oui c'est l'equivalent d'un heartbeat.
Ca peut être fait coté serveur aussi avec ClientAliveInterval (voir "man sshd_config")
ClientAliveInterval
Sets a timeout interval in seconds after which if no data has
been received from the client, sshd(8) will send a message
through the encrypted channel to request a response from the
client. The default is 0, indicating that these messages will
not be sent to the client. This option applies to protocol verâ
sion 2 only.