slwong3

I am not sure if you can understand or not.

Router is actually uses IP address to determine the most efficient path to transfer data to destination.  (mostly used in multi network situation)
For example, I live in Toronto, if I transfer data to a person in HK, my data will have to go through a  lot of routers over the world.  Router would choose the best path.  

Switches uses MAC address to make decision of choosing path to transfer data to destination.  (the computer itself still uses IP address)  Switches are mainly used in a large LAN environment.  Switches can allow about 20 -50 computers connected to it.  It actually transfer data faster in a LAN environment because once the data is sent to a switch, it will pass the data to the corrent port for that destination computer.

Some switches have firewall function too.

For home purposes, your small router is just providing the switching function that normal switches can do because you probably only have 1 single subnet (1 single LAN) at home.

However, in a business world or office use, if there are 30 or 40 computers, you can connect all of them to one switch.  If the company has more than 1 department and each department has 30 or 40 computers.  Then each department can have 1 switch and all the switches are then connected to the router.  In this case, router is used to seperate each department into one subnet(which is the main function of a router).

(Note that, router normall does not support as many ports as switches do.  In order words switches allow more computer to connect to it.)

If you didn't study computer before, you might not understand what it means by subnet or MAC address.

slwong3

***you can buy either of them

***both router and switch can act as "DHCP" server which will hand out IP address to your computers (which means they both can help you get on internet)

but router is easier to use and has more functions because you can access the router by just typing the private IP address of the router
a small router with 4 or 6 ports supported is good enough for you already


you can just simply plug the ethernet cables for each computer to each port.  The router should be plugged to your "Internet connection modem" which is supplied by your service provider.

for the setting of your network card of your 3 computers, you can just leave it as "obtain IP address automatically".

By default, the router's IP address is 192.168.1.1 or 192.168.2.1 (depends on the manufacturer of your router, you can find it in the manual when you buy the router)
After you plug in all the cables, use "Internet Explorer", type in the address "http://192.168.1.1" or .2.1 depends on the router.  Then the router should prompt you for the administrator password.
The default password of the router can be found on the manufacturer's website or in the manual.  
After typing the password, you can now access the router and set up different things.

***You should first change the router's password to a different one for security purpose.

Secondly, you should specify the connection that you use for the internet.
I'm not sure your internet connection that you use in HK.  Some service provider would require username/password for you to get on internet.  This might be one thing that you need to set up for your router.
Normally, you can just leave your router as "obtain IP address automatically" just like the network cards of your computers.
(Router should now have 2 IP addresses.  One is for your private LAN which starts with 192.168.1.1.  The second IP address(external IP address) it should have is given by your Internet connection company.   If you set it up correctly, you should be able to view it on the router.)

Then you can set up the firewall, filter-032less connection, or even blocking certain computer in your house to go on internet

I think most of the people use router at home.
As I mentioned before, switch is usually used in big company which has a lot of computers in an office.
However, switch is actually as powerful as router.  It's just that they are used for different purpose.

Hopefully, this can help you to set up your own network at home.

slwong3

one more thing,
some small switches just support 5-8 ports which is good for home use too

For the small routers and switches for home use, their price are close too.

slwong3

Originally posted by gaye at 2005-8-6 02:06 AM:
Router 可以係 OSI 7 層中既 Level 3 ...

yes you're right