diff --git a/doc/architecture.txt b/doc/architecture.txt
--- a/doc/architecture.txt
+++ b/doc/architecture.txt
@@ -36,7 +36,7 @@ Concepts:
       numeric value of a frame identification value must be unique to that job. There are no
       restrictions of ordering of frame numbers except that they are not to be negative. There
       need be no sequencing of frame numbers either. Thus, a frame identification URL would look
-      like distren://<servername>/<jobid>/<frameid>
+      like distren://<servername>/<jobid>/frame/<frameid>
   - size: A frame hopefully represents a smaller unit of work in terms of the rendering
       back-end's capabilities. For example, POV-Ray's CLI can initiate and carry out the rendering
       of an entire animation. But distren would hopefully be able to provide a clean method for
@@ -56,3 +56,9 @@ Concepts:
       jobs registered in a server.
   - servers: A server, though having many more functions, shall be able to also perform the list
       of actions a client may perform.
+
+- file: There are different uses of files above and distributed rendering requires file distribution.
+  - file identification: Every file mentioned above was at least in the context of a job. Thus,
+      file identification numbers shall be assigned in the context of a job identification number.
+      They shall, however, be numeric.
+      distren://<servername>/<jobid>/file/<fileid>