What's the difference between a hub, a switch, and a router?

This is a great resource site, Leo.

We are moving from a 6-computer office all running through an 8-port router connected to a cable modem. Our new offices are already networked to a closet where all 24 network lines terminate. We are continuing the Cable modem connection to the Internet, but I am thinking we will need a switch in addition to our router to accomodate all these new computers.

Am I right, and would it be wired this way -- cable into the cable modem, modem into the router, router into the switch, switch distributing to the computers?

Thanks for all your very helpful advice.

I would like to know if a switch would improve are perfomance at work instead of the Hub we currently have. I work in a hospital in maintence and due to are location the systems office ran one internet connection to our office since all of the computers are assigned IP's by the hospitals network we use a HUb to share this one connections with 5 computers. Could we use a switch instead of a hub and get our IP's from the hospitals network or would they be assigned by the switch.

A switch *should* just optimize the traffic, and not hand out IP addresses. A router (with DHCP or NAT) would hand out IP addresses. I typically don't recommend that in a corporate environment, just because it can sometimes interfere with site-specific configurations & applications.

Leo

Laura: yep, that's the approach I'd take if I were doing what you describe.

Good luck!

Leo

Thanks Leo, It helps me a lot.

Hi Leo, AWESOME SITE!

OK, I am curious as to when it is necessary to have a Router AND a Switch at the same time. I am basically setting up an office that has 3 computers, a printer, and a wireless access point. Would the best route be to go:

DSL --> Wireless Connection Router--> Computers & Printer?

If I want a LAN and access to the internet, should I include a switch in between the router and the computers/printer?

Thanks.

Ed

Thanks Ed :-).

The scenario you outlined doesn't need an additional switch. A router with enough ports to connect everything should handle the job just fine. I might add a switch is a) I ran out of ports on the router AND b) there's a lot of traffic between your computers. When b) isn't true, a switch will still work, but a hub would be fine as well.

Leo

leo, thanks so much for spending the time in answering all these queries. It really proves that the internet is an awesome place with some amazing people.

i have a config issue concerning 20 Pcs, 2 Servers and a Router / Firewall (Smoothwall(linux))

I am upgrading the network to switches;

3 x 16 port switches.

To connect these three together should i look for ones that have gigabit uplink connections. I can see that a bottleneck would be using 1 x 100mb port to connect to the other two switches in a daisy chain. Cost is an issue.

Also, whats the easist method of setting up a DMZ against my ADSL line? This would be to host apps to the public domain but not let them access the rest of the network.

Thanks again.
Nick

Actually, unless you expect VERY heavy traffic between your machines, 100mb should be just fine. Remember your internet side is limited by your DSL speed anyway.

DMZ would depend on the router. Typically they have a setting that allows you to specify the IP address of one machine to act as DMZ.

Leo

I have an ADSL connection with a dynamic IP. I wanna share 2 computers which can have internet access even the other pc is not powered on. I already have the ADSL modem. So will a switch do the job ?