CNT 4713

General

• Syllabus
  • Section 01
  • Section 02
• Exam Information will be posted here prior to exams.
  • Check the Canvas calendar for quiz dates.
  • Definition Quiz 1 - Wednesday, September 11. It covers definitions from the topics for Problem Set 1.
  • Problem Quiz 1 - Wednesday, September 18. It covers python and Problem Set 1.
    • Topics from Problem Set 1.
    • Python: expressions, lists, tuples, dictionaries, if statements, while loops, for loops, method declaration, import statements, comments.
  • Definition Quiz 2 will be on Wednesday, September 25. It will cover definitions from the topics for Problem Set 2.
  • Problem Quiz 2 will be on Wednesday, October 2. It will cover coding, problems and definitions from the topics for Problem Set 2.
    • Topics from Problem Set 2.
    • Python scripts from class and the problem set.
  • Defintion Quiz 3 will be on Wednesday, October 16. It will cover definitions from the topics for Problem Set 3.
  • Problem Quiz 3 will be on Wednesday, October 23. It will cover coding, problems and definitions from the topics for Problem Set 3.
  • Defintion Quiz 4 will be on Wednesday, October 30. It will cover definitions from the topics for Problem Set 4.
  • Problem Quiz 4 will be on Wednesday, November 6. It will cover coding, problems and definitions from the topics for Problem Set 4.
  • Defintion Quiz 5 will be on Monday, November 18. It will cover definitions from the topics for Problem Set 5.
  • Problem Quiz 5 will be on Monday, November 25. It will cover coding, problems and definitions from the topics for Problem Set 5.
  • Defintion Quiz 6 will be on Monday, December 2. It will cover definitions from the topics for Problem Set 6.
  • Problem Quiz 6 will be on the day of the final (TBA). It will cover coding, problems and definitions from the topics for Problem Set 6.
  • Defintion Quiz 7 will be on the day of the final, check the canvas calendar. It will cover definitions from the topics for Problem Sets 1-5.
  • Problem Quiz 7 will be on the day of the final, check the Canvas calendar. It will cover coding, problems and definitions from the topics for Problem Sets 1-5.
  • Exam 1 will be on Wednesday, September 28. It will cover chapters 1 and 2, along with CGI programming and web basics.
    • All topics and links on this page that look like this
    • All topics from Chapter 1 of the book
    • All topics from Chapter 2 of the book
    • All topics from the first 15 pages of the web basics reference
    • All topics from Homework 1
    • All topics from Quiz 1
    • Additional Chapter 2 Review Questions: R21 - R27, except R25.
    • Additional Chapter 2 Problems: P22 - P25, P27, P28, P31, P32, P35
    • Additional Python: UDP Client and Server, TCP Client and server. Applications that use TCP or UDP: Web server, UDP pinger, Web proxy, SMTP client.
  • Quiz 2 will be on Wednesday, 10/26. It