hubs and switches - Tilted Forum Project Discussion Community

simonrex22 · 07-08-2003, 11:57 AM

What is the difference between a hub and a switch?

mpedrummer2 · 07-08-2003, 12:32 PM

Hubs are stupid. They rebroadcast incoming messages out through all ports.

A switch has a bit of a brain in it. It "knows" who is where, reads the header packets, and passes the incoming packets out on the correct port only. In larger networks, this is an immense bandwidth saver. It also nearly eliminates packet collisions, which will speed up transfers considerably from one machine to another.

MPEDrummer

Cocktopus · 07-08-2003, 01:30 PM

hubs are lower (hardware) level

hrdwareguy · 07-08-2003, 01:59 PM

When you first install a switch it will act like a hub until it learns where recipients are, gradually you will see an increase in performance.

The_Dude · 07-08-2003, 02:53 PM

so, what about a router? where does it fit in

heyal256 · 07-08-2003, 03:19 PM

My understanding has always been that hubs are on the bottom (only allow network traffic 1 way at a time[ex. 100 Mb/s in 1 direction]), then you have switches (allows network traffic to flow 2 ways [100Mb/s in both directions]), then comes a router (allows network traffic both ways and tries to find the shortest route between point a and b).

It works out to
a switch = a smart hub
a router = a smart switch

a better example of the difference between a router and a switch are those dsl/broadband routers, the router has that extra port for your cable/dsl line. A switch would see it as an extra port, a router would "know" to direct all internet traffic to that port, but not direct any internal network traffic.

yodapaul · 07-08-2003, 03:58 PM

OK folks, time to clear a few things up here.
Hubs -- These are basicaly a multi port repeater. Everything that comes in on one port goes out on all the ports.

Switch-- This will direct traffic to the correct port using the MAC address included in the packet header. The switch will build a table up over time, as it learns which address is at what port.

Router-- There are a few different classes of routers the most popular for home users is a "single protocal" router. It acts kind of like a switch, but instead of using MAC addresses, a router will use the TCP/IP address to route the packets. A router also will build a table of what address is on what port.
The other type of router is the "multi protocal router". This type will route based on the address in the packet using many different protocals, such as IPX, TCP/IP, APPLETALK. These are the kinda of routers found in large networks.

hope this helps

hrdwareguy · 07-09-2003, 06:02 AM

One addition to what yodapaul said, on a larger scale router are used to route traffic much like a switch. However a switch will route traffic to a single machine while routers can route traffic for multiple IP's to a specific port.

For example, with a router you could do something like all traffic to address range 68.15.0.0 - 68.15.255.255 go out port A, all traffic to address range 64.200.0.0 - 64.200.255.255 go out port B.

tinfoil · 07-09-2003, 08:31 AM

A hub works on layer 1, the physical layer. It's more or less a splitter, and also amplifies the signal allowing for extending the domain. All connections on a hub are on the same collision domain.

A switch is layer 2, Datalink/Ethernet layer. A switch will remember the MAC addy of each port and determine which IP belongs to which MAC and store that in a built in table. Each port is a seperate collision domain, allowing full duplex between the port and the device on the other end. There are a number of different types of switches, but that is beyond the scope of this.

A router is typically layer 3, but some can go all the way to layer 7. As yodapaul said.

Imma go back to being stupid again.

billcollins · 07-09-2003, 12:12 PM

yay! one more explination.... this time including a Bridge

http://www.practicallynetworked.com/...idge_types.htm

Pragma · 07-22-2003, 05:38 PM

Layer 1 (Physical): Hub and Repeater - These devices take in traffic from one port and broadcast out all others (a repeater is basically a specialized version of a hub, with just two ports).

Layer 2 (Data Link): Switch and Bridge - These devices look at the MAC address and build a table of which port on the device has which MAC address. If it recieves a packet addressed to a MAC addy it doesn't know, it sends this out all ports except the one it recieved it from. A bridge is a specialized switch, with just two ports. (Advanced knowledge: Switches seperate collision domains and are used in microsegmentation, but that's probably not what you're asking).

Layer 3 (Network) - Routers and multilayer switches - Routers are used to choose the "best path" for a packet to travel, based on the destination IP and static routes that may be configured within the router itself. Multilayer switches are somewhat dumbed down versions of routers that operate on a simpler scale. They look at the IP and send to the corresponding port, but are faster switching packets in small networks, as they do all of the necessary computation in hardware, rather than software.

Layers 4-7 - You can have routers that forward packets depending upon information the packet carries in layers 4 through 7. These are normally used in QoS (Quality of Service) applications to ensure that, for example, the video conference between the corporate headquarters and the district offices recieves highest priority and thus doesn't suffer from bandwidth issues, while restricting traffic destined for Kazaa to have little to no bandwidth.

07-08-2003, 11:57 AM	#1 (permalink)
simonrex22 Insane	hubs and switches What is the difference between a hub and a switch?

07-08-2003, 12:32 PM	#2 (permalink)
mpedrummer2 Insane	Hubs are stupid. They rebroadcast incoming messages out through all ports. A switch has a bit of a brain in it. It "knows" who is where, reads the header packets, and passes the incoming packets out on the correct port only. In larger networks, this is an immense bandwidth saver. It also nearly eliminates packet collisions, which will speed up transfers considerably from one machine to another. MPEDrummer __________________ My sig can beat up your honor student.

