difference

[714xkickz]

whats the difference between a switch and a hub? my network was set up like 6 years ago so my hub is really outdated and people running off the connections from the hub are getting slow speeds. i'm gonna get a new one but i'm not sure if i should get a switch or a hub

 

[MercenaryForHire]

Switch.

Switch.

A hub is "shared bandwidth" - all the traffic is sent to all the ports. Horribly inefficient. Slow. Insecure by design.

A switch only sends traffic to the proper location. Much, much, MUCH better.

There is no reason EVER to buy a hub now.

Ever.

Buy a switch.

- M4H

PS - Buy a switch.

 

[n0cmonkey]

Originally posted by: MercenaryForHire
Insecure by design.

Dumb switches are not more secure than hubs.

There is no reason EVER to buy a hub now.

You're wrong.

PS - Buy a switch.

Agreed.

Where's my shipping quote?

 

[ToeJam13]

whats the difference between a switch and a hub?

[*]Short answer:

A hub is dumb, a switch is smart


[*]Long answer:

There are three major differences between a hub and a switch. Although they both pass packets, its how they pass packets that makes them different.


First:

A hub is synonymous with being a multi-port repeater. Any data it receives on one port is freely transmitted out all other ports.

A switch is a path oriented, learning distributer. As data is received on a port, a switch examines the source and destination hardware (MAC) address embedded within that data. If the source address is new, it records the address and source port number. If the destination address is known, it will then forward the data only to the port the switch knows its on.


Second:

A hub is what's known as a half-duplex device. Several devices share a common transmission and receiption line on a network. Its like two or more people using a single pen and a single piece of paper to write down notes to each other. Only one person can do it at a time. As such, when two devices try to communicate at the same time, you get what's called a collision. It's much like two people reaching for the same pen. Both devices stop, wait a little bit, and try again. Since this waiting is different between devices, a second collision is avoided. However, as you start adding a lot of chatty devices, collisions go up exponentially. {1}.

A switch is a full-duplex device. If another full-duplex capable network device connects to a port on a switch, it will transmit and receive data simultaneously between itself that device. This is because a switch understands that only one other device sits at the far side of its transmit line. Its like two people with their own pens and sheets of paper writing down notes while looking at the same time to see what the other guy wrote on their sheet.


Third:

Since each port is equipped with the logic to handle all of these seperate one-on-one conversations, a switch is also granted the ability to negotiate a different rate of transmission on a per port basis. It's like using one hand to write notes to one person who is a fast writer, and another hand to write notes to a slow writer. As such, switches can negotiate different speeds per port, as well as different duplexes. {2}


Exceptions:

There are a few devices which break these rules. They are typically done for cost reasons, as they are blends between hubs and switches.

One device is known as a multi-speed hub, which normally acts like any other hub. However, it can accept several speed devices, and uses a special bridge chip to route data between the "low speed" portion of the hub with the "high speed" portion.

Another device is known as a full-duplex hub. Typically used with fibre-optic Ethernet devices, a full-duplex hub is able to both send and receive simultaneously. Usually a FIFO {3} buffer is used to pool all of the incomming data before its serialized and relayed out all of the other ports.


Notes:
{1} A half-duplex Ethernet network will begin to fail at around 15% network utilization. So many collisions exist that traffic simply can not be passed. A full-duplex Ethernet network is usually fine until 95-98%.

{2} On mediums that support half or full duplex.

{3} First-In, First-Out. Opposite of FILO: First-In, Last-Out

 

[spidey07]

the year is 2004. I don't think a hub has been manufactured for quite sometime now.

 

[Goosemaster]

Toejam13's response isawesome, but think of it in this sense if you are having trouble understanding it.

you=data

A hub is like a singles bar. Wretched in its experience becuase you have to mingle with other "data" slowing down the hook-up process(you geting to 3rd base with a cute blond).

Sometimes you "collide" with other segments as you try to chase the same blond.

basically, with a hub, all data is going everywhere. This means that traffic is going where it doesn;t need to go which means wasted, or used up, bandwidth. With many many clients hooked up to a hub, there are a lot of collisions because segments are being transmitted everywhere.


Now think of a switch as an online dating service. You get sent where you need to go, The MAC address table on the switch takes MAC info from connected clients and makes a table of addresses. In my scenario, it would be the menu at the dating service: "where do you want to go?"

