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SlickRCBD
04-16-08, 05:32 PM
I have two functional computers hooked up to a linksys router/switch
combination. One is a still functional older computer with a mere
10baseT ethernet card. The other has a 10/100 card. My older computer
has a large hard drive, but I no longer have a working CD burner. I'm
trying to do a backup of a large amount of data using the newer XP
machine via ethernet. My question is this, based on a comment that
somebody made to me about linksys switches.
If I'm connecting to the computer with the 10 megabit card, will my
switch slow down to 10 megabits for all connections? I'm concerned that
attempting to surf the 'net while I wait for the files to transfer will
slow down my transfer process. Given that I have a 100 megabit card and
router, it should be able to handle the traffic from the old computer at
the old computer's full speed without slowing down the internet, which
IIRC is only a 4 megabit connection. 10 + 4=14 < 100, even when
factoring in collisions. However, the switch slows down to 10 megabits,
I'd want to stick this operation overnight and have it done while I sleep.

News Reader
04-16-08, 06:46 PM
SlickRCBD wrote:
> I have two functional computers hooked up to a linksys router/switch
> combination. One is a still functional older computer with a mere
> 10baseT ethernet card. The other has a 10/100 card. My older computer
> has a large hard drive, but I no longer have a working CD burner. I'm
> trying to do a backup of a large amount of data using the newer XP
> machine via ethernet. My question is this, based on a comment that
> somebody made to me about linksys switches.
> If I'm connecting to the computer with the 10 megabit card, will my
> switch slow down to 10 megabits for all connections? I'm concerned that
> attempting to surf the 'net while I wait for the files to transfer will
> slow down my transfer process. Given that I have a 100 megabit card and
> router, it should be able to handle the traffic from the old computer at
> the old computer's full speed without slowing down the internet, which
> IIRC is only a 4 megabit connection. 10 + 4=14 < 100, even when
> factoring in collisions. However, the switch slows down to 10 megabits,
> I'd want to stick this operation overnight and have it done while I sleep.

The issue likely has less to do with the router/switch's capabilities
than the fact that the computer you are browsing the Internet with is
involved in a file transfer (CPU utilization, HD access, etc.).

Each switch port is its own collision domain. Traffic from one host will
not collide with traffic from another host. If you were using half
duplex settings on a host and the switch port it was connected too, you
could experience collisions between sending and receiving traffic on
that physical link, but that is normal and not worth worrying about. The
two will probably negotiate full duplex anyway.

The FastEthernet port of your new system and the FastEthernet port of
the switch it is connected to, can handle the combined throughput of the
file transfer and Internet activities without difficult.

The throughput of the transfer between the computers is limited by the
Ethernet card in the old system. The switch receives data at a higher
bit rate from the new system, will buffer it in memory, and forward it
to the old system at the lower bit rate. The TCP protocol will also
regulate the speed based on errors/retransmissions etc. The throughput
of your Internet activities is limited by the ISP connection.

The real issue is the resources of your new system, and whether they
will be challenged by the combined activities (file transfer and
Internet activity). Web browsing taxes your system less than streaming
media or FTP downloads etc.

Why not do a test transfer (~ 5min.) while using the Internet (in what
ever way you intend), and see what happens?

