Networking Question

[Caust1c]

What is the difference between a switch and a router? =)

[CGR]

Easiest way to explain it is:

A switch forwards traffic between machines on a local network

A router forwards traffic between networks.

[curtis1552]

Routers are for Internet connectivity through DSL, broadband, etc. - they connect your computers to an ISP
A switch connects computers on a intra-net (a local network) usually contained within your home or office.
A router can also act as a switch. The router has more hardware/software/programming to analyze and sort incoming data and makes sure it is redirected to the correct destination.
A hub is a low-end switch, usually used in a residential network.

Wiki
Switch (http://en.wikipedia.org/wiki/Network_switch)
Router (http://en.wikipedia.org/wiki/Router)

[Madwand]

A typical consumer router has a switch built in. It's a real switch, and works pretty much just like an external switch, but is integrated with the router for convenience.

But what doesn't a simple switch do that you need a router for? A simple switch doesn't allow you to share a single Internet connection by itself. It doesn't allocate IPs to all the connecting devices (DHCP). It doesn't provide a firewall that blocks random incoming Internet traffic.

[TempliNocturnus]

Read up on the OSI model. A switch operates on layer 2 (data link) and a router operates on layer 3 (network). A router looks at IP addresses, and determines where that packet wants to go, and which route to send it on to get to its destination.

A switch determines where to forward packets, based off of MAC addresses (layer 2 addresses). It's simply a box that is a single broadcast domain for everything plugged into it. A switch will memorize MAC addresses of every device that sends packets into it. It will then build a table of all known MAC addresses, and their corresponding physical ports, so that it then just has to make a brief connection between two ports when ever data is sent.

As apposed to a hub where all the bandwidth is shared, each device on the switch is given the full 10/100/1000 Mbps that the interface is rated for. A hub is simply a data bus, in which all the interfaces tap into. Therefore it's both a broadcast domain and a collision domain.

[Caust1c]

Thanks for all the help everyone! I think I understand the difference now, but I was looking at This (http://www.newegg.com/Product/Product.aspx?Item=N82E16833122140) "switch" on the Manufacturer Product Page and it said that it would split the internet. I like it because I can take it to small LAN Parties too, and it doesnt cost too much. Any advice?

[bLack0ut]

I'm probably wrong, but I always thought you can just plug the modem(dsl or cable) straight into the switch, and internet should be shared, as long as you manually set dhcp.

[Caust1c]

I'm probably wrong, but I always thought you can just plug the modem(dsl or cable) straight into the switch, and internet should be shared, as long as you manually set dhcp.

I hope so, I definitely want a plug and play router/switch, one that will work with DSL. =)

[smokie mcpott]

i have one of those switches on my network, and it will not split the internet. you will need a router of some sort to do that for you. there has to be a device in order to route the traffic to the correct ports for you.

[Caust1c]

Whats the point in getting a router and a switch if most routers include a switch? seems kinda redundant to me... and why aren't switches outdated then?

[smokie mcpott]

a switch can be used to extend a network beyond what a router can do, without the extra cost of buying more routers
example:
internet
|
router
| | | |
pc1 pc2 pc3 switch(8 port)
|
pc4 pc5 pc6 pc7 pc8 pc9 pc10

do that on a standard 4 port router without using wireless and no other switches


then there are scenarios like my home network...i dont have a router, i have a bsd box that functions as my firewall/dhcp server, sending a signal to an 8 port gig switch and to extend the capabilities of that to other rooms in the house, i added a 5 port gig switch (the one linked) so that all i had to do was run 1 long cable instead of 4

i have a total of 10 systems online now in my house...plus 2 laptops running on wireless (AP also built in my PFSense/freeBSD firewall box)
i cant do that on a standard router

[schnikies79]

A switch is not outdated because not everyone needs a router. A company may have a PC that is the DHCP server and then have huge banks of switches that connect the computers togethor.

Also, a router (consumer) usually has 4 ports. If you need more than that, you need a switch.

[Caust1c]

Okay. Switches->LANs
Router->Internet
right?
Anyways, I think ill beg my sister for her wireless router with 4 extra ports for a home LAN. (turn the wifi off though... dont want to get into security trouble...) Thanks for the help guys. You really cleared things up for me! =D

[bLack0ut]

Ah woops, you're right. I was thinking local network only, but one cable from a router into a switch will give all the computers connected to the switch internet access.

Switches are also good because you can get them in gigabit varieties for very cheap, ~$10-20.

[TempliNocturnus]

Yes, switches are very good to have for LAN parties, and no, a switch alone will not split the internet. If you really want to understand why, you really need to read up and understand the OSI model a bit (particularly the bottom three layers).

[curtis1552]

I've got my router plugged into a basic hub and it splits my internet between my XP computer and my Ubuntu computer.