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mikehende
08-24-2006, 10:45 AM
In Mike Meyer's Book, it says that an NIC "waits" for an empty line before sending a "frame" to the Network, I know this is regarding using a "Hub" network, I am using a Router, I have just tried both copying a folder from pc A to pc B on my Network and vice versa at the same time and it works, what I would like to know is, if I were using a Hub instead of a Router, would I have been able to copy folders e.t.c to and from two pc's at the same time as I can do with my network or would it have had to wait until pc A had finished copying from pc B then pc B would start copying from pc A?

golfmore
08-24-2006, 12:11 PM
Doesn't a hub get the packets to all ports, even though it's meant to go to just one? Or am I confused? I thought a switch was a semi intelligent hub.

mikehende
08-24-2006, 12:47 PM
Doesn't a hub get the packets to all ports, even though it's meant to go to just one?

Yes, it does, according to my reading and the port that it's destined for will allow it, the others will reject it.

One answer I found for my question is that yes, the NIC does wait until a line is clear before sending or jumps in between the transmission but this all happens so quickly that we can't detect when it happens.

TonyDi
08-24-2006, 07:27 PM
It's all done in TCP (Transmission Control Protocol). When asked to send information, the network card senses the network to see if anyone else is transmitting. When the line is quiet, it tries to send the requested data. Sometimes more than one node will sense a quiet network and send data. This results in a collision and nothing makes it through. This is also sensed by TCP and will try to send the data again.
- tony