Of cource, possible
Technically, DFL-160 - the same DFL-210/800/1600
For example, refer to FAQ about DFL-DIR IPsec - http://www.dlink.com/support/faq/default.aspx?question=DFL-800&page=2
I didn't found DFL-DI example on exglish, but look for screenshots from russian - http://dlink.ru/ru/faq/92/520.html