Time sensitive Networking. This is the name of the IEEE 802.1 Task Group responsible for standards at Data Link Layer. This group provides the specifications that will allow time-synchronized, low latency, streaming services through IEEE 802 networks.
TSN is unique in that its streams are delivered with guaranteed bandwidth and deterministic latency. There are many features involved in the multiple standards currently under development. Some of the most relevant features and associated standards are:
- Synchronization: Synchronization is based on the IEEE 1588-2008 protocol. A specific profile is defined in IEEE 802.1AS.
- Prevention: TSN supports the concept of priority. A higher priority frame can interrupt the transmission of the lower priority frame to reduce the latency of time-sensitive streams (IEEE 802.1Qbu and IEEE 802.3br).
- Traffic Transformer: To achieve the lowest possible latency in engineered networks, Time Aware Shaper functionality is introduced in TSN. This works with applications where time-critical data is sent at periodic intervals and is based on adding timing gates to each queue on a port.
- Redundancy: High availability in TSN can be achieved by adding frame replication and dropout as defined in IEEE 802.1CB. Similar to that defined for HSR, frames include a sequence number and are replicated. Each copy is sent over a different network route.
- TSN is evolving and targeting different sectors such as Automotive, Industrial, Broadcasting, Defense and Aerospace. This flexibility can be achieved through reconfigurable logic (FPGA), HDL IPs and embedded software.