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VLAN, separate broadcast domain ?
- Thread starter iriscisco
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Jimmyzz,
PC/workstation IS more than just a layer 1 device which generates bits (from layer 7 down to 1) like you've said. but what i am saying is, PC/workstation is just sending plain bits (across the medium)..not packets (unlike routers). am i wrong?
Microbyte
PC/workstation IS more than just a layer 1 device which generates bits (from layer 7 down to 1) like you've said. but what i am saying is, PC/workstation is just sending plain bits (across the medium)..not packets (unlike routers). am i wrong?
Microbyte
yes, that line of thinking is incorrect. If it's correct, then routers, layer 4 switches, industrial RS232 to ethernet devices all just send bits and not packets or frames. If you really want to split hairs, the output of the NIC are not bits but a series of voltage changes across the wire. It's up to the software/Firmware drive of the NIC to understand these changes of voltage actually mean something such as a 1 or 0. But dont mistake a 1 for a +5 vdc and the 0 as zero voltages. Thats not how differential circuits work. You can have 5 as the high, 2.5 as the low, 0 as error or noise, -2.5 as a low and -5 as a high. It's all a matter of programming.
This is why in the world of networking, PCs send packets.. routers send packets and switches send frames. Everyone has to have a common point of reference in order to communicate effectively.
MikeS
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"Take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots."
Sun Tzu
This is why in the world of networking, PCs send packets.. routers send packets and switches send frames. Everyone has to have a common point of reference in order to communicate effectively.
MikeS
Find me at
"Take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots."
Sun Tzu
wybnormal,
I just thought of this. how is this argument?
PC/Workstation doesn't have any knowledge of where to send the information except just dropping it onto a physical medium just like hubs do.
and doesn't hubs just floods all ports on every transmission because it doesn't have any address checking mechanism? (hub works on layer 1 right?)
unlike routers, pc doesn't know the logical address (ip) to its destination.
unlike switch, pc doesn't know the physical address (MAC) to its destination.
I just thought of this. how is this argument?
PC/Workstation doesn't have any knowledge of where to send the information except just dropping it onto a physical medium just like hubs do.
and doesn't hubs just floods all ports on every transmission because it doesn't have any address checking mechanism? (hub works on layer 1 right?)
unlike routers, pc doesn't know the logical address (ip) to its destination.
unlike switch, pc doesn't know the physical address (MAC) to its destination.
Last time I checked the PC does have to know the destination IP and MAC or it wouldn't bother to put it in the layer 3 packet or Layer 4 Frame (Encapsulation) in the first place. Therefore you would be sending your data to nowhere.
Layer 3: Provides "logical" addressing which router use for path determination. Without that your packet is homeless.
And for switching, the sending device needs the IP and MAC of the destination devices in which an ARP request comes into play.
SpudNuts(ITC), USN(Ret), CCNA, BSCI, BCRAN, CST
Layer 3: Provides "logical" addressing which router use for path determination. Without that your packet is homeless.
And for switching, the sending device needs the IP and MAC of the destination devices in which an ARP request comes into play.
SpudNuts(ITC), USN(Ret), CCNA, BSCI, BCRAN, CST
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