Hi,
you can refer to below application note and its SW package:
http://www.nxp.com/files/32bit/doc/app_note/AN4577.pdf
http://www.nxp.com/files/32bit/doc/app_note/AN4577SW.zip
FNET ethernet stack is used. There are examples for UDP, TCP/IP, web server...
The application note is written for MPC5646C but the ethernet module is the same on MPC5675K.
BR, Petr