ns-3 TCP: small keepalive packets don't update rtt estimation

[Richard Sailer]

Hi,

I implemented keepalive probes on application on top of tcp to keep the rtt estimations of TCP up to date even if there is no traffic for some time.

They snd small packets (a olsr header) every 20 ms. However tracing shows they don't actually change the tcp socket's rtt estimation.

Even if I change the delayed ack timeout to a small value. And the probes are sent and receive as I can see in wireshark.

Any ideas why that could be?

Thank you,
-- Richard