Abstract: A method begins by a processing module receiving an encoded data slice for storage. The method continues with the processing module obtaining metadata associated with the encoded data slice and interpreting the metadata to determine whether the encoded data slice is to be stored in a first access speed memory or a second access speed memory, wherein the first access speed memory has a higher data access rate than the second access speed memory. The method continues with the processing module storing the encoded data slice in a memory device of the first access speed memory when the encoded data slice is to be stored in the first access speed memory and storing the encoded data slice in a memory device of the second access speed memory when the encoded data slice is to be stored in the second access speed memory.

Abstract: A method for updating software in storage units of a dispersed storage network includes determining a software updating sequence pattern, which insures that, for each set of encoded data slices, a decode threshold number of encoded data slices is accessible. The method includes taking a set of the storage units off-line for software updating in accordance with the software updating sequence pattern. The method includes, when the software has been successfully updated in the set of storage units, putting the set of storage units back on-line and taking another set of the storage units off-line in accordance with the software updating sequence pattern. The method includes, when the software has been successfully updated in the other set of storage units, putting the other set of storage units back on-line and taking yet another set of the storage units off-line for software updating in accordance with the software updating sequence pattern.

Abstract: A method begins by a dispersed storage (DS) processing module selecting a set of distributed storage and task (DST) execution units for executing a task and determining dispersed storage error coding parameters for data. The method continues with the DS processing module dispersed storage error encoding the data in accordance with the parameters to produce a plurality of encoded data blocks and grouping the plurality of encoded data blocks into a plurality of encoded data block groupings. The method continues with the DS processing module partitioning the task into a set of partial tasks, outputting at least some of the plurality of encoded data block groupings to the set of DST execution units, and outputting the set of partial tasks to the set of DST execution units for execution of the set of partial tasks on the at least some of plurality of encoded data block groupings.

Abstract: A maintenance free storage container includes a container housing, storage servers, and a container controller. The container controller includes a processing module that is operable to maintain virtual storage server to physical storage server mapping information and to maintain storage server failure information. The processing module is further operable to dispersed storage error encode the virtual storage server to physical storage server mapping information to produce encoded mapping slices. The processing module is further operable to send the encoded mapping slices for dispersed storage outside of the maintenance free storage container. The processing module is further operable to dispersed storage error encode the storage server failure information to produce encoded failure data slices. The processing module is further operable to send the encoded failure data slices for dispersed storage outside of the maintenance free storage container.

Abstract: A method begins by a dispersed storage (DS) processing module of a storage unit receiving, over time, access requests regarding reading or writing of various data blocks. The method continues with the DS processing module establishing an internal verification access rate for verifying data blocks stored in a memory device of the storage unit based on a rate of the access requests and a maximum access rate of the memory device. The method continues with the DS processing module generating internal verification requests in accordance with the internal verification access rate, coordinating the internal verification requests and the access requests for accessing the memory device, and accessing the memory device based on the internal verification requests to verify the data blocks.

Abstract: A method begins by a dispersed storage (DS) processing module generating a shared secret key from a public key of another entity and a private key using a first modulo prime polynomial function, wherein a public key is generated from the private key using a second modulo prime polynomial function and wherein the public key of the other entity is derived using the second modulo prime polynomial function on a private key of the other entity. The method continues with the DS module encrypting a message using the shared secret key to produce an encrypted message. The method continues with the DS module outputting the encrypted message to the other entity.

Abstract: A method begins by a dispersed storage (DS) processing module receiving a first coded matrix that includes a first plurality of pairs of coded values corresponding to first data segments of a first data stream and a second data stream. The method continues with the DS processing module receiving a second coded matrix that includes a second plurality of pairs of coded values corresponding to first data segments of a third data stream and a fourth data stream. The method continues with the DS processing module generating a new coded matrix to include a plurality of groups of selected coded values. The method continues with the DS processing module outputting the plurality of groups of selected coded values to a requesting entity in a manner to maintain time alignment of the first data segments of the first, second, third, and fourth data streams.

