--- /dev/null
+To identify performance changes due to TRex code development between previous
+and current TRex version, both have been tested in CSIT environment of latest
+version and compared against each other. All substantial progressions and
+regressions have been marked up with RCA analysis. See :ref:`trex_known_issues`.
+
+Physical Testbeds
+-----------------
+
+FD.io CSIT performance tests are executed in physical testbeds hosted by
+:abbr:`LF (Linux Foundation)` for FD.io project. Physical testbed
+topology used:
+
+- **1-Node Topology**: Consisting of TG with 1 NIC with 2 ports connected
+ together - loopback connection.