Stupid question....

[Donny John]

What's the difference between a 4-port ethernet router and a 4-port ethernet switch?

[Moby-Dick]

lots

[Moby-Dick]

ok ...full answer

A switch manages trafic for a single network - a router is ised to activly pass traffic from one network to another , depending on a set of rules.

a 4 port router is usually a router with a 4 port switch built in.

( this is a very laymans definition btw before I get flamed )

[Donny John]

So could I replace my 4-port router which is attached to the cable modem and has 4 rigs plugged in (to share 1Mb internet connection) with a netgear 4/5 port switch?

[Moby-Dick]

nope as your cable modem can't do any routing.

the router is doing the Network Address Translation to allow your LAN boxes to connect to the web.

[Donny John]

Okay, thx Moby U da Man

[RVF500]

Techy answer. Switches are layer 2 (of the OSI model) devices and separate collision domains. Basically they deal with hardware addresses so can only pass traffic to directly connected devices. They don't 'know' about anything beyond that. Ok, there are layer 3 switches but these are essentially switches with a router added to them.

A router by definition is a layer 3 device that separates broadcast domains. Layer 3 works with logical addressing and can determine routes across networks. An ethernet router is really a router that only has ethernet ports (which operate at layer 2). A router can have many different interfaces from Ethernet up to high capacity optical interfaces.

A switch will hold a table of directly connected destinations and when a packet arrives simply transmits that packet out of the specific port it has learned for the destination. If it doesn't know the destination it simply broadcasts the packet out of all it's ports. It does not know about different network protocols. A router holds in it's routing table the routes to other networks. If a packet arrives that it does not have a destination for, and does not have a default route configured, it will drop the packet. It is aware of different network protocols, for example PPPoA (point-to-point protocol over ATM) which is a common protocol used in ADSL broadband. Interfaces can be configured to work on specific protocols. Ethernet being one of them.

BTW. I don't think it's a stupid question mate. Perfectly reasonable request for information