difference between: switch - router - hub - bridge 1

[KryptoS]

Hey there,

can someone tell me what the difference is between: switches, routers, hubs and bridges???

thank you The One And Only KryptoS

 

[TruthPts2Itself]

FYI:

http://www.practicallynetworked.com/networking/bridge_types.htm

 

[hexn]

In plain and simple english:

A hub is a totally dumb device. If it gets a data signal, it just forwards it to everybody and hopes someone will pick it up.

A switch is just barely smarter. If it gets a data packet, it will try and find the device it goes to, and then send it to that device only, but the device MUST reside on the same subnet. A switch wont send data packets to computers on different subnets

A router is just barely smarter than a switch. It only gets a data packet if the destination computer isnt on the same subnet or LAN. The router then figures out where in the world that computer is located and then sends it in the right direction.

Hope that made sense. ~~~~~~~~~~~~~~

tech@shnypr.com

http://shnypr.com/tech

~~~~~~~~~~~~~~

 

[Guest_imported]

HUB: plug some computers into this, and all traffic is shared. In
other words, if computer 1 talks to computer 3, computer 2 will also
hear what computer 1 said. Usually computer 2 just discards traffic
not meant for it, but it does tend to burden your network.

SWITCH: if computer 1 talks to computer 3, computer 2 hears nothing.
On high-traffic networks, this means downloads & uploads go a little
faster for everyone. On low-traffic networks (home networks) users
typically don't notice a difference.

ROUTER: plug some computers into this, and it'll use port forwarding,
IP masquerading, and NAT to allow your computers to share an IP address
and connect to the internet. Cheap routers use HUB technology, good
routers use SWITCH technology.

You want a router with a few ports/jacks on it. Be sure it says "NAT"
on the box. If it also says "firewall" on the box, lucky you.

Lates,

TOO COOL

 

[walle]

For completion:
A "bridge" is a box to regenerate signals on a coax in coax-networks. As a fact every 500 meters, a new bridge needed to be placed in order to maintain a good signal.

Modern networks use switches intern (LAN) and a router to communicate with the internet (WAN).

Voila, the whole story.

 

[Guest_imported]

If you would like the "official" or text book distinction between these devices it is the level or layer at which they operate within the OSI model that distinguishes one from the other. As mentioned in previous replies hubs are pretty dumb... they work at the physical (lowest) layer of OSI and just pass on everything they hear to everyone. They do NOT understand any kind of addressing or filtering. Switches and Bridges are pretty similar, both operate at the Data Link layer (just above Physical) and both can filter data so that only the appropriate segment or host receives a transmission. Both filter packets based on the physical address (AKA MAC - Media Access Control - address) of the sender/receiver although newer switches sometimes include the capabilities of a router and can forward data based on IP address (operating at the Network Layer) and are referred to as IP Switches. Often the desired results could be achieved using either a switch or a bridge but *in general* bridges are used to extend the distance capabilities of the network while minimizing overall traffic, and switches are used to primarily for their filtering capabilities to create multiple, smaller virtual LAN's out of one large LAN for easier management/administration (V-Lan's). Routers work at the Network layer of OSI (above Data Link) and operate on the IP Address. Like switches and bridges they filter by only forwarding packets destined for remote networks thus mimimizing traffic, but are significantly more complex than any other networking device thus they require much more maintenance and administration, AKA Gateways.

 

[Guest_imported]

So what is a switching-hub? Just a more sophisticated piece of hardware that combines the functionalities of a switch and a hub, or is it something more? I can't seem to find anything recent on the Internet about switching-hubs, so are they still a technology that is being implemented today or have they been surpassed by more sophisticated hardware or just not being implemented in new network applications because they don't fit into newer network topology as well as other hardware? If they are still a typical or probable solution for current networking configurations in what circumstances would they be employed?

Any info would be appreciated.

Woodcutter

 

[hexn]

A switching hub, that is a very interesting question. I know there is such a thing as a hub that has one uplink port that you plug into another hub. This uplink port acts as a switch and filters traffic based on mac address.

 

[Guest_imported]

Im pretty sure switching hubs are switchs with no backplane (packet buffer memory). This means you will get collisions on it like a regular hub. But it does have a mac address table and forwards traffic like a regular switch I believe. These switching hubs are much cheaper.

-Later

 

[C4J]

This seems to be a nice dicussion going .....
Her is my bit.
1)a hub was the 1st way that ethernet cabling was used to connect via UTP to a cetral point (distribution). Prior to this we used coax cable to connect from 1 pc to next etc etc. This was total chaos if 1 PC got disconnected or the cable broke.
2)Hubs were 1st 10 Megs then 100 megs then auto sense hubs select between 10/100 depending on the netcard in the PC.
3) Then came switches or switched hubs (confusing I say, then came auto sense switches etc etc.
4) Now we get Level 1,2,3 etc swithces. As somebody has already explained that the switch will connect directly from PC to PC at what ever level (these switches have a price tag) and give the connecting PC 10/100/1000 speed.
4) Levels are related to the OSI stack.
5) Bridges as my understanding goes is that it wold connect unlike topologies together. Well that is now possible in todays HUBS/SWITHES etc.

C4J

 

[Guest_imported]

very nice answers....

 

[benjaminJ]

Hi,

this thread is very interesting and relevant to me!!!

i'm trying to set up a 8 pc gigabit home network for lots of data transfer and access to 2mb cable internet, and i would like to know if a switch and give you access to the net? and which of the following setups you reccomend -

8 port router connected to 8 pc's

8 port switch connected to 8 pc's

2*4 port switch connected to router.

 

[BurlyBoy]

You can't connect a switch directly to the internet and have it properly manage the PC's - that's what the router is for.
You could connect 1 PC directly to the internet and then to a switch - all other PCs could then connect to the switch. Using the proper software, u could then share the internet through the 1 PC. Windows XP has it built in and there are other nice product around as well to do this. But a router is definitely the way to go.

I currently have 5 PC's at home connected to the internet using:

1. the cable modem is connected to the WAN port on my 4 port 10/100 router. The internet needs a 10 mb port and will not work on a 100 mb port. My router also has a built in hardware firewall which is bulletproof. That way, all PC's connected thru it are protected - you can turn off any software firewalls you have on the PC's.

2. I then have 3 PC's connected directly to the router.

3. I have another separate 100 mbit switch connected to the router.

4. two other PC's are connected to the switch.

The 8 port router is the simplest, especially if you are going wireless. My setup grew over time, that's why a switch was added (free for me). I'm also using cat5 cables, so it means less cables having to travel all the way back to the router.

I can game with all 5 PC's connected to the internet OR host local LAN games.

cheers