Siffle

Siffle is a CLI tool measuring network latency over UDP and TCP. It runs a server that echoes all UDP datagrams and TCP streams back to the source, allowing the client to measure round-trip latency.

While originally developed to test Siffleux TCP/UDP ingresses and egresses, it can measure latency across any network.

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How to Use

siffle is a single binary operates using a client-server model. Launch the echo server and then execute the client to test UDP or TCP latency.

1. Start the Echo Server

Run the server to echo incoming UDP datagrams and TCP streams.

# Listen on all interfaces (0.0.0.0) on default port 5678
siffle server

# Bind to a specific IP address and port
siffle server --ip 127.0.0.1 --port 8080

2. Run Latency Tests

Measure UDP Latency

# Run a 30 seconds UDP test with default settings (port 5678, 1000 mps)
siffle udp --server 127.0.0.1

# Run a 60 seconds UDP test sending ~5000 messages/sec on port 8080
siffle udp -s 127.0.0.1 -p 8080 -t 60 --mps 5000

Measure TCP Latency

# Run a 30 seconds TCP test with default settings (port 5678, 1000 mps)
siffle tcp --server 127.0.0.1

# Run a 15 seconds TCP test sending ~2000 messages/sec on port 8000
siffle tcp -s 127.0.0.1 -p 8000 -t 15 --mps 2000

CLI Reference

siffle server

Start the TCP and UDP echo servers.

Option	Short	Description	Default
--ip <IP>	-i	IP address the TCP and UDP echo servers will listen on.	0.0.0.0
--port <PORT>	-p	Port the TCP and UDP echo servers will listen on.	5678

siffle udp

Start testing latency over UDP.

Option	Short	Description	Default
--server <SERVER>	-s	[Required] IP address or hostname of the echo server.
--port <PORT>	-p	Port of the echo server.	5678
--duration <SECONDS>	-t	Duration in seconds for the test.	30
--mps <COUNT>		Target messages per second to send (approximate).	1000

siffle tcp

Start testing latency over TCP.

Option	Short	Description	Default
--server <SERVER>	-s	[Required] IP address or hostname of the echo server.
--port <PORT>	-p	Port of the echo server.	5678
--duration <SECONDS>	-t	Duration in seconds for the test.	30
--mps <COUNT>		Target messages per second to send (approximate).	1000