07-08-2003, 01:59 PM	#4 (permalink)
hrdwareguy "Officer, I was in fear for my life" Location: Oklahoma City	When you first install a switch it will act like a hub until it learns where recipients are, gradually you will see an increase in performance. __________________ Gun Control is hitting what you aim at Aim for the TFP, Donate Today

07-08-2003, 02:53 PM	#5 (permalink)
The_Dude The GrandDaddy of them all! Location: Austin, TX	so, what about a router? where does it fit in __________________ "Luck is what happens when preparation meets opportunity." - Darrel K Royal

07-08-2003, 03:58 PM	#7 (permalink)
yodapaul Insane Location: MN	OK folks, time to clear a few things up here. Hubs -- These are basicaly a multi port repeater. Everything that comes in on one port goes out on all the ports. Switch-- This will direct traffic to the correct port using the MAC address included in the packet header. The switch will build a table up over time, as it learns which address is at what port. Router-- There are a few different classes of routers the most popular for home users is a "single protocal" router. It acts kind of like a switch, but instead of using MAC addresses, a router will use the TCP/IP address to route the packets. A router also will build a table of what address is on what port. The other type of router is the "multi protocal router". This type will route based on the address in the packet using many different protocals, such as IPX, TCP/IP, APPLETALK. These are the kinda of routers found in large networks. hope this helps __________________ I'm Just here to help. Now, Where is your problem? Last edited by yodapaul; 07-08-2003 at 04:02 PM..

07-08-2003, 01:30 PM	#3 (permalink)
Cocktopus Insane	hubs are lower (hardware) level

07-08-2003, 03:19 PM	#6 (permalink)
heyal256 Not so great lurker Location: NY	My understanding has always been that hubs are on the bottom (only allow network traffic 1 way at a time[ex. 100 Mb/s in 1 direction]), then you have switches (allows network traffic to flow 2 ways [100Mb/s in both directions]), then comes a router (allows network traffic both ways and tries to find the shortest route between point a and b). It works out to a switch = a smart hub a router = a smart switch a better example of the difference between a router and a switch are those dsl/broadband routers, the router has that extra port for your cable/dsl line. A switch would see it as an extra port, a router would "know" to direct all internet traffic to that port, but not direct any internal network traffic.

07-09-2003, 06:02 AM	#8 (permalink)
hrdwareguy "Officer, I was in fear for my life" Location: Oklahoma City	One addition to what yodapaul said, on a larger scale router are used to route traffic much like a switch. However a switch will route traffic to a single machine while routers can route traffic for multiple IP's to a specific port. For example, with a router you could do something like all traffic to address range 68.15.0.0 - 68.15.255.255 go out port A, all traffic to address range 64.200.0.0 - 64.200.255.255 go out port B. __________________ Gun Control is hitting what you aim at Aim for the TFP, Donate Today

07-09-2003, 08:31 AM	#9 (permalink)
tinfoil Fucking Hostile Location: Springford, ON, Canada	A hub works on layer 1, the physical layer. It's more or less a splitter, and also amplifies the signal allowing for extending the domain. All connections on a hub are on the same collision domain. A switch is layer 2, Datalink/Ethernet layer. A switch will remember the MAC addy of each port and determine which IP belongs to which MAC and store that in a built in table. Each port is a seperate collision domain, allowing full duplex between the port and the device on the other end. There are a number of different types of switches, but that is beyond the scope of this. A router is typically layer 3, but some can go all the way to layer 7. As yodapaul said. Imma go back to being stupid again. __________________ Get off your fuckin cross. We need the fuckin space to nail the next fool martyr.

07-09-2003, 12:12 PM	#10 (permalink)
billcollins Tilted	yay! one more explination.... this time including a Bridge http://www.practicallynetworked.com/...idge_types.htm

07-22-2003, 05:38 PM	#11 (permalink)
Pragma I am Winter Born Location: Alexandria, VA	Layer 1 (Physical): Hub and Repeater - These devices take in traffic from one port and broadcast out all others (a repeater is basically a specialized version of a hub, with just two ports). Layer 2 (Data Link): Switch and Bridge - These devices look at the MAC address and build a table of which port on the device has which MAC address. If it recieves a packet addressed to a MAC addy it doesn't know, it sends this out all ports except the one it recieved it from. A bridge is a specialized switch, with just two ports. (Advanced knowledge: Switches seperate collision domains and are used in microsegmentation, but that's probably not what you're asking). Layer 3 (Network) - Routers and multilayer switches - Routers are used to choose the "best path" for a packet to travel, based on the destination IP and static routes that may be configured within the router itself. Multilayer switches are somewhat dumbed down versions of routers that operate on a simpler scale. They look at the IP and send to the corresponding port, but are faster switching packets in small networks, as they do all of the necessary computation in hardware, rather than software. Layers 4-7 - You can have routers that forward packets depending upon information the packet carries in layers 4 through 7. These are normally used in QoS (Quality of Service) applications to ensure that, for example, the video conference between the corporate headquarters and the district offices recieves highest priority and thus doesn't suffer from bandwidth issues, while restricting traffic destined for Kazaa to have little to no bandwidth. __________________ Eat antimatter, Posleen-boy!