The user installable IEEE 802.3 Ethernet module installs on the back of the printer (in place of the cover plate) and supports 10Base-T and 100Base-TX LAN communications. RJ45 CAT 5 cables up to 100m in length are supported. (PC23 Ethernet module has light case and PC43 Ethernet module has dark case, RoHS). Network Protocols Supported: TCP/IP, FTP, SNMP, LPR, HTTP.