In this case yahoo chat messages are also transmitted as packets.
On the net you can find yahoo sniffer which sniffs packets to capture yahoo chat packets.
Now the question is… If you have sniffer running on your PC, sniffer can read only those packets that are coming to your system i.e., only your buddy’s messages. then how come you can get your neighbor’s chat messages?
Now the question is… If you have sniffer running on your PC, sniffer can read only those packets that are coming to your system i.e., only your buddy’s messages. then how come you can get your neighbor’s chat messages?
he answer lies here…. the type of hardware device used to connect multiple PC’s (your, neighbors) by your internet provider.
Switch uses a mapping table that contain entries of IP address and Lan card MAC address. As packet arrives, switch decides to which PC the packets need to be directed to by looking into Mapping table. There are few sniffers on the web that can modify the mapping table in the switch device to direct all the packets to a hacker PC who has installed this sniffer.
Sniffers that modifies mapping address in the switch are detectable and can be caught.
Sniffers that only rely on Hub can’t be caught or detected because, they are just sitting on the hackers PC.
Lets take an example. A, B and C are using X ISP and all are connected to the internet by the hub.
What a hub does is that it gets packets from outside world and sends them to all the connected devices without checking the destination IP address embedded in the packet. A, B and C will receive the packets and the LAN card will check the destination IP address to decide whether to discard the packet or not. Lets say, A is chatting with his friend. A,B and C gets A’s friend message but A’s PC accepts the packet, decodes it and shows up the message. B’s and C’s PC will discard it.
What sniffer does is, it sits at the gate of the PC that is on the LAN Card, captures all packets (in this case yahoo sniffer), if it detects yahoo packet, it will decode and show the message.
If B’s PC has installed yahoo sniffer, B can read A’s message and his friend’s message.
Switch device takes the packet check the destination IP address and sends it to only respective PC.
So, if you wanna know whether your network is connected via hub or switch, just run the sniffer and check it for 1 or 2 hours. If you see only your and your buddy’s message then a switch is used; if you see others messages as well then a hub is used( in which case you are in a danger as your messages are leaked).
There are two types of devices that can be used :
- Hub (Ethernet hub)
- Switch
Switch uses a mapping table that contain entries of IP address and Lan card MAC address. As packet arrives, switch decides to which PC the packets need to be directed to by looking into Mapping table. There are few sniffers on the web that can modify the mapping table in the switch device to direct all the packets to a hacker PC who has installed this sniffer.
Sniffers that modifies mapping address in the switch are detectable and can be caught.
Sniffers that only rely on Hub can’t be caught or detected because, they are just sitting on the hackers PC.
Lets take an example. A, B and C are using X ISP and all are connected to the internet by the hub.
What a hub does is that it gets packets from outside world and sends them to all the connected devices without checking the destination IP address embedded in the packet. A, B and C will receive the packets and the LAN card will check the destination IP address to decide whether to discard the packet or not. Lets say, A is chatting with his friend. A,B and C gets A’s friend message but A’s PC accepts the packet, decodes it and shows up the message. B’s and C’s PC will discard it.
What sniffer does is, it sits at the gate of the PC that is on the LAN Card, captures all packets (in this case yahoo sniffer), if it detects yahoo packet, it will decode and show the message.
If B’s PC has installed yahoo sniffer, B can read A’s message and his friend’s message.
Switch device takes the packet check the destination IP address and sends it to only respective PC.
So, if you wanna know whether your network is connected via hub or switch, just run the sniffer and check it for 1 or 2 hours. If you see only your and your buddy’s message then a switch is used; if you see others messages as well then a hub is used( in which case you are in a danger as your messages are leaked).
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