{ "metadata": { "name": "", "signature": "sha256:3bb6fed41815ab02f5db449f0fb6dc3bca89d7411c6822dfe382fccc1777b7c3" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 14: Mobile Network and Transport Layer" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 14.1, Page 452" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Variable declaration\n", "O=800*1000; #Object size(Bytes)\n", "S=536.*8; #max Segment Size(in bits)\n", "RTT=0.1; #Round trip-time in sec\n", "R=1.*10**6; #Transmission rate of the link from the server to the client in bps\n", "\n", "#Calculations\n", "Lmin=2*RTT+(O/R); #latency(msec)\n", "# For minimum latency (S/R) +RTT -(W*S/R) = 0;Therefore\n", "W=1+(RTT)/(S/R);\n", "\n", "#Results\n", "print 'The minimum possible latency is %d sec'%Lmin;\n", "print 'The minimum window size is %.1f segments'%W;" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The minimum possible latency is 1 sec\n", "The minimum window size is 24.3 segments\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 14.2, Page 452" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Variable declaration\n", "RTT=0.1; #Round trip-time in sec\n", "MSS=536.*8; #Maximum segment size in bits\n", "p=0.01;# packet loss probability for the path\n", "RTO=5*RTT; #Retransmission time out(from eqn 14.2 on page 450)\n", "\n", "#Calculations\n", "R=0.93*MSS/(RTT*math.sqrt(p));\n", "RR=MSS/(RTT*math.sqrt(1.33*p)+RTO*p*(1+32*p**2)*min(1,3*math.sqrt(0.75*p)));\n", "\n", "#Results\n", "print 'The upper bound of the throughput is %.4f Mbps'%(R*10**-6);\n", "print 'The throughput with retransmission due to errors is %.4f Mbps'%(RR*10**-6);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The upper bound of the throughput is 0.3988 Mbps\n", "The throughput with retransmission due to errors is 0.3341 Mbps\n" ] } ], "prompt_number": 2 } ], "metadata": {} } ] }