What is dual Ethernet - how does it wok - whats the purpose. Any links?

Dual ethernet is simply two ethernet cards

why? to connect to two networks, perhaps to share an internet connection as a router... I'd imagine you'll probably not find much use for them (sorry, couldn't resist)

You can even have two ethernet to double the bandwidth to your switch/router. I don't have the exact detail on how to do it, but it does exist.

I've heard of this too. The way we have it setup on the servers at my school is that we dedicate each port to a certain channel ie one is the upstream and the other is the downstream. As to how they set it up, I think it's called duplexing... don't take my word for it though...

Duplexing: able to run upstream and downstream in the same cable simultaneously so theoratically a 100Mb/s ethernet can put out 200Mb/s.

PM 'fishmahn' if you want to know the exact details on how to run two cables to one switch/router.

Oh ok... well I was close, not.

Using 2 or more nics (or dual ethernet) in one server is called teaming.

The reason for two ports is to shared your connection with another computer, let's say you don't have a router and you got a DSL/Cable modem you can plug in your patch cable in the designated lan port, and then plug in another cable for the other lan port which act as a hub. Therefore you can still connect two computers to the Internet without using a router.

The part about 200mb/s or dual connection for two ports, I have never tried that, maybe it works maybe not

Often wodered this topic. Seems like a waste though as most cable modems have a few ports to plug into. I noticed on my motherboard that has two nics is that one can go up to 1gps will the other can only go up to 100mps.

Frenchy

There are plenty out there that can do 1000mbps on both ports too

Apart from Teaming, I use both ports on my P5W DH, one connects to my internal home LAN, and the other links over the roof to my neighbours LAN, allowing the two LANs to be isolated, but allowing me access to both. Mine is addressed in the 10.0.0.x range, and his in the 192.168.1.x range.

There are many situations where more than 1 port is usefull.

Some dual ethernet can be jointed to duplex the data flow , others serve as backup of data flow to reduce latency specially in Lan gamming...

Often wodered this topic. Seems like a waste though as most cable modems have a few ports to plug into. I noticed on my motherboard that has two nics is that one can go up to 1gps will the other can only go up to 100mps.

Frenchy

1GP/s ethernet is stardard but the question is, can your ISP provide 1gp/s that's the question. Both of my ports are dual gig per second

Using 2 ports at the same time to double your bandwidth is called Etherchannel, at least in the cisco world that is what is is called. However I have only heard of this being down between 2 pieces of networking equipment not a computer. In fact it may not be possible between a switch and a computer.

Most common uses are for a LAN connection (disk or print server) and the other for WAN (wide area network) uplink to the Internet.

http://www.nvidia.com/content/nfor [...] odule.html
There's a link to a Nvidia dual net site (just click on DualNet and then those teaming things).