Adds RTT CDF plot.

plot_transmission_timeline.py

     else:
         plt.show()
 
+    #goodput cdf
     plt.clf()
 
-    print("Calculate and polt CDF...")
+    print("Calculate and polt goodput CDF...")
     plot_cdf(transmission_df, "goodput")
     plt.xlabel("goodput [mbps]")
     plt.ylabel("CDF")
 
     if args.save:
         plt.savefig("{}{}_cdf_plot.pdf".format(args.save, "goodput"))
+    else:
+        plt.show()
+
+    # rtt cdf
+    plt.clf()
+
+    print("Calculate and polt rtt CDF...")
+    plot_cdf(transmission_df, "ack_rtt")
+    plt.xlabel("ACK RTT [s]")
+    plt.ylabel("CDF")
+    plt.legend(["BBR"])
+
+    if args.save:
+        plt.savefig("{}{}_cdf_plot.pdf".format(args.save, "ack_rtt"))
     else:
         plt.show()