Abstract: A method begins by a dispersed storage (DS) processing module generating a data object identifier for data to be stored in a dispersed storage network (DSN) and partitioning the data into a plurality of data partitions based on a set of retrieval preferences and data boundary information. For a data partition, the method continues with the DS processing module dispersed storage error encoding the data partition to produce a plurality of sets of encoded data slices and generating a plurality of sets of DSN addresses for the plurality of sets of encoded data slices, wherein a DSN address of the plurality of sets of DSN addresses includes a representation of the data object identifier, a representation of one or more retrieval preferences of the set of retrieval preferences, a representation of a corresponding portion of the data boundary information, and dispersed storage addressing information.

Abstract: A method begins by a processing module detecting a new storage unit within a dispersed storage network DSN. The method continues with the processing module determining to affiliate the new storage unit with a virtual memory vault, where the virtual memory vault is mapped to a set of storage units of the DSN, where data objects are dispersed storage error encoded into pluralities of sets of encoded data slices that are stored in the set of storage units. The method continues with the processing module determining virtual DSN addresses of the virtual memory vault to allocate the new storage unit. The method continues with the processing module updating vault information regarding the virtual memory vault to include the allocation of the virtual DSN addresses to the new storage unit.

Abstract: A method begins with a processing module receiving a request to store a data object from a first requesting device. The method continues with the processing module determining that a substantially similar version of the data object is currently stored in a DSN. The method continues with the processing module determining that a number of unique combinations of retrieving the plurality of sets of encoded data slices has exceeded a threshold and, when so, encoding, with a same decode threshold number and an increased pillar width number, the data object to create and store a plurality of sub-set of redundancy encoded data slices. The method continues with the processing module creating a unique combination of retrieving the data object for the first requesting device based on the plurality of sets of encoded data slices and the plurality of sub-set of redundancy encoded data slices.

Abstract: An integrity record is appended to data slices prior to being sent to multiple slice storage units. Each of the data slices includes a different encoded version of the same data segment. An integrity indicator of each data slice is computed, and the integrity record is generated based on each of the individual integrity indicators, and may be, for example, list or a hash of the combined integrity indicators. When retrieving data slices from storage, the integrity record can be stripped off, a new integrity indicator of the data slice calculated, and a new integrity record created. The new integrity record can be compared to the original integrity record, and used to verify the integrity of the data slices.

Abstract: A method begins by a dispersed storage (DS) processing module determining data block storage redundancy among a set of distributed storage and task (DST) execution units. The method continues with the DS processing module dispersed storage error encoding a data segment of data to produce a set of encoded data slices, where a first encoded data slice of the set of encoded data slices includes at least one redundant encoded data block in common with a second encoded data slice of the set of encoded data slices. The method continues with the DS processing module assigning a first partial task and a first encoded block processing order to a first DST execution unit regarding processing the first encoded data slice and assigning a second partial task and a second encoded block processing order to a second DST execution unit regarding processing the second encoded data slice.

Abstract: A method begins by a processing module generating a transaction number and generating at least a threshold number of dispersed storage network (DSN) concurrency requests, wherein each of the at least the threshold number of DSN concurrency requests includes a header section and a payload section; each of the payload sections includes the transaction number, a last known slice revision number, and a slice name section, wherein a first slice name section of a first one of the payload sections includes one or more first slice names that includes a first slice name corresponding to a first encoded data slice of a set of encoded data slices; and a second slice name section of a second one of the payload sections includes one or more second slice names that includes a second slice name corresponding to a second encoded data slice of the set of encoded data slices.

Abstract: A method begins by a processing module receiving a large data file for storage in a dispersed storage network (DSN) and determining initial dispersed storage error encoding parameters. The method continues with the processing module encoding, during a first time interval of receiving the large data file, first data segments of the large data file using the initial dispersed storage error encoding parameters to produce a first plurality of sets of encoded data slices. The method continues with the processing module writing the first plurality of sets of encoded data slices to the DSN and monitoring processing of the writing to produce first write processing performance information. When the first write processing performance information compares unfavorably to a desired write performance range, the method continues with the processing module adjusting, for a second time interval, the initial dispersed storage error encoding parameters to produce adjusted dispersed storage error encoding parameters.

