Wires/cables/hub problem.

[aNoob]

OK, firts of all I don't know how to name the thread , so if the mods decide to change the title then so be it.
Bear with me for 10 seconds to explain my problem. I have cable internet. So , from the coax cable goes into the modem , from the modem , a cable goes to the hub in the uplink slot , from there in the PC I'm posting right now. Now,here's my problem : if I eliminate the hub from the equation the whole thing does not work anymore. That is , no network connectin at all (is an XP machine) hence no internet. As soon as I put the hub back , between the modem and computer it works flawlesly. Oh, and one more thing , the ISP says I'm not allowed to have 2 computers online , but they do not oppose to the router idea (like they can check how many computers I pass through the router).
Anyhow,does anyone have an idea what the problem is?
TA

[JayMan8081]

When changing the cable from the modem to the hub between the hub and your PC are you cycling the power on your cable modem? Whenever you change devices connected to the modem you need to cycle the power to re-establish the connection with your ISP.

[bburton]

Try removing power from your modem for a few minutes after you remove the HUB. Most modems are programmed internally to accept only ONE connection (that is MAC address, I think) at a time. This is to prevent people from connecting, say 10 computers to a HUB then uplinking the HUB to the modem (and hence using 10 IP adresses, which is a no-no unless you are paying for it).

Short answer, use a router. You can configure a PC running Linux to route and masq pretty easily. Just put two NICs in your computer, and then use the HUB to distribute to different computers on the inside (private) network. Or you could just buy a simple Linksys (or some other brand) hardware router.

If you are intersted in using Linux as a firewall, I recommend paying a visit here (http://www.linuxguruz.com/iptables/).

Good luck.

[soulestream]

make sure none of those cables are crossover cables. the hub would switch that over, but your computer would not. you (in theory) should not have to reboot XP or any operating system if you are using a hub, cause the hub doesnt have any information in it. it just passes the information to all ports. the only reason you may have to reboot is windows doesnt re-establish your connection upon plugging it back in.

As far as a router. if you want to hook more than 1 pc to the modem, you have to have a router. plus it will help hide your pc from the rest of the world. I would inverst the 30-40 bucks in a router.



soule

[aNoob]

Thx for the replies guys.Now , I have a router , that's not the problem. What I really don't understand is why with the hub I have connection and eliminating that one cuts my connection.And I don't mean here about internet connection , I mean about physical connection.
Look at this :

[modem]--cable1--[hub]--cable2--[computer]

The one above works flawlessly . Check what I did:

[modem]--cable1--[computer]

Now, this one does not work and I really don't understand why! It should work very good since is the same cable. I have tried my laptop where I have slack installed,same doodoo,media disconnected says. If this will work , then I will put a router instead the hub , but it doesn't. Could be cable1 the problem here? And if it is , why?
TA

Oh, sorry , the cables are not crossover , they are just normal cables,I have tried with several. I even made one and checked it/them.

[terets]

Problem is that the cable modem port is a 10 mb port. The hub is more than likely an auto sensing 10/100 hub. ( I'd scrap the hub man, unless you're doing packet analysis.)

Your card in your pc is probably a 10/100 card. However, auto sensing doesn't work all that well sometimes so I suspect your computer is trying to speak at 100mb and the modem at 10mb. That's a no-go for workie.

I'm assuming this is a true HUB and not a SWITCH or ROUTER of course.

Hope that helped.

[soulestream]

is the cable a crossover cable or a straightthrough cable


soule

[thaddaeus]

Also about the comment you made about the like they can check how many computers I pass through the router
It is possible if NAT is not enabled on the router. They will be able to see the diffrent devices connected to that cable modem if NAT isn't getting in the middle of things and they may block you or any machine above 2 from using the internet. With NAT enabled they only see the modem and the router.

[aNoob]

Originally posted by soulestream
is the cable a crossover cable or a straightthrough cable


soule

Is a straighttrough one.

[aNoob]

Originally posted by terets
Problem is that the cable modem port is a 10 mb port. The hub is more than likely an auto sensing 10/100 hub. ( I'd scrap the hub man, unless you're doing packet analysis.)

Your card in your pc is probably a 10/100 card. However, auto sensing doesn't work all that well sometimes so I suspect your computer is trying to speak at 100mb and the modem at 10mb. That's a no-go for workie.

I'm assuming this is a true HUB and not a SWITCH or ROUTER of course.

Hope that helped.

Is indeed what is called a switch I believe although on the box it says mini -hub. Problem is that if I get rid of the hub , I have no connection at all. In linux there's only the loopback and eth0 is not connected, in XP I have same message : media disconnected.Let alone internet...

[terets]

As i said, you need to change your speed and duplex settings on your eth0 card. Change to 10 and half.

mii-tool or some other executable on your linux distro will set your card speed.

[Bizza]

Hi there,

Ok, something that strikes me as odd...

You say that you are going into the uplink socket on your switch normally. This is strange because an uplink socket on a switch (or router) is usually a crossed port, so that you don't have to use a cross-over cable to connect it to the other switches on your network.

I would suggest trying to use a cross-over cable from your modem to computer, but that's crazy because you'd never do that, even if it worked, it would definately not be the correct setup to have.

Is there any kind of switch or button next to the port on the cable modem that might suggest it changes it from cross to straight? If so, press it and then try a staright cable to the PC.

It's very strange that is says there is no connection. Are the lights on the back of the network card lit when it's plugged in?

Also as for the duplex and line speed settings, I would recommend leaving them on auto.

Regards,
Biz

[aNoob]

Guys ,thank you for the support,now is working. A friend of mine came with a neat tool to check network cables and realized that cable one had 2 wires overlaping or something like that, I think they were 4 and 6 I'm not quite sure and frankly now I'm so excited that the whole setup works. So, I have changed the cable with another one , plug the router and voila! Hooking up my 3 PC's went like a breeze.
However , I have learned a hard lesson, next time if I see the same thing happening I will go straight and buy a wireless router. It will save me a lot from running from the 2nd floor to the first where the modem is , just to tell the cable guy which led is lit.
However , Thank you for your support!