Design/Frames.md

@@ -134,6 +134,11 @@ Data is synchronised and organised into discrete frames that are represented by
 * **5.4** The pool should be maintained at a minimal size.
 * **5.5** The pool may expand or contract as necessary but infrequently.
 
+### 6. Concurrency
+* **6.1** A `Frame` only supports currency during stream receiving of data, but exposes a mutex.
+* **6.2** During receive, new channels may be added and changed in a thread-safe manner.
+* **6.3** The `store` operation and modification of persistent data must be thread-safe during the public lifetime of the `Frame`.
+
 ## Design
 
 ### Channel Status