Hub/switch whats the difference?

[Lizardkng]

Ive heard that a switch has a notable performance increase over a hub.

Whats the difference in a hub and a switch?

We currenly have a DSL line into a Dell PowerEdge 1650 server with 2 NICs, NIC #2 is connected to a 3Com 24 port hub.

Hearing that a switch has a performance boost over a hub, should I consider an upgrade?

What type of performance will increase, overall network speed, internet speed, file transfers?

Ive tried to look up on other sites, but I cant seem to find a definitive answer.

 

[Aslamvs]

HI,

I will suggest you to go for the switch there are lots of differance bet HUB nad SWITCH. when in case of speed SWITCH is better that HUB.

check there links for more info

http://www.duxcw.com/faq/network/hubsw.htm

http://compnetworking.about.com/library/tips/blfaq011.htm

HTH Aslam

 

[Lizardkng]

Sorry, but the 2nd link didnt work?

Thanks for the help...now I just gotta convice the boss...and start pricing

 

[dankelt]

A switch will not nessesarily be faster than a hub, it depends on you network. In most cases a switch will be faster. The only advantage a hub has over a switch is the fact that it doesn't even look at the packets going through, meaning almost no latency. A switch has to examine each packet, and deside wich port to send it out on. If you have a small network, i'd say less than 8 nodes, and only a single server, then I would go with a hub. Otherwise the switch would be the much better choice. Also, switch prices have come down quite a bit, they are not much more than a hub.

As far as Internet speed goes, you will most likely not notice any difference.

You may notice some increace in speed in file transfers if users on your network are transfering to and from more than a single server. If you do only have a single server that is doing all the work, you will just be bound by the speed of that single port on the switch. In that case, you could always go Gigabit to the server

Hope this helps out!
Dan

 

[Lizardkng]

Great...thanks!

We do have a small network, only 8 clients, and 1 server that handles everything.

Our server already has 2 GigaBit NICs on board, but the rest of the network isnt ready for it yet. (hub/clients)

I wonder what it would cost us to get GB NICs in all the clients and a GB ready hub?

Guess a switch wouldnt help me too much...too small...

Thanks again.

 

[gbiello]

Lizardkng,
NICs will default to an auto-detect setting for speed and duplex in the Network Control Panel. *Sometimes* you can get a speed improvement by changing this setting from auto-detect to what it actually is. For a hub, it would be half-duplex. I don't know what speed your hub is 10 or 100 (probably 10), but try and change the settings to see if it helps.

-gbiello

 

[polymath5]

No doubt about get a switch. If you don't want the cost of getting a managed switch you can get an unmanaged switch for not much more than a hub.

Hubs by definition set up collision domains. A switch avoids them by 'memorizing' where mac addresses are and routing trafic there.

I wouldn't worry too much about Gig on the clients, (really depends on the apps you are running), but a switch with a gig port for server traffic, going to fixed 100FD clients will do you well.

A LOT depends on the applications you are running, if they involve a lot of net traffic, SQl databases, AD, etc., then every little bit helps. But if you just run some Office apps then you might not notice much difference.

The only issue with a non managed switch is if you are going to do some network sniffing, but that might be a concern for you. Hubs are great for that, as are managed switches. Might not be an issue for you.

Good luck! =============
Mens et Manus
=============

 

[dankelt]

Yup I agree with polymath5, if you already have the gig on the server, and can afford the switch with a single gig port, go for it.

 

[Lizardkng]

So the only advantage in GB is the link from the hub/switch to the server? No advantage in GB NICs on the clients or client to hub?

Sorry for the silly question, but I dunno anything about GB networking..

Oh, and our hub is 10/100.

I THINK its:

http://www.3com.com/products/en_US/detail.jsp?tab=features&pathtype=purchase&sku=3C16411-US

This one...

 

[dankelt]

Well, every gigabit switch I've ever seen only have a single gig port, but I haven't looked at them for quite a while. Basicly if you had just a 100 mb switch, then all your users would have to share the 100 mb to the server, if you put the server on a gig port all your clients will share the 1 gb to the server, almost guaranteeing them all 100 mb of their total max bandwidth.
Think of it as water flowing in pipes to the server, if all the little pipes (the workstations) flow into another little pipe (the server) your going to have a slowdown at the server. However if all the little pipes flow into a big pipe, then all the little pipes can flow to their full capacity.

Hope this make some sense!
Dan

 

[polymath5]

Dan makes another good point. Don't forget a hub agregates all the ports, so currently if you have a hub with 8 10Mb ports, every connection you plug into it decrements total bandwith to that port. A switch gives full bandwith to each port. Additionaly, because a switch looks at the packets it routes it directly to the destination port. A hub bounces all traffic through every port. =============
Mens et Manus
=============

 

[Doug1936]

I see some interesting takes on the differences between hubs and switches.

To simplify it, I think one should consider that with a hub all packets are sent to all ports, leaving it up to the NIC to accept traffic addressed to it and reject traffic not addressed to it. This requires CPU power on every computer connected to the hub.

A switch, for instance sends the packets ONLY to the addressed NIC card. This reduces network traffic somewhat, and does not require CPU power on the computers that are not addressed.

On small networks, the differences may or may not be significant, but on larger networks, the efficiency is very obvious.

The lower priced switches do not have any firewall capability as do the cheapest hubs, and network configuration should take this in consideration. On the other hand the managed switches can be configured to allow/disallow just about anything you wish.

 

[polymath5]

Personally, I much prefer to have a separate hardware firewall and a seperate router. Sorry, I must have missed where it was mentioned that the hub/switch had to do firewalling.

I wouldn't consider any of these cheap hubs as firewalls. What cheap hubs do firewalling? I'm really curious. =============
Mens et Manus
=============

 

[Stevehewitt]

Switch it. Like has been said previously, theres a little in the price between a decent unmanaged switch and a standard hub. Even if you don't get a instant gain in performance tell your boss that once you get a few more comps on the network the infrastruce could handle it with a switch, a hub will struggle if theres a server attatched to it. Switch all the way!!! Steve Hewitt
Systems Manager

 

[Shad007]

An 8 port 100mbit hub will only ever have a 10 or 100mbit backbone for it's connected users ie if one particular user sends a 100megabyte file to another user connected to the same hub, then it will pretty much cause the hub to fall over for everyone else.

A switch on the other hand will allow each port to utilize the full 100mb bandwidth available on the backbone. The Gigabyte ports on certain switches are usually dedicated to servers as they will be able to take the load of the entire switch very quickly (ie 10 users each sending 100mbyte files...). The other added bonus of a switch is 'Intelligent Manageability'. This is where the switch is actually given an IP on the network (as opposed to a 'dumb hub'). This way you can connect to the switch (either Telnet or in some cases browse to it via IE). Once connected to your switch you can do funky things like set port speeds, duplexes and manage flow control (on some GB switches)..its also a good place to start looking for network diagnostic issues as well (ie dropped packets, failed connections etc). Hubs do not provide this option.