-The second implementation is a single userspace program, named
-"switch", that integrates all three parts of an OpenFlow switch.
+The second implementation has the following components:
+
+ - udatapath, which implements the same functionality as the
+ Linux kernel module in userspace, at a cost in performance.
+
+ - secchan, a program that implements the secure channel
+ component of the reference switch (the same program used in
+ the kernel-based implementation).