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 ~~two~~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:

Field	Description
Status	Shows `reachable` if you can communicate with the echo node
Your IP	Your WireGuard tunnel IP address (e.g. `10.254.100.109`)
Echo node	The echo service’s address: `10.254.100.102`
Hub	The hub hosting the echo service (London, eu-west-2)
Latency	Measured round-trip time (average of 4 samples)
Telnet	Address for the interactive echo service

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:

Location	Expected RTT
London / UK	5–15 ms
Continental Europe	20–40 ms
US East Coast	70–90 ms
Middle East (Dubai)	100–130 ms
US West Coast	130–160 ms
Asia Pacific	150–250 ms

Troubleshooting

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