W5100 Ethernet Module
This W5100 module is completely compatibale with Arduino Ethernet Shield, it is very easy to use it.

Original : https://www.emartee.com/product/42080/W5100%20Ethernet%20Module
Author : stmsky
Published On : unknown
This W5100 Ethernet module is made by stmsky.com. Unfortunately, stmsky.com is not an available site, but it still sells for $13.98 at emartee.com.
This module has the name SW5100, and they have still provided a short guide document.