diff --git a/scripts/dtls.test b/scripts/dtls.test
index fc902a4b9..72c87ac6a 100755
--- a/scripts/dtls.test
+++ b/scripts/dtls.test
@@ -35,8 +35,12 @@ cleanup () {
 
 trap cleanup err exit
 
-PROXY_PORT=1234
-SERVER_PORT=4321
+RANDOM_PORT_OFFSET=$(($RANDOM % 5000))
+echo "RANDOM=$RANDOM_PORT_OFFSET"
+PROXY_PORT=$((1200+$RANDOM_PORT_OFFSET))
+SERVER_PORT=$((1201+$RANDOM_PORT_OFFSET))
+echo "PROXY_PORT=$PROXY_PORT"
+echo "SERVER_PORT=$SERVER_PORT"
 KEY_UPDATE_SIZE=35
 NUM_TESTS_FAILED=0
 NUM_TESTS_RUN=0