication and Message Integrity Checks, secured network
  • Complete Wireless Mesh Solution, no network stack development required
LTC5800 Eterna

Ultra Low Power IEEE 802.15.4E System-on-Chip Platform

At the heart of SmartMesh motes and network managers is the Eterna IEEE 802.15.4e system-on-chip (SoC), featuring Analog Devices’ highly integrated, low power 2.4GHz radio design, plus an ARM Cortex-M3 32-bit microprocessor running SmartMesh networking software.

SmartMesh Networking

Time Synchronized, Channel Hopping Communications

SmartMesh networks communicate using a Time Synchronized Channel Hopping (TSCH) link layer, a technique pioneered by Analog Devices’ SmartMesh team and a foundational building block of wireless mesh networking standards, such as WirelessHART (IEC62591) and IEEE 802.15.4e. In a TSCH network, all motes in the network are synchronized to within a few microseconds. Network communication is organized into time slots, which enables low power packet exchange, pair-wise channel hopping and full path diversity.

Low Power Packet Exchange

The use of TSCH allows SmartMesh devices to sleep at ultralow power between scheduled communications, typically resulting in a duty cycle of < 1%. The network manager utilizes TSCH to ensure:

  • Motes know precisely when to talk, listen or sleep
  • No packets collide on the network
  • Ultralow power consumption at every node–routing nodes typically consume <50µA

Pair-Wise Channel Hopping

Time synchronization enables channel-hopping on every transmitter-receiver pair for frequency diversity. With a SmartMesh network:

  • Every packet exchange channel-hops to avoid inevitable RF interference
  • Multiple transmissions can occur simultaneously, increasing network bandwidth
  • Networks may be dense and scale without creating debilitating RF self-interference

Full Path and Frequency Diversity

Each device has redundant paths to overcome communications interruption due to interference, physical obstruction or multipath fading. If a packet transmission fails on one path, a mote will automatically retry on the next available path and a different RF channel. Unlike other mesh technologies, no power and time consuming path rediscovery is required.

SmartMesh Full Path and Frequency Diversity
Path and Frequency Diversity- if communication fails on the green arrow, node D retries on the red arrow using another channel.

Dynamic Network Optimization

A SmartMesh network always maintains a profile of the RF environment surrounding the entire network with automatic site surveys – each mote tracks relevant performance statistics and periodically sends these statistics to the manager in packets called health reports. The network manager uses this data to proactively optimize network performance to:

  • Maintain redundant pathways between motes in changing RF conditions
  • Lower system latency by adjusting the routing between motes
  • Reduce traffic retries by optimizing for paths with better RF performance
  • Reduce overall power consumption

Secure Mesh with 128 Bit Encryption

SmartMesh networks are among the most secure mesh networks available. All traffic in a SmartMesh network is protected by end-to-end encryption, message integrity checking, and device authentication. Additionally, the SmartMesh network manager contains applications that enable the secure joining of the network, key establishment, and key exchange. These security features provide:

Feature Benefit
Device Authentication Choose from three increasingly strong levels of device authentication
Encryption 128 bit AES-based encryption with multiple keys ensures privacy and confidentiality of the data
Message integrity check (MIC) Data transmitted is protected by message authentication codes to ensure that it has not been tampered with
Synchronized key changeovers The entire network changes over to a new encryption key automatically
Customized key rotation The customer decides how often the network should change keys, trading off extra security with additional network traffic

Standards and Industry Alliances

Analog Devices is committed to standards-based Wireless Sensor Networks and participates in a variety of standards organizations and alliances to promote the development and use of standards-based WSN. We support IEEE, IETF, IEC, and WirelessHART.

Standards and Industry Alliances