Utilizing site write thresholds in a dispersed storage network

Abstract

A method for execution by a dispersed storage and task (DST) processing unit that includes a processor includes receiving a data object for storage via a network. A plurality of encoded slices are generated by executing an encoding function on the data object based on an information dispersal algorithm (IDA) threshold value. Site dispersal data indicating a plurality of site slice sets is generated, where each site slice set includes a number of unique encoded slices of the plurality of encoded slices that is greater than or equal to a site write threshold value. The site dispersal data further indicates a designated one of a plurality storage sites for each of the plurality of site slice sets. Each of the plurality of site slice sets is transmitted to the corresponding designated one of the plurality of storage sites via the network.

What is claimed is: 
     
         1 . A method for execution by a dispersed storage and task (DST) processing unit that includes a processor, the method comprises:
 receiving a data object for storage via a network;   generating a plurality of encoded slices by executing an encoding function on the data object based on an information dispersal algorithm (IDA) threshold value;   generating site dispersal data indicating a plurality of site slice sets, wherein each site slice set includes a number of unique encoded slices of the plurality of encoded slices that is greater than or equal to a site write threshold value, and wherein the site dispersal data further indicates a designated one of a plurality of storage sites for each of the plurality of site slice sets; and   transmitting each of the plurality of site slice sets to the corresponding designated one of the plurality of storage sites via the network.   
     
     
         2 . The method of  claim 1 , further comprising generating dispersal parameter data indicating the site write threshold value based on the information dispersal algorithm (IDA) threshold value and a maximum number of sites value. 
     
     
         3 . The method of  claim 2 , wherein generating the dispersal parameter data includes dividing the IDA threshold value by the maximum number of sites value to determine the site write threshold value. 
     
     
         4 . The method of  claim 2 , further comprising calculating the maximum number of sites value based on at least one of: a site availability level or a site reliability level. 
     
     
         5 . The method of  claim 1 , wherein each of the plurality of storage sites includes a plurality of storage units, wherein the site dispersal data further indicates a designated storage unit for each encoded slice in each of the plurality of site slice sets that is located at the corresponding designated one of the plurality of storage sites, and wherein transmitting each of the plurality of site slice sets includes transmitting each encoded slice in each of the plurality of site slice sets to the corresponding designated storage unit indicated by the site dispersal data. 
     
     
         6 . The method of  claim 1 , wherein each of the plurality of site slice sets is a proper subset of the plurality of encoded slices, and wherein the number of unique encoded slices of each site slice set is equal to the site write threshold value. 
     
     
         7 . The method of  claim 1 , wherein each of the plurality of storage sites are located in different physical locations. 
     
     
         8 . A processing system of a dispersed storage and task (DST) processing unit comprises:
 at least one processor;   a memory that stores operational instructions, that when executed by the at least one processor cause the processing system to:
 receive a data object for storage via a network; 
 generate a plurality of encoded slices by executing an encoding function on the data object based on an information dispersal algorithm (IDA) threshold value; 
 generate site dispersal data indicating a plurality of site slice sets, wherein each site slice set includes a number of unique encoded slices of the plurality of encoded slices that is greater than or equal to a site write threshold value, and wherein the site dispersal data further indicates a designated one of a plurality of storage sites for each of the plurality of site slice sets; and 
 transmit each of the plurality of site slice sets to the corresponding designated one of the plurality of storage sites via the network. 
   
     
     
         9 . The processing system of  claim 8 , wherein the operational instructions, when executed by the at least one processor, further cause the processing unit to generate dispersal parameter data indicating the site write threshold value based on the information dispersal algorithm (IDA) threshold value and a maximum number of sites value. 
     
     
         10 . The processing system of  claim 9 , wherein generating the dispersal parameter data includes dividing the IDA threshold value by the maximum number of sites value to determine the site write threshold value. 
     
     
         11 . The processing system of  claim 9 , wherein the operational instructions, when executed by the at least one processor, further cause the processing unit to calculate the maximum number of sites value based on at least one of: a site availability level or a site reliability level. 
     
     
         12 . The processing system of  claim 8 , wherein each of the plurality of storage sites includes a plurality of storage units, wherein the site dispersal data further indicates a designated storage unit for each encoded slice in each of the plurality of site slice sets that is located at the corresponding designated one of the plurality of storage sites, and wherein transmitting each of the plurality of site slice sets includes transmitting each encoded slice in each of the plurality of site slice sets to the corresponding designated storage unit indicated by the site dispersal data. 
     
     
         13 . The processing system of  claim 8 , wherein each of the plurality of site slice sets is a proper subset of the plurality of encoded slices, and wherein the number of unique encoded slices of each site slice set is equal to the site write threshold value. 
     
     
         14 . The processing system of  claim 8 , wherein each of the plurality of storage sites are located in different physical locations. 
     
     
         15 . A non-transitory computer readable storage medium comprises:
 at least one memory section that stores operational instructions that, when executed by a processing system of a dispersed storage network (DSN) that includes a processor and a memory, causes the processing system to:
 receive a data object for storage via a network; 
 generate a plurality of encoded slices by executing an encoding function on the data object based on an information dispersal algorithm (IDA) threshold value; 
 generate site dispersal data indicating a plurality of site slice sets, wherein each site slice set includes a number of unique encoded slices of the plurality of encoded slices that is greater than or equal to a site write threshold value, and wherein the site dispersal data further indicates a designated one of a plurality of storage sites for each of the plurality of site slice sets; and 
 transmit each of the plurality of site slice sets to the corresponding designated one of the plurality of storage sites via the network. 
   
     
     
         16 . The non-transitory computer readable storage medium of  claim 15  wherein the operational instructions, when executed by the processing system, further cause the non-transitory computer readable storage medium to generate dispersal parameter data indicating the site write threshold value based on the information dispersal algorithm (IDA) threshold value and a maximum number of sites value. 
     
     
         17 . The non-transitory computer readable storage medium of  claim 16 , wherein generating the dispersal parameter data includes dividing the IDA threshold value by the maximum number of sites value to determine the site write threshold value. 
     
     
         18 . The non-transitory computer readable storage medium of  claim 16 , wherein the operational instructions, when executed by the processing system, further cause the non-transitory computer readable storage medium to calculate the maximum number of sites value based on at least one of: a site availability level or a site reliability level. 
     
     
         19 . The non-transitory computer readable storage medium of  claim 15 , wherein each of the plurality of storage sites includes a plurality of storage units, wherein the site dispersal data further indicates a designated storage unit for each encoded slice in each of the plurality of site slice sets that is located at the corresponding designated one of the plurality of storage sites, and wherein transmitting each of the plurality of site slice sets includes transmitting each encoded slice in each of the plurality of site slice sets to the corresponding designated storage unit indicated by the site dispersal data. 
     
     
         20 . The non-transitory computer readable storage medium of  claim 15 , wherein each of the plurality of site slice sets is a proper subset of the plurality of encoded slices, and wherein the number of unique encoded slices of each site slice set is equal to the site write threshold value.