Dear Joel Jaeggli, Jim Sermersheim, Scott W Brim, Brian E Carpenter and Dave Crocker Thank you all for the suggestion. I come from poor country, China. and would like to know the way of other countries. I guess that it is the often case individual company or citizen has such insurance. Anyway, I will try to figure out those stuff. Thanks again. Best wishes to you Sincerely yours -Hui _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf