Large files transferred across my LAN are sometimes corrupted - why?

[Guest_imported]

I have an extremely simple LAN - 2 PC's connected by a 100Mpbs RJ45 cable (which is crossed over). I think it uses the TCP/IP standard.

Usually when I transfer small/medium sized files across the LAN, the file is copied without any problems.

However, larger files (100 Meg +) are not always transferred correctly, and they turn out to be corrupt when I try to use them. Copying them across again often solves the problem, but it is very tedious checking every file that I transfer.

How is this happening, and is there anyway I can get 100% perfect file transfers across my LAN?

 

[snootalope]

Do you have a cheap hub?? A pretty new Cisco switch might be the awnser.. Or it could even be trashy old nic cards! I should of been a doctor..

 

[Enkrypted]

I agree with snoop...I would setup your network to run with central hub. Sometimes running peer to peer may cause corrupted files.

Cordi

 

[Guest_imported]

There's no hub involved - I suppose its not really worthy of the title 'LAN', its just a home setup between two computers for backup/gaming purposes.

Expensive equipment would be overkill for this system, I just want to transfer files reliably between two PC's.

Maybe the NIC's are to blame, they were certainly cheap.

Data parity - if I copy a file on my hard drive and paste to another directory, the data ALWAYS remains the same, presumably because there is some sort of verification that the data is copied properly. Isn't there a similar verification system in place with TCP/IP? Maybe I should switch to NETbueieie or IPX for a more reliable connection?

Heck, I don't really know what I'm talking about, but there should be a way to reliably copy data down an Ethernet cable no matter how cheap the NIC's?

 

[ceh4702]

Crossover cables cant be trusted. If you do not like my post feel free to point out your opinion or my errors.

 

[Guest_imported]

So everybody is saying - spend more money, then your equipment will work ...

Surely 2 PC's running Windows XP should be trusted to send information to each other without messing up?
Either it should work 100% or not at all if the problem was duff hardware.
I run huge files across my LAN (10 Gig +), and it usually runs fine - but sometimes it messes up WITHOUT telling me, and my data is bad.

So I have to check my files every time I transfer them down the LAN, which is very slow and very boring.

Maybe somebody could recommend some software that can compare 2 sets of files, and inform me of any differences between the two?

Thanks for the help so far, unfortunately spending money on equipment isn't really practical in this case.

 

[ANFPS26]

Is your crossover cable shielded? Make sure it is not lying on the floor with the AC power cords it could be picking up some noise. "A little knowledge is a dangerous thing....."

 

[Guest_imported]

Look friend I think the problem is more simple that buying a new hardware or changing the one you have. I read in your post that you stablish the connection between your two PCs using a crossed over cable and using TCP/IP protocol, but when you connect two Windows PCs with a crossed over cable you most use NETBEUI protocol and maybe here is the cause of your poblem. For one or two year I had used in this way, connecting two Windows PC and never have any problem about corrupted file transfered from one PC to another. Try this and check what happen.

 

[tommarsh]

i transfer gigs at a time-p2p-just like you without any problems. I'm also using w2k though-but no matter.
tcp/ip will work fine-but NetBEUI is faster.
i don't beleive tcp/ip has any error correction.
check your cable-where did you get the cross over¿
i used to make my own but now you can guy them so cheap.
i hate to say "spend money" - but you may want to get two of the 'SAME' nic cards and a new $7 dollar cable.
what os are you using ¿
hope this helped, Tom
p.s. turn off your energy saving settings-i run everything on "NEVER" and just turn off the monitor when i walk away.

 

[BradSQLGuy]

The protocols are fine its your network cable. If you are connecting PC to PC you MUST use a straight through cable for consistency. I'm suprised a cross-over even works but I've never tried using a cross-over in that situation. Just a rule of thumb use a straight through if you are going from NIC to NIC. All other cases will be a cross-over. -Brad
A+, MCSE NT4, MCDBA SQL7

-Best cartoon of all time :-D 'Spongebob Squarepants'

 

[Guest_imported]

Thanks for the advice, everybody.

I installed NETBEUI on both the Win XP machines (despite Microsoft's best attempts to stop me), and initial impressions have been good - I've transferred several Gigs of information across without any difficulties so far.

I was under the impression that you HAD to use a cross-over cable in order to connect PC's directly to each other without using a hub - I'm happy to be proved wrong - but what would be the point of selling cross-over cables at all if normal RJ45 connected two PC's together without a hub? I'd be happy to buy an ordinary RJ45 if it did the job I need it to do .....

One problem I have with NETBEUI is that NETBEUI on its own won't let me access my internet connection over the LAN. Switching TCP/IP on solves this problem, but wouldn't my data transfers default to TCP/IP if Win XP is allowed to use both?
Switching TCP/IP off when I need to use NETBEUI is the workaround I am currently using.

If there is a way of configuring TCP/IP for Internet use and NETBEUI for normal data transfers it would be extremely useful!

PS I am using a 15m long cable, which may be contributing to a small amount of data 'dropping out' during the transfers?

 

[BradSQLGuy]

OMG I need more coffee. You are correct Thru you do need a crossover when going from NIC to NIC. About your NetBEUI question it depends on how you bind the protocols. If Netbeui is bound first then it will default file transfers there first and then TCP. You can just change the binding orders but it's possible this could slow your internet connectivity. -Brad
A+, MCSE NT4, MCDBA SQL7

-Best cartoon of all time :-D 'Spongebob Squarepants'

 

[tommarsh]

Sorry, but a crossover is required for a p2p (peer to peer)so the signal doesn't bounce back - by switching the 1st & 3rd wire and the 2nd & 6th (counting from the left of course)
Same thing with h2h (hub 2 hub)When using a hub-the crossover is done for you.
your system will be faster with just p2p-no hub needed.

A+,MCP+I,MCSE NT4

 

[tommarsh]

no problem with internet.
setup one machine (your best) for internet.
setup the other as a stand alone then setup your NetBEUI network from your stand alone to your best.
weather you want to enable sharing internet connection is up to you. this way you can leave your sensative data over the netbeui side.
best of luck, Tom

 

[Snickle]

I use a 10/100 peer-to-peer with a 5-port LinkSys hub, CAT5 cables, and get 100Mbps. Have found that cables too near/touching sub-woofer speakers, surge protectors, UPS's, lighting fixtures, electrical devices, can cause problems. Also, if the RJ45 connectors are not firmly crimped onto the cable, they can work loose due to temperature changes working the wires loose. Too much cable hanging down from the card/s can loosen the fit in the socket. The longer the transfer the warmer the wires can get which can lessen the speed, an electrical engineer can explain that the best.

 

[JimInKS]

Your initial post is correct that TCP/IP does do error checking and "theoretically" your setup should work.

I would guess it might be a driver/NIC/cable problem. Maybe with large files a buffer is being overrun or you are getting so many errors it is not handled properly. Changing to a protocol like NETBEUI may help correct this.

You might try looking at your network statistics and see if there are a lot of errors logged. If you see a lot of errors try a different cable or make sure the existing cable is not routed close to other electrical devices.

 

[Guest_imported]

Thanks again for all your help - I think I'm getting close to solving this problem.

I suspect that the cable is to blame for the data transfer problems. I never noticed any corrupted data over my old 10mRJ45 cross-over cable (although i rarely transmitted large files across that cable).
I like the idea of checking my network statistics using both cables, but how do I access these statistics (I am using XP Home edition)?

Switching to NETBEUI certainly seems to have improved things, but I am a novice where networks are concerned.

I can force my Network to use NETBIOS by going into Network Connections > Network Bridge > Properties and unchecking TCP/IP, IPX and NETBIOS. However, when I want to use the Internet using ICS, I have to switch all these back on again - not a very elegant solution.

Is it correct that I can set up File Sharing on NetBIOS and ICS on TCP/IP using the Network Connections > Advanced > Advanced settings menu? (I am using Win XP Home)

I have tried altering the bindings on this screen, but I can't seem to get the setup that I want.

Does anybody know the settings I should be using?

 

[Guest_imported]

Sorry, the last part should have read 'File sharing on NETBEUI' *doh*!