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diff --git a/test_spec/vswitchperf_ltd.md b/test_spec/vswitchperf_ltd.md
index abae12c1..05711b37 100644
--- a/test_spec/vswitchperf_ltd.md
+++ b/test_spec/vswitchperf_ltd.md
@@ -514,6 +514,47 @@ The following represents possible deployments which can help to determine the pe
    - The average latency of the traffic flow when passing through the DUT (if testing for latency, note that this average is different from the test specified in Section 26.3 of [RFC2544]).
 
 <br/>
+ - #####Test ID: LTD.Throughput.RFC2544.PacketLossRatioFrameModification
+  **Title**: RFC 2544 X% packet loss Throughput and Latency Test with packet modification
+
+  **Prerequisite Test**: N\A
+
+  **Priority**:
+
+  **Description**:
+
+  This test determines the DUT's maximum forwarding rate with X% traffic loss for a constant load (fixed length frames at a fixed interval time). The default loss percentages to be tested are:
+    - X = 0%
+    - X = 10^-7%
+  Note: Other values can be tested if required by the user.
+  The selected frame sizes are those previously defined under [Default Test Parameters](#DefaultParams). The test can also be used to determine the average latency of the traffic.
+
+  Under the [RFC2544] test methodology, the test duration will include a number of trials; each trial should run for a minimum period of 60 seconds. A binary search methodology must be applied for each trial to obtain the final result.
+
+  During this test, the DUT must perform the following operations on the traffic flow:
+
+   - Perform packet parsing on the DUT's ingress port.
+   - Perform any relevant address look-ups on the DUT's ingress ports.
+   - Modify the packet header before forwarding the packet to the DUT's egress port. Packet modifications include:
+     - Modifying the Ethernet source or destination MAC address.
+     - Modifying/adding a VLAN tag.
+     - Modifying/adding a MPLS tag.
+     - Modifying the source or destination ip address.
+     - Modifying the TOS/DSCP field.
+     - Modifying the source or destination ports for UDP/TCP/SCTP  (Recommended).
+     - Modifying the TTL.
+
+  **Expected Result**:
+  The Packet parsing/modifications require some additional degree of processing resource, therefore the [RFC2544] Throughput is expected to be somewhat lower than the Throughput level measured without additional steps. The reduction is expected to be greatest on tests with the smallest packet sizes (greatest header processing rates).
+
+  **Metrics Collected**:
+
+  The following are the metrics collected for this test:
+
+   - The maximum forwarding rate in Frames Per Second (FPS) and Mbps of the DUT for each frame size with X% packet loss and packet modification operations being performed by the DUT.
+   - The average latency of the traffic flow when passing through the DUT (if testing for latency, note that this average is different from the test specified in Section 26.3 of [RFC2544]).
+   - The [RFC5481] PDV form of delay variation on the traffic flow, using the 99th percentile.
+<br/>
 
 [RFC1242]:(http://www.ietf.org/rfc/rfc1242.txt)
 [RFC2544]:(http://www.ietf.org/rfc/rfc2544.txt)