[syslog-ng] Disk based queuing with rsyslog?

Hi, I read that syslog-ng can be setup to use disk based with flow control with the client to prevent lost of logs. However I was just thinking, how does this mechanism works? Does the client have to be using syslog-ng? Will it work if the client is using rsyslog? Native appliance that purely support syslog? Yours Sincerely, Delon Lee