Vinod,
We do have drivers for the Yokogawa WT230. You can always search our Instrument Driver Network through our website for third party drivers at www.ni.com/idnet. Here is a link to those specific drivers.
http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=1805
I have also attached a document that addresses the differences between a standard category 5 ethernet cable and a crossover cable, which can be purchased from our website.
http://digital.ni.com/public.nsf/allkb/34C3163EFAC9F30E86256B8F0060AD0C?OpenDocument
Have a great day!
Jordan G
