WIZnet WIZ108SR RS422/485-to-Ethernet Module
Provides quick, easy-to-use interface w/ 10/100Mbps Ethernet & 230Kbps RS-422/485 interface.

WIZnet W5300 Hardwired Network Protocol Embedded Ethernet Controller
Single chip w/ CMOS tech integrates 10/100 Ethernet controller, MAC, & TCP/IP for high-speed data communication.

WIZnet iEthernet W5200 Fast SPI Ethernet Controller
Enables internet connectivity for high speed SPI on single chip w/ TCP/IP stack & 10/100 Ethernet MAC & PHY.

WIZnet W5100 Hardwired TCP/IP Embedded Ethernet Controller
Provides Internet connectivity w/o OS, & includes hardwired, TCP/IP stack & integrated Ethernet MAC & PHY.