How to add second ethernet port?

[craigmayhew]

I would like to use the raspberry pi as a router and firewall. This is mainly due to the raspberrypi using a fraction of the power of most routers. The wan connection would be ethernet and the lan connection would also need to be ethernet. Can anyone suggest or recommend a good breakout board (or some other alternative) that would allow me to add a second ethernet port?

[DougieLawson]

You can use a ENC28J60 on the SPI interface, but it's probably easier and better and faster and more reliable to buy a USB gigabit ethernet adapter.

[mahjongg]

I like the Microchips SPI ethernet solution, its great for embedded microcontrollers, but perhaps less so for systems that can already handle USB2. The one advantage would be not to overuse the single USB2 connection over which all communication must flow. Microchip offers excellent support, including a complete ethernet stack in source code.

But why the gigabit adapter, any cheap USB 10/100 base-T ethernet adapter would handle it just as well, using 1000 base-T doesn't make much sense when connected through USB2, and the other ethernet port being 10/100 Base-T, as it would offer no speed advantage at all. Unless the gigabit adapter would do extensive cacheing, making up for the limited up USB2 pipe, is that why you recommend it? I think a 10/100 base-T adapter would do that much as well.

[DougieLawson]

I'd choose the USB ethernet on a 2B.

[mikronauts]

While testing the Raspberry Pi 2, I was able to get significantly higher iperf results using a Linksys USB3.0 Gigabit Ethernet adapter than the on-board 10/100 Ethernet

http://www.mikronauts.com/raspberry-pi/ ... -review/6/

The improvement using the Gig-E adapter was significant when I was benchmarking the RPi 2 for NAS uses

http://www.mikronauts.com/raspberry-pi/ ... t-howto/3/

I like the Microchips SPI ethernet solution, its great for embedded microcontrollers, but perhaps less so for systems that can already handle USB2. The one advantage would be not to overuse the single USB2 connection over which all communication must flow. Microchip offers excellent support, including a complete ethernet stack in source code.

But why the gigabit adapter, any cheap USB 10/100 base-T ethernet adapter would handle it just as well, using 1000 base-T doesn't make much sense when connected through USB2, and the other ethernet port being 10/100 Base-T, as it would offer no speed advantage at all. Unless the gigabit adapter would do extensive cacheing, making up for the limited up USB2 pipe, is that why you recommend it? I think a 10/100 base-T adapter would do that much as well.

[allfox]

You can use a ENC28J60 on the SPI interface, but it's probably easier and better and faster and more reliable to buy a USB gigabit ethernet adapter.

Wow, I didn't know SPI at all.

ENC28J60 is a 10M Ethernet chip, I see there is ENC624J600 which is 100M.

Great, found something interesting.