Editing Write Anywhere File Layout (section)

===File and directory model===
An important feature of WAFL is its support for both a [[Unix]]-style file and directory model for [[Network File System (protocol)|NFS]] clients and a [[Microsoft Windows]]-style file and directory model for [[Server Message Block|SMB]] clients.  WAFL also supports both security models, including a mode where different files on the same volume can have different security attributes attached to them. Unix can use either<ref>{{cite web|title=POSIX Access Control Lists on Linux |url=http://www.suse.de/~agruen/acl/linux-acls/online/ |publisher=Suse.de |url-status=dead |archive-url=https://web.archive.org/web/20070124223420/http://www.suse.de:80/%7Eagruen/acl/linux-acls/online/ |archive-date=2007-01-24 }}</ref> [[access control list]]s (ACL) or a simple bitmask, whereas the more recent Windows model is based on access control lists.  These two features make it possible to write a file to an SMB type of networked filesystem and access it later via NFS from a Unix workstation. Alongside ordinary files, WAFL can contain file-containers called [[Logical Unit Number|LUNs]] with required special attributes like LUN serial number for block devices, which could be accessed using [[Storage area network|SAN]] protocols running on [[ONTAP]] OS software.