instructions about directory structure / tools

README.md

@@ -1,6 +1,42 @@
 # COMUNDA
 
 This project contains labels for datasets released through
-<https://comunda.isi.edu>. Each leaf folder relates to a specific dataset
+<https://comunda.isi.edu>. 
+
+## Label directory structure
+
+All datasets are sub-grouped into letter directories based on the
+initial letter of the dataset name.  Within each letter directory is a
+directory for datasets that contain labels.  Within each dataset
+directory is a subdirectory from the creator of the labels, with
+"provider" being a reserved subdirectory name for labels that came
+from the dataset provider.
+
+As an example, labels created by the provider for the
+/B_Root_Anomaly-20190907/ dataset can be found in:
+
+    B/B_Root_Anomaly-20190907/provider
+
+In each subdirectory containing labels, please refer to the specific
+README file that describes the associated labels or tools to create
+the labels and how to use them.
+
+Each leaf folder relates to a specific dataset
 and contains labeling program if any, and information needed to
 run this program with the original dataset to obtain per-record labels.
+
+## Supporting tools
+
+In some cases, tools have created to "generate" labels using the
+dataset as an input.  These tools, and descriptions about how to
+compile and use them, will either be in the dataset subdirectory
+itself or may exist in the /tools/ subdirectory, under the label
+provider's owner name.  Generic tools like these will be referred to
+by specific label subdirectory README files when generic tools or
+scripts are to be used for label generation.
+
+As an example, the above /B_Root_Anomaly-20190907/ dataset requires
+tools from the "tools/usc-isi-antlab/ddos" directory and are
+referenced in the B/B_Root_Anomaly-20190907/provider/README.md file.
+These are generic tools that are used for many of the datasets
+prefixed with /B_Root_Anomaly-/.