The Shift to TCP: How Matter 1.5 Evolved to Support Vision and Grid Intelligence

Since its launch in 2022, the Matter connectivity standard has cemented its role as the unifying standard for IoT interoperability, ensuring devices work together across Thread, Wi-Fi, and Ethernet regardless of brand differences. Architected to solve smart-home fragmentation, the protocol now fosters intuitive consumer experiences and unlocks new commercial and industrial applications.

However, connecting a diverse hardware spectrum — from low-power sensors to high-bandwidth streaming devices — requires constant evolution. To sustain this expanding ecosystem, the protocol must continuously innovate through regular updates that enhance stability and security.

The latest milestone in this evolution is Matter 1.5, released by the Connectivity Standards Alliance in November 2025. Moving beyond the command-and-control focus of earlier versions, Matter 1.5 expands the standard to handle data-intensive applications and sophisticated edge behaviors.

This release supports high-definition video for smart cameras and introduces grid-aware energy management. It also significantly advances mechanical control, moving from generic open/close commands to precise state management for complex access and shading systems, including doors, windows, shades, gates, and garage doors.

Matter’s Trajectory: Scaling the Stack

Achieving version 1.5's high-throughput capabilities required a systematic evolution of the technical foundation. Each iteration of Matter has tackled specific engineering hurdles, enabling the ecosystem to scale from simple sensors to sophisticated appliances:

• Matter 1.0 (the foundation): Established the IP-based transport layer, decoupling the application from the physical radio to enable interoperability across Thread, Wi-Fi, and Ethernet for essential categories like lighting and HVAC.
• Matter 1.1 (optimization): Optimized power management for intermittently connected devices (ICDs), refining polling intervals to ensure robust connectivity for battery-operated hardware such as contact sensors and door locks.
• Matter 1.2 (new domains): Moved beyond binary states to support hierarchical endpoints and semantic tags, enabling complex appliances like refrigerators and robotic vacuums.
• Matter 1.3 (metering and management): Implemented data structures for precise resource monitoring, introducing support for electric-vehicle supply equipment (EVSE) and water management.
• Matter 1.4 (infrastructure hardening): Addressed network topology challenges by integrating Thread 1.4 features, enabling grid-aware infrastructure like heat pumps and solar panels.
• Matter 1.5 (high-throughput transport): Unlocks high-bandwidth applications via Transmission Control Protocol (TCP) — a reliable, connection-oriented transport layer. This update manages the heavy payloads required for rich media streams and firmware transmission.

The Shift to TCP: Handling Heavy Payloads

The integration of TCP represents Matter 1.5’s most significant architectural upgrade. While earlier versions relied on the User Datagram Protocol (UDP) paired with the Message Reliability Protocol (MRP) to maximize battery efficiency for short sensor bursts, this approach struggles with continuous data streams.

Matter 1.5 leverages TCP to bridge this gap, supporting data-intensive tasks driven by two primary use cases:

1. High-definition media: Smart cameras require a transport layer that eliminates the jitter and packet loss inherent in connectionless protocols to ensure secure interoperability.
2. Over-the-air firmware updates: As firmware complexity grows, TCP ensures large binary blobs transfer reliably across the mesh, minimizing corruption risks.

For developers, the stack now intelligently distinguishes between traffic types — routing keep-alive signals via low-overhead paths while reserving TCP connections for heavy lifting.

Standardizing Vision: The Camera Challenge

Smart cameras have historically been the IoT market's most fragmented sector, constrained by unique bandwidth and security complexities. Matter 1.5 unifies this landscape by leveraging TCP to standardize cameras as a supported device type, enabling live audio and video streaming from any camera to any Matter-compliant interface.

The result allows users to unify disparate brands. For example, a smart doorbell from one manufacturer may be paired with security cameras from another within a single control system. Matter 1.5 replaces unreliable third-party workarounds with robust, native versatility.

Matter standardizes the connectivity layer without limiting intelligence. By remaining agnostic regarding AI detection logic (like face or package recognition), the protocol enables manufacturers to innovate with advanced analytics while relying on distinct clusters to govern the device's core mechanics:

• WebRTC integration: Leverages standard real-time protocols to enable secure, low-latency live streaming and two-way audio.
• Electromechanical control: Unifies commands for pan, tilt, and zoom (PTZ), allowing a single interface to manipulate optics across disparate hardware.
• Flexible storage: Defines attributes for both event-based local recording and cloud offloading, ensuring interoperability regardless of the specific storage topology.

Grid-Interactive Energy Management

Matter 1.5 upgrades the smart home from a passive power consumer to an active grid participant. It implements a sophisticated data model that lets devices subscribe to and publish complex energy attributes:

• Dynamic pricing and tariffs: The new Electrical Energy Tariff device type enables endpoints to ingest real-time pricing and time-of-use (TOU) data. High-load appliances, like washing machines or pool pumps, can autonomously shift operation to off-peak windows without cloud-side intervention.
• Carbon-aware operation: With a dedicated attribute for grid carbon intensity, devices are able to optimize run times based on local grid cleanliness, automatically prioritizing renewable energy usage.
• Bidirectional power flow: The model targets EVSE and solar inverters, standardizing control logic for vehicle-to-grid (V2G) applications. This transforms an EV charger into a regulated energy resource capable of discharging based on standardized grid signals.

Extending the Perimeter: Closures and Soil Sensors

Matter 1.5 sharpens control logic via the updated closures cluster. Distinguishing between device types that previously relied on generic commands, this update delivers precise position control for hardware ranging from garage doors to window shades.

The protocol also extends beyond physical walls with support for soil sensors. By standardizing moisture and temperature measurements, Matter 1.5 enables closed-loop irrigation systems where controllers poll sensors to optimize water usage based on real-time environmental data rather than static timers.

Streamlining Complex Development

Implementing high-bandwidth features like TCP and video clusters increases memory footprint and processing overhead on embedded processors.

Deploying Matter 1.5 requires development environments capable of deep-packet debugging and real-time energy profiling. Silicon Labs’ Simplicity Studio 6 addresses this challenge, pairing an updated Matter SDK with VS Code integration to streamline the creation of these data-intensive device types. Matter 1.5 proves the protocol is a scalable platform meeting high-bandwidth, high-intelligence demands, not just a connectivity standard.