Collect network operation data with logstash in Windows

I am trying to get network operation data from my localhost. I know packetbeat can do some of the jobs. However, I would like to collect data with logstash but my configuration didn't output anything. Is there anyone who can give me some suggestions?

        port => 9995
        codec => netflow{
            versions => [5]
        index => "logstash-%{+YYYY.MM.dd}"
        hosts => "localhost"

Can anyone help me with that? And I have get some confusion here:

what will be the difference in using netflow input or udp input?
What port should I listen to with udp input?
Thanks in advance.

Are you putting anything into the UDP input?