MDT

Terms

ST — Streaming Telemetry

MDT — Model Driven Telemetry

• Can be ordinary TCP
• Can also use gRPC, to add TLS

TCP dial-in

• Collector establishes a connection
• Then subscribes

sequenceDiagram
    participant C as Collector
    participant R as Router

    C->>R: SYN
    R->>C: SYN-ACK
    C->>R: ACK
    R->>C: Telemetry data

TCP dial-out

• Telemetry is pushed to the collector
• As soon as it changes (low latency)
• When in changes (low throughput)

sequenceDiagram
    participant C as Collector
    participant R as Router

    R->>C: SYN
    C->>R: SYN-ACK
    R->>C: ACK
    R->>C: Telemetry data

References

Cisco - Whitepaper - Model Driven Telemetry

Cisco Live - gRPC, gNMI, gNOI … Oh My! - Jeremy Cohoe - BRKDEV-2017

NANOG73 - SNMP is Dead - Carl Lebsack, Rob Shakir

XRdocs - Model-Driven Telemetry: Dial-In or Dial-Out ? | Telemetry