Horrible LAN Speeds

[su root]

I know I've seen a few threads like this before (with no solid solutions to them)but... my LAN speeds are horrible.

2 x Win2k Pro SP3 boxes (P3 800 and P3 1gig)
Connected by an AOpen 10/100Mbits 5-port hub.
Also connected to the hub is my 10Mbits Cable modem.

Both machines are set to 100Mbits/half duplex.

From ComputerA, sending to computer B:
50 megs transferred in 20 minutes (aprox). -- estimated 37 minutes at the beginning

From ComputerB, sending to computer A: (same data)
50 megs transferred in 2 minutes (aprox). --estimated 10 minutes at the beginning.

One computer is running a D-Link 530tx, and the other one is running a Phoebe 10/100 NIC (Realtek) --could the realtek be the problem?.. i don't have another nic around..

I understand that on a 10/100 hubbed network, introducing a device like a 10Mbit cable modem will effectively slow all traffic down to 10Mbits, however, when I remove the cable modem, nothing speeds up. (that, and 10Mbits should yeild me 1.25Mbytes/second ideal throughput.

Hard disks are almost idle while transferring (no thrashing).. they're fully defragmented. There is network traffic and the occasional collision @ 100Mbits. Only protocol installed is TCP/IP. They're physically right beside eachother.. i havn't checked the cables though, don't got any extras around..

Oh yeah, they are both registry tweaked for cable internet:
tweak output
www.broadbandreports.com/1036902502]internet bandwidth[/url]

my RWIN is a bit high, could that be a problem?
also, they're both using ZoneAlarm, but I had this problem before I installed zonealarm.

anyone have any ideas?

 

[Kingslayer]

Ok. Yes it could be the cable modem, however when its unplugged it should take everything back to 100. But you may need to reboot the hub to get it set to 100. Try that and let me know how it goes.

 

[su root]

Well, lets see here:

Pre-test: slow, 30 minutes/50 megs
Test1, reboot hub, disconnect internet, use 192.168 static addys: fast: 20 seconds/50 megs
Test2: reconnect internet, internal ips: 20seconds/50 megs
Test3: external IPs (same setup as pre-test) 20 seconds/ 50 megs

conclusion:
hub needed reboot? -- havn't rebooted it for about a year..
computers needed network-reinitialization? -- booted 1 this morning, the other was up for 2 or 3 days..
could be the realtek -- it got re-inited when the hub was powered down
not cabling
not cable modem (although it could still be slowing it down, i'd need a larger test)

thx Kingslayer.. some times it's the dumbest things...

 

[Kingslayer]

I'm sorry, I meant disconnect the cable modem BEFORE you reboot the hub. Some hubs have firmware that will lock everything down to 10 meg if it sees a 10 meg connection. Take the 10 meg connection off and reboot the hub, and it clears that firmware and puts everything back to 100.

 

[su root]

that's what i did.. unplugged the cable modem, unplugged the hub, plugged the hub back in, and everything ran fast. then I reconnected the cable modem, and it still ran fast..

 

[64026402]

Yes, periodic slow downs may indicate the need to reset the hub.
I have to reset my hub and router every month or 2 because of slow down.

 

[Kingslayer]

I'm sorry su, I thought you were still having problems.

 

[su root]

it's curious about that.. my hub is the simplest hub there is... i got it a few years ago.. nothing special. Weird that that would be the problem..

 

[64026402]

Switches are pretty cheap as are routers.(sometimes the routers are cheaper)
You could gain from a switch. Routers add flexabilty.
Just a thought.

 

[DDR-PIII]

when stuff is run through a HUb it all will be set to 10.mbps weather the cable modem is there or not... just got a cross overcable it works better and you get 100/full duplex

 

[Kingslayer]

I would look into ditching the hub and getting a 5 port Linksys switch. They are cheap and auto-sensing and auto-switching. That means that what is 100 will run at 100 and what is 10 will run at 10. You wont have this problem ever again with it.

 

[su root]

Actually, that network is almost completely for internet access... when I am living there, i have my 8-port DLink switch with me, and replace it for the time while I'm there.

