I am very much conscious about how to find node which is doing broadcast in LAN, when broadcast start my network speed very much slow, kindly have anybody solution, how I fix this.

Regards,

Try the following tools:

NetScan is a free utility from SoftPerfect that will scan your network and identify all of the nodes that are connected to it - PC's, printers, servers, switches, routers, etc.

WireShark is a free utility that allows you to perform packet level analysis and port scanning on your network. It can identify the specific devices that are flooding the network on specific ports.

Neither of these tools are the full answer if you have an old hub that is flooding your network with collisions. But if you have managed switches, you can logon to your switches and look at the Port Statistics and see which ports that are producing lots of errors. If this is not the case, then go to each old hub and disconnect it from the network and see if your network calms down. They will likely have an amber collision light on them as well to help identify problems.

If you find that an unsuspecting user has downloaded a virus or port scan attacking worm, I think that a flogging with a network patch cable is in order.