I can only answer your question in general terms, since I have not actually used the Wireshark packet sniffer. I have used other packet sniffers.

In general, packet sniffers are only useful for sniffing packets to or from the PC they are installed on. In most modern switched networks, traffic going to or from other PCs in the network is generally not seen by other PCs on the network, thus there is no way for a packet sniffer to detect it. This is because the router and switch on your network will route network traffic directly to the INTENDED devices without broadcasting it to every device on the network.

In order to monitor your brother’s PC you would either NEED a packet sniffer installed on his PC, or you would need a packet sniffer installed on the GATEWAY device, i.e., your router.

Alternatively, you could place your PC and your brother’s on a HUB–not a switch. A hub is “dumber” than a switch in that it repeats all traffic on all ports. However this is not ideal for speed and network collision ISSUES.

I can only answer your question in general terms, since I have not actually used the Wireshark packet sniffer. I have used other packet sniffers.

In general, packet sniffers are only useful for sniffing packets to or from the PC they are installed on. In most modern switched networks, traffic going to or from other PCs in the network is generally not seen by other PCs on the network, thus there is no way for a packet sniffer to detect it. This is because the router and switch on your network will route network traffic directly to the intended devices without broadcasting it to every device on the network.

In order to monitor your brother’s PC you would either need a packet sniffer installed on his PC, or you would need a packet sniffer installed on the gateway device, i.e., your router.

Alternatively, you could place your PC and your brother’s on a hub–not a switch. A hub is “dumber” than a switch in that it repeats all traffic on all ports. However this is not ideal for speed and network collision issues.