Using the MAC address table, the switch sends data exactly where it needs to go by creating a virtual connection. Think of it as those can/string phones we had as kids. Basically the cans would be handed to the two parties that wanted to talk to each other. These "virtual" connections are nice because bandwidth is conserved as it is only being sent to set destinations. This reduces collisions a lot. Sort of like in an online dating service, you don;t have to look at the fat chicks if you don;t want to.....

we know you'll sneak a peak, but we won't tell.....

I was bored of using the same ole speech(although toejam did a marvelous job) and wanted to spice stuff up.
Hopefullyl I didn;t confuse the living hell out of you.

 

[n0cmonkey]

Originally posted by: spidey07
the year is 2004. I don't think a hub has been manufactured for quite sometime now.

I still see plenty of them on the shelves. Guess I should stockpile now...

 

[Goosemaster]

Originally posted by: n0cmonkey

Originally posted by: spidey07
the year is 2004. I don't think a hub has been manufactured for quite sometime now.

I still see plenty of them on the shelves. Guess I should stockpile now...

They aren't bad as some guy posted a nice informative review on here about them ( i wonder who? ), but I remember someone at an old job telling me that FCC regulations made switch use mandatory at least for some part of corporate/enterprise networks for security purposes. 1 MAC/port on the access switch so they could track you. Obviously you can use many MAC's per port so I don;t know how that holds up.

 

[spidey07]

Originally posted by: n0cmonkey

Originally posted by: spidey07
the year is 2004. I don't think a hub has been manufactured for quite sometime now.

I still see plenty of them on the shelves. Guess I should stockpile now...

there are some fools who still buy them I guess.


especially network operations center monkeys.

 

[n0cmonkey]

Originally posted by: spidey07

Originally posted by: n0cmonkey

Originally posted by: spidey07
the year is 2004. I don't think a hub has been manufactured for quite sometime now.

I still see plenty of them on the shelves. Guess I should stockpile now...

there are some fools who still buy them I guess.


especially network operations center monkeys.

Poor man's tap.

EDIT: Oh, and atleast one of my _old_ sun systems doesn't like the cheap netgear switches I buy, but I would be willing to bet that is an autonegotiate issue.

 

[n0cmonkey]

Originally posted by: Goosemaster

Originally posted by: n0cmonkey

Originally posted by: spidey07
the year is 2004. I don't think a hub has been manufactured for quite sometime now.

I still see plenty of them on the shelves. Guess I should stockpile now...

They aren't bad as some guy posted a nice informative review on here about them ( i wonder who? ), but I remember someone at an old job telling me that FCC regulations made switch use mandatory at least for some part of corporate/enterprise networks for security purposes. 1 MAC/port on the access switch so they could track you. Obviously you can use many MAC's per port so I don;t know how that holds up.

On some managed switches you can limit each port to a MAC address. Not that it provides you with much security or anything...

 

[ToeJam13]

Oh, and atleast one of my _old_ sun systems doesn't like the cheap netgear switches I buy, but I would be willing to bet that is an autonegotiate issue.

Oh, its not just the Netgears that have autonegotiation problems with Sun workstations. Cisco Catalyst switches, especially the older 5000/5500 series, are really bad for autonegotiation.

That's why in production/critical environments, I hard set everything to 100Mbit full-duplex. Piece of mind.

 

[n0cmonkey]

Originally posted by: ToeJam13

Oh, and atleast one of my _old_ sun systems doesn't like the cheap netgear switches I buy, but I would be willing to bet that is an autonegotiate issue.

Oh, its not just the Netgears that have autonegotiation problems with Sun workstations. Cisco Catalyst switches, especially the older 5000/5500 series, are really bad for autonegotiation.

That's why in production/critical environments, I hard set everything to 100Mbit full-duplex. Piece of mind.

I figured it was just an autonegotiate thing in general. And your solution wouldn't work for these sun systems.

 

[BeanDip]

Cisco Catalyst switches, especially the older 5000/5500 series, are really bad for autonegotiation.

That's because of the Spanning-Tree process looking for bridging loops. Enable portfast on the ports that you have problems with workstation autonegotiation. The reason is because the workstation is initializing and trying to get network info before the 50 seconds of port initialization.

Hubs are ok for home networks and small bandwidth networks but for peace of mind I always go with a switch for dedicated bandwidth on each port and no collisions.

 

[spidey07]

yeah, I remember 5000/5500s being terrible at auto negotiation - especially n-way or 3com cards.

but nowadays I haven't seen any negotiation problems at all.