Editorial

Welcome to the first issue of the fourth volume of isecure. based on the editorial board decision, this issue is evoted to the extended/revised versions of some of iscisc'11 selected papers, which passed an additional review process by our referees. iscisc is an international conference on security and cryptology, initiated and being organized annually by the iranian society of cryptography (isc). the eighth series of this conference (iscisc'11) was held at the ferdowsi university of mashhad in september 2011. in this issue, we publish seven papers of this category. the title of the papers are similar to or the same as the corresponding papers in the conference, but the content was extended, and revised based on the comments received in the second (and possibly third) round of the review. in some cases, where the conference paper had been written in persian, the article appearing here was rewritten in english