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+Feature
+=======
+
+Dispersed volume translator
+
+Summary
+=======
+
+The disperse translator is a new type of volume for GlusterFS that can
+be used to offer a configurable level of fault tolerance while
+optimizing the disk space waste. It can be seen as a RAID5-like volume.
+
+Owners
+======
+
+Xavier Hernandez <xhernandez@datalab.es>
+
+Current status
+==============
+
+A working version is included in GlusterFS 3.6
+
+Detailed Description
+====================
+
+The disperse translator is based on erasure codes to allow the recovery
+of the data stored on one or more bricks in case of failure. The number
+of bricks that can fail without losing data is configurable.
+
+Each brick stores only a portion of each block of data. Some of these
+portions are called parity or redundancy blocks. They are computed using
+a mathematical transformation so that they can be used to recover the
+content of the portion stored on another brick.
+
+Each volume is composed of a set of N bricks (as many as you want), and
+R of them are used to store the redundancy information. On this
+configuration, if each brick has capacity C, the total space available
+on the volume will be (N - R) \* C.
+
+A versioning system is used to dectect inconsistencies and initiate a
+self-heal if appropiate.
+
+All these operations are made on the fly, transparently to the user.
+
+Benefit to GlusterFS
+====================
+
+It can be used to create volumes with a configurable level of redundancy
+(like replicate), but optimizing disk usage.
+
+Scope
+=====
+
+Nature of proposed change
+-------------------------
+
+The dispersed volume is implemented by a client-side translator that
+will be responsible of encoding/decoding the brick contents.
+
+Implications on manageability
+-----------------------------
+
+The new type of volume will be configured as any other one. However the
+healing operations are quite different and maybe will be necessary to
+handle them separately.
+
+Implications on presentation layer
+----------------------------------
+
+N/A
+
+Implications on persistence layer
+---------------------------------
+
+N/A
+
+Implications on 'GlusterFS' backend
+-----------------------------------
+
+N/A
+
+Modification to GlusterFS metadata
+----------------------------------
+
+Three new extended attributes are created to manage a dispersed file:
+
+-   trusted.ec.config: Contains information about the parameters used to
+    encode the file.
+-   trusted.ec.version: Tracks the number of changes made to the file.
+-   trusted.ec.size: Tracks the real size of the file.
+
+Implications on 'glusterd'
+--------------------------
+
+glusterd and cli have been modified to add the needed functionality to
+create and manage dispersed volumes.
+
+How To Test
+===========
+
+There is a new glusterd syntax to create dispersed volumes:
+
+		gluster volume create <volname> [disperse [count]] [redundancy <count>]] <bricks>
+
+Both 'disperse' and 'redundancy' are optional, but at least one of them
+must be present to create a dispersed volume. The <count> of 'disperse'
+is also optional: if not specified, the number of bricks specified in
+the command line is taken as the <count> value. To create a
+distributed-disperse volume, it's necessary to specify 'disperse' with a
+<count> value smaller than the total number of bricks.
+
+When 'redundancy' is not specified, it's default value is computed so
+that it generates an optimal configuration. A configuration is optimal
+if *number of bricks - redundancy* is a power of 2. If such a value
+exists and it's greater than one, a warning is shown to validate the
+number. If it doesn't exist, 1 is taken and another warning is shown.
+
+Once created, the disperse volume can be started, mounted and used as
+any other volume.
+
+User Experience
+===============
+
+Almost the same. Only a new volume type added.
+
+Dependencies
+============
+
+None
+
+Documentation
+=============
+
+Not available yet.
+
+Status
+======
+
+First implementation ready.
+
+Comments and Discussion
+=======================