The Echo Service

What is the Echo Service?

The Torus Echo Service is a lightweight connectivity test running on the mesh at 10.254.100.102. If you can reach it, you are connected to the Torus.

It serves three purposes:

• Reachability check — confirms your WireGuard tunnel is up and routing correctly
• Latency measurement — measures round-trip time between your device and the London hub
• Interactive echo — a telnet service that reflects everything you type, useful for verifying bidirectional data flow

How to Use It

Web Browser

Open http://10.254.100.102 in your browser. You should see a dark-themed page with a pulsing green ring and the text “Connected to Torus”.

The page displays:

Ping Test

From any terminal on the Torus:

ping 10.254.100.102

Expected output for a London-connected user:

PING 10.254.100.102 (10.254.100.102): 56 data bytes
64 bytes from 10.254.100.102: icmp_seq=0 ttl=64 time=12.3 ms

Telnet Echo

The telnet service on port 23 echoes back everything you type — a classic connectivity test that confirms bidirectional data flow through the tunnel:

telnet 10.254.100.102

You will see a welcome banner with your tunnel IP address. Type anything and it will be reflected back to you. To exit, press Ctrl+] then type quit.

This is particularly useful for testing from retro or legacy systems that may not have a web browser or curl available.

API Endpoint

The echo service exposes a JSON endpoint at /ping:

curl http://10.254.100.102/ping

Response:

{"status":"ok","remoteIp":"10.254.100.109","rtt":"0.01","node":"10.254.100.102","hub":"eu-west-2"}

Expected Latency

Your measured latency depends on your physical distance from the London hub:

Troubleshooting

If the echo service is unreachable, see the Connection Issues page in this book for a step-by-step diagnostic guide.