DDR-PIII:
when stuff is run through a HUb it all will be set to 10.mbps weather the cable modem is there or not... just got a cross overcable it works better and you get 100/full duplex

what do you mean by this?
it's a 10/100Mbit hub. Without the cable modem, everything should run at 100Mbits/half, and with the cable modem, the cable modem runs at 10Mbits/half, and the rest run at 100Mbits/half.. the throughput will only achieve 10Mbits with the cable modem plugged in (due to CSMA/CD, everyone has to hear everything), and should achieve 100Mbits throughput when the cable modem is not plugged in. If I use crossover cable, i would need (a) crossover cable and (b) another NIC for internet access, and (c) I would require one computer to be left on all the time. My current solution is better.

There is also a third computer on this network now, but it is only used via the internet (or if I'm standing at the console).

 

[DDR-PIII]

im not sure, its just with hubs everything works @ 10/full duplex "max"

 

[moorcito]

There are a ton of other factors to take into consideration when figuring Lan speeds because it doesn't just depend on the hub nor the nic. Take your hard drive for instance. What's the read/write and the seek time? You bus speed, memory, processor, etc. all affect you lan speeds, and not to mention when to consider network latency, protocol overhead, driver efficiency, and all kinds of other technical things get in the way. In general, expect transfer speeds of 40 to 80% of the maximum speed.

 

[su root]

im not sure, its just with hubs everything works @ 10/full duplex "max"

if that were true, then there would be no difference between a 10Mb hub and a 100Mbit hub. Currently there are several types:

10Mbit
10/100Mbit
100Mbit -rare, they only allow 100Mbit connectoins
10/100/1000Mbit -havn't heard of these, but they probably exist..

 

[Kingslayer]

Biggest thing you can do to increase your network bandwidth if your running XP is to turn that damn QoS service off in your network properties.

It really slows things down and isnt necessary on a LAN.

 

[su root]

I'm running 2k on everything right now.. don't have the time to bother gutting XP's bloat.

 

[alrox]

with half duplex connections you're going to get a slowdown as compared to if they were full duplex because of the collisions on ANY port. if you're downloading things on the internet for example, its going to make your pc<->pc file transfer backoff and wait to transmit again. on the 'slow' computer do a "netstat -e" and look for incrementing errors, and if your drivers allow you to look at the # of collisions, do that too.

If you get a lot of errors when only the 2 w2k pc's are plugged into the hub, then you may have a bad cable on the slow pc & try switching the ports that the pc's are plugged into as well. your hub must be a real piece of crap if it doesn't do full duplex connections, that switch upgrade will do you a lot of good.

I know I've seen a few threads like this before (with no solid solutions to them)but... my LAN speeds are horrible.

2 x Win2k Pro SP3 boxes (P3 800 and P3 1gig)
Connected by an AOpen 10/100Mbits 5-port hub.
Also connected to the hub is my 10Mbits Cable modem.

Both machines are set to 100Mbits/half duplex.

From ComputerA, sending to computer B:
50 megs transferred in 20 minutes (aprox). -- estimated 37 minutes at the beginning

From ComputerB, sending to computer A: (same data)
50 megs transferred in 2 minutes (aprox). --estimated 10 minutes at the beginning.

One computer is running a D-Link 530tx, and the other one is running a Phoebe 10/100 NIC (Realtek) --could the realtek be the problem?.. i don't have another nic around..

I understand that on a 10/100 hubbed network, introducing a device like a 10Mbit cable modem will effectively slow all traffic down to 10Mbits, however, when I remove the cable modem, nothing speeds up. (that, and 10Mbits should yeild me 1.25Mbytes/second ideal throughput.

Hard disks are almost idle while transferring (no thrashing).. they're fully defragmented. There is network traffic and the occasional collision @ 100Mbits. Only protocol installed is TCP/IP. They're physically right beside eachother.. i havn't checked the cables though, don't got any extras around..



anyone have any ideas?

 

[su root]

actually, my hub has a collision light, so I can see when it collides on 100 or on 10. there is the odd collision when transferring at high speed, but that's to be expected, as there is 4 devices on the network. The number of collisions is small, only once in a while.

 

[64026402]

actually, my hub has a collision light, so I can see when it collides on 100 or on 10. there is the odd collision when transferring at high speed, but that's to be expected, as there is 4 devices on the network. The number of collisions is small, only once in a while.

The collision light is not a very good indicator. At 100Mbits you wouldn't be able to see anything but the worst collisions.
A hub is inherently inefficient with more than 2 devices on the network. Switches are cheap nowdays. If you have a wish for a good reliable network, it would be a good upgrade.