Adding model abstractions to help flesh-out the concepts.
diff --git a/net/api/src/main/java/org/onlab/onos/net/device/DeviceService.java b/net/api/src/main/java/org/onlab/onos/net/device/DeviceService.java
index ac2f4a4..42b9a31 100644
--- a/net/api/src/main/java/org/onlab/onos/net/device/DeviceService.java
+++ b/net/api/src/main/java/org/onlab/onos/net/device/DeviceService.java
@@ -22,7 +22,7 @@
     MastershipRole getRole(DeviceId deviceId);
 
     /**
-     * Returns an iterable collection of the currently known infrastructure
+     * Returns a collection of the currently known infrastructure
      * devices.
      *
      * @return collection of devices