I have this in my show int in a switch C3524, in the port that connect to the switch core:

5 minute input rate 149000 bits/sec, 28 packets/sec

5 minute output rate 35000 bits/sec, 17 packets/sec

116142 packets input, 71731977 bytes

Received 9904 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 3193 multicast

and I see that I have at least 5 multicast by second.

Where does it mean?

where does it came from?

Can I know how is generating this kind of traffic?

Regards and thanks