Best Regards,
News Reader

SlickRCBD
04-18-08, 01:37 AM
News Reader wrote:
> SlickRCBD wrote:
>
>> I have two functional computers hooked up to a linksys router/switch
>> combination. One is a still functional older computer with a mere
>> 10baseT ethernet card. The other has a 10/100 card. My older computer
>> has a large hard drive, but I no longer have a working CD burner. I'm
>> trying to do a backup of a large amount of data using the newer XP
>> machine via ethernet. My question is this, based on a comment that
>> somebody made to me about linksys switches.
>> If I'm connecting to the computer with the 10 megabit card, will my
>> switch slow down to 10 megabits for all connections? I'm concerned
>> that attempting to surf the 'net while I wait for the files to
>> transfer will slow down my transfer process. Given that I have a 100
>> megabit card and router, it should be able to handle the traffic from
>> the old computer at the old computer's full speed without slowing down
>> the internet, which IIRC is only a 4 megabit connection. 10 + 4=14 <
>> 100, even when factoring in collisions. However, the switch slows down
>> to 10 megabits, I'd want to stick this operation overnight and have it
>> done while I sleep.
>
>
> The issue likely has less to do with the router/switch's capabilities
> than the fact that the computer you are browsing the Internet with is
> involved in a file transfer (CPU utilization, HD access, etc.).
>
> Each switch port is its own collision domain. Traffic from one host will
> not collide with traffic from another host. If you were using half
> duplex settings on a host and the switch port it was connected too, you
> could experience collisions between sending and receiving traffic on
> that physical link, but that is normal and not worth worrying about. The
> two will probably negotiate full duplex anyway.
>
> The FastEthernet port of your new system and the FastEthernet port of
> the switch it is connected to, can handle the combined throughput of the
> file transfer and Internet activities without difficult.
>
> The throughput of the transfer between the computers is limited by the
> Ethernet card in the old system. The switch receives data at a higher
> bit rate from the new system, will buffer it in memory, and forward it
> to the old system at the lower bit rate. The TCP protocol will also
> regulate the speed based on errors/retransmissions etc. The throughput
> of your Internet activities is limited by the ISP connection.
>
> The real issue is the resources of your new system, and whether they
> will be challenged by the combined activities (file transfer and
> Internet activity). Web browsing taxes your system less than streaming
> media or FTP downloads etc.
>
> Why not do a test transfer (~ 5min.) while using the Internet (in what
> ever way you intend), and see what happens?
>
> Best Regards,
> News Reader
Well, I've decided that I'll just run it overnight. I'll probably do a
test or two once it gets going, but I didn't do the math very well on
just how long it's going to take to transfer all the files at
10megabits. The last time I had to do a backup on this computer via the
network I only had a the original 4gb drive in that computer and
10mb/sec didn't take that long relatively speaking. I did the math based
on 100 megabits, and am too used to the gigabit ethernet at work that I
forgot how slow 10 megabites was. Kinda funny to call it slow, since I
remember comparing the speed of the serial-based Appletalk connection
between the older Macs at school vs the brand new Macs with Ethernet and
thinking the 10baseT ethernet was REALLY fast. Then again, I thought the
1GB drive in the [then] new server they installed at high school was HUGE.

Ed in Calif
04-29-08, 07:51 PM
I don't think it should matter. On my linksys router
there are three lights for each port; Link, Col, and 100.

If I plug in a 10bT and a 100bT PC's the lights show the
correct speed.

So I think the answer is your network will not slow down
in you plug in a 10bT, but if you are doing a point to point
transfer that may be the bottle neck.

If you use the old coax daisy chain method it would slow
down that segment.

Ed


"SlickRCBD" <spamyourself@127.0.0.1> wrote in message
news:26OdnRCqWdiL45vVnZ2dnUVZ_g6dnZ2d@comcast.com...
> I have two functional computers hooked up to a linksys router/switch
> combination. One is a still functional older computer with a mere 10baseT
> ethernet card. The other has a 10/100 card. My older computer has a large
> hard drive, but I no longer have a working CD burner. I'm trying to do a
> backup of a large amount of data using the newer XP machine via ethernet.
> My question is this, based on a comment that somebody made to me about
> linksys switches.
> If I'm connecting to the computer with the 10 megabit card, will my switch
> slow down to 10 megabits for all connections? I'm concerned that
> attempting to surf the 'net while I wait for the files to transfer will
> slow down my transfer process. Given that I have a 100 megabit card and
> router, it should be able to handle the traffic from the old computer at
> the old computer's full speed without slowing down the internet, which
> IIRC is only a 4 megabit connection. 10 + 4=14 < 100, even when factoring
> in collisions. However, the switch slows down to 10 megabits, I'd want to
> stick this operation overnight and have it done while I sleep.