Linking Hubs/Switches

[Songbird]

I am trying to connect a 5th hub to 4 hubs/switches.

First is this possible or is there a rule that you can only link 4 hubs together?

Second, does including switches to the configuration help extend the possible number of hubs/switches linked together?

Third, if it is possible, do I need to do something extra to make it work? If it's not possible, what do I need to do to add the 5th hub?

Thanks in advance for any help you can offer.

 

[goluman]

By a rule of thumb you cannot cascade more than three layers of hubs.By cascading it is meant that from one hub you connected another,from there you connect the next one and so on.This degrades n/w performance beyond aceptable limits as the hubs bring all nodes on the same collission domain.
You may attach the required hub on the main back bone though,but there are a lot of factors required to be taken into consideration the least of which are nuber of ports on your hubs/Switches,if they are 10or 100 Mbps.No of nodes conected to them,What kind of backbone,the kind of network Load etc etc.
YOu MAY attach another hub/switch on the main backbone but after 4 hubs/switches dont cascade the 5th

 

[ChrisAC]

Instead of cascading them hub to hub, why don't you just link each hub into a switch port.

For example, lets say that you have a 12 port switch, you could link port 1 of hub 1 to port 1 of the switch. You could then link port 1 of hub 2 to port 2 of the switch .. and so on!! That way you only ever cascade 2 devices!!

This is basically what you would do on a large network using access and distribution switches, but you would normally link them via fiber! You might have an access switch on each floor, linking back to a distribution switch in the main comms room. On your distribution switch you would have one or more fiber cards/blades to connect to the access switches.

With you hubs you can set up a similar situation, just using copper instead and linking into regular 10/100 switch ports!

Chris.

 

[ag6969]

I like crisac's answer, using switches as the backbone. However, make sure you use a segmenting swith, and not a desktop switch. A desktop switch could result in very poor performance because they are only intended to handle one address per port. They will of course be much cheaper. Look into the number of addressess per port supported by the switch first before buying, or it could just make things worse.

 

[ChrisAC]

Exactly right ag6969!! Personally, I would go for a Cisco switch, something like a 2924XL. It can handle upto 1024 MAC addresses per port, not that you would need that many of course!!

Chris.

 

[ag6969]

That's a lot of addresses!

 

[Guest_imported]

Hubs and switches are two different animals. Hubs share a collision domain whereas switches have an isolated collision domain on each port. Use a switch as your backbone and you can cascade up to 4 hubs per port on the switch. Beware of a
products labeled a "10/100 hub/switch." This is usually a 100 hub bus and a 10 hub bus and the only switching accomplished is between the busses

Dennis.

 

[Songbird]

I just wanted to thank everyone for their suggestions and tips. I eventually found a malfunctioning switch. I decided to replace that switch and both hubs. The system seems to be stable now. Thanks again.