diff --git a/util/tracing/visualization/fedsd.py b/util/tracing/visualization/fedsd.py
index 9d482ab82..8739e83a7 100644
--- a/util/tracing/visualization/fedsd.py
+++ b/util/tracing/visualization/fedsd.py
@@ -334,9 +334,12 @@ def load_and_process_csv_file(csv_file) :
     # which boils up to having 'RTI' in the 'event' column
     df = df[df['event'].str.contains('Sending|Receiving|Scheduler advancing time ends') == True]
 
-    # Fix the parameters of the event 'Scheduler advancing time ends'
-    # We rely on the fact that the first row of the csv file cannot be the end of advancing time
-    id = df.iloc[-1]['self_id']
+    # Determine the "self id" in the trace file based on the first 'Receiving' or 'Sending' message (or use -1, the id of the RTI, if there is none).
+    id = -1
+    for index, row in df.iterrows():
+        if ('Sending' in row['event'] or 'Receiving' in row['event']) :
+            id = row['self_id']
+            break
     df['self_id'] = id
     df = df.astype({'self_id': 'int', 'partner_id': 'int'})