Abstract: A method begins by a dispersed storage (DS) processing module determining to merge two data object level index nodes and merging the two nodes into a temporarily merged data object level index node. The method continues with the DS processing module initiating updating of a hierarchical ordered index structure by identifying an address for storing the temporarily merged data object level index node, setting up deletion of the two data object level index nodes, setting up linking the temporarily merged data object level index node to a next level node of the hierarchical ordered index structure, and determining whether a change has occurred to at least one of one or more of the two data object level index nodes and the next level node. When the change has not occurred, the method continues with the DS processing module commencing the updating of the hierarchical ordered index structure.

Abstract: A method begins by a dispersed storage (DS) processing module selecting two or more correlated error messages of a plurality of error messages. The method continues with the DS processing module identifying two or more collection of records corresponding to the selected two or more correlated error messages such that a collection of records includes an event record including information regarding an event, a first record including information regarding a dispersed storage (DS) processing module processing an event request to produce a plurality of sub-event requests, and a plurality of records including information regarding a plurality of DS units processing the plurality of sub-event requests. The method continues with the DS processing module identifying a correlation cause of one or more errors corresponding to the two or more correlated error messages based on the two or more collections of records.

Abstract: A method begins by a processing module receiving a file retrieval request for a file, wherein the file includes one or more data regions, and wherein a data region of the one or more data regions is divided into a plurality of data segments and stored as a plurality of sets of encoded data slices in a dispersed storage network (DSN) memory. The method continues with the processing module retrieving a segment allocation table (SAT), wherein a SAT entry of a plurality of SAT entries includes information regarding storing the data region in the DSN memory and a segmentation scheme regarding the dividing of the data region into the plurality of data segments. The method continues with the processing module identifying the plurality of sets of encoded data slices and retrieving at least a sufficient number of the plurality of sets of encoded data slices to regenerate the data region.

Abstract: A method begins with a processing module of a dispersed storage network (DSN) executing a write operation to write a plurality of sets of encoded data slices to DSN memory, where the write operation includes temporarily storing encoded data slices in cache memory. The processing module receives a read request for a portion of the data object and determines whether a decode threshold number of encoded data slices of a set is stored in the cache memory. When less than the decode threshold number of encoded data slices is stored in the cache memory, the processing module retrieves encoded data slices from the DSN memory to obtain the decode threshold number of encoded data slices, decodes the decode threshold number of encoded data slices to recover a corresponding data segment, and outputs the recovered corresponding data segment.

Abstract: A method begins by a processing module receiving data for dispersed storage, wherein the data has an associated user identification (ID), and obtaining a codec flag based on the associated user ID. The codec flag may indicate one or more codec types and a codec execution order. The codec types may include two or more of: a null data manipulation, one or more versions of a data integrity function, one or more versions of a compression function, and/or one or more versions of an encryption function. The method continues with the processing module manipulating the data to produce manipulated data utilizing the one or more codec types in the codec execution order, encoding the manipulated data using an error coding dispersal storage function to produce a plurality of encoded data slices, and sending the slices and codec flag to a plurality of DS storage units for storage.

Abstract: A method begins by a dispersed storage (DS) processing module identifying an encoded data slice having an error, where a storage unit of a dispersed storage network (DSN) stores the encoded data slice. The method continues with the DS processing module sending a lock command to the storage unit. The method continues with the DS processing module determining resolution for the error of the encoded data slice, where the resolution includes one or more of: rebuilding the encoded data slice, issuing a set of delete requests to storage units of the DSN regarding a set of encoded data slices, issuing a set of undo write requests to the storage units of the DSN regarding the set of encoded data slices, and issuing a set of roll-back write requests to the storage units of the DSN regarding the set of encoded data slices.