[gabebillings]

I'm getting ready to move a bunch of stuff between some existing computers, and I came up with what seems like a simple question I can't answer.

Consider the following network: Two desktop PCs with wired connections to a gigabit switch, and a laptop with a wireless-G connection to a router hooked into the aforementioned switch. If I were to get on one of the desktops and copy a file from a shared drive on the other desktop, it would be traveling over the 1,000 Mbps wired connection.

So what happens if I'm using the laptop, go into Windows Explorer and then do the same operation, copying a file from a share drive on one desktop over to the other desktop?

Are the computers smart enough to know where the file is coming from and going to and then take the fastest route between them? Or since the request originated on the laptop will it transfer the file to the router, the to the laptop via wireless, then back to the router, then along to the other desktop?

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Well they can only go through the router so realistically there is no straight line as such, its the only way to go. The router does not hold any data, it just passes it through.

[Neil Jones]

Well they can only go through the router so realistically there is no straight line as such, its the only way to go. The router does not hold any data, it just passes it through.

[gabebillings]

Yes, but the question is does that data need to pass through the laptop, since that's where the request originated?

[hfcg]

Hello,
I do not understand what your question is.
When you transfer Data from the laptp, to the desktop(s);

• The data will be transmited through the router.
• Through the switch.
• And to the desktop(s).

Source/path/destination.
The laptop is the source, the router and switch are the path, and the desktop is the destination.
(It would be faster to hardwire the laptop to the router, than use it wireless.)

Edited by hfcg, 22 March 2008 - 06:29 PM.

[gabebillings]

Yes. Apparently I'm not explaining myself well enough. But now there are visual aids!

So I'm sitting upstairs, working on the laptop. I open My Computer and see both of the following share drives. They exist on two different desktop computers; Aquos and Titan. The laptop is connected to my Linksys router via an 802.11g connection. The two desktops are actually plugged into the router right now, but for the sake of argument let's assume it's a gigabit switch (which will be here in a couple of days) that's connected to said router. So here's My Computer:



Now, I open the share drive on Aquos, choose a file and select the 'Move this file' option, and choose the share drive on Titan as the location I want it to go. So we've got this:



So, as you can see, the data is starting on one desktop and ending on the other. I'm using the laptop, however, to inititate this move, even though the data is neither coming from nor going to it. So I don't know if this is a question about how Windows works, or if it's all about the routing, or what. Does this make more sense? I don't know how else to explain it. So what I'm asking is, is this file that is being moved going through the laptop as it travels from one computer to the other, or is it moving straight from one to the other? (Yes, I understand that either way it's moving through the router, I just want to know if the laptop is part of the equation.)

[gabebillings]

Actually, this leads me to yet one further question. As I said, the desktops in question are currently plugged into the router, which is a Linksys WRT54G. This has a 100 Mbps switch in it. I was under the impression that I could speed up the wired portions of the network by adding a gigabit switch and simply plugging that into the current router, which I understand will work.

But doesn't that mean that the short jumper that connects the router to the new switch is only running at 100 Mbps? So even though it's a gigabit switch, with gigabit NICS at either end, the short hop to the router is the proverbial 'weak link in the chain'?

I don't understand enough about exactly how data is moving around the network.

The router assigns the various devices IP addresses, right? So once computer A and B are established as 192.168.1.100 and .101, does the switch know which is which and can move data through by itself? Or do those packets still need to go into the switch, over to the router, back to the switch, and then on to destination?

I should probably go read a book on networking so I wouldn't have to bother you guys.

[hfcg]

If you use a gigabyte switch to connect two GB NICS, you will get the benifit of the faster data transfer between the two NICS.
The router that connects to the switch, and laptop, will be slower.

[gabebillings]

Great. As as to the original question, above? Data transfer initiated by, but not to or from the laptop? What's the verdict on that?

[gabebillings]

Ok, so in the excitement of trying to explain my question, I forgot about just trying it. I made sure the kids were mesmerized by the TV, then ran downstairs and tried it there, then came back up and gave it a shot at the laptop.

File: 206,000 KB

Initiated on a desktop
Elapsed time: 20 seconds
10300 KBps / 10.05 MBps

Initiated on the laptop
Elapsed time: 178 seconds
1157 KBps / 1.13 MBps

So as far as I can tell, that file does in fact travel from one desktop to the other THROUGH the laptop, which isn't very efficient. So when I start to move video files around, I'll have to do it from down there. Or use remote access.

[peterm]

File wont go through lap top
To test send data as last and shut laptop down while file is transfering
does file finish or does it get interupted?
If finishes then not via laptop if not then via laptop.
My money is on NOT via laptop

[gabebillings]

It would seem that in looking at my little test above that the file does in fact go through the laptop. But to be sure, I went ahead and tried it your way to. I set up the file copy in the same manner, and then waited until it had started and then simply flipped the wireless switch on the side of the laptop, severing the connection.

Sure enough, the transfer stopped immediately. Windows popped up an error message saying it couldn't complete the transfer.

[PARIAH]

HOw bizarre. I would think that snce it knows that it goes from A to B it shouldn't matter that C told it to happen...

Might it be interrupted not because the date goes through the laptop,m but because the laptop is responsible for MONITORING the xfer? When the laptop is shut down, The proverbial watchman's not at work and all the laborers don't know what to do...

Could we test this by monitoring data flow itsel; by monitoring each node's bandwidth and network usage with the onbaord tools?

[peterm]

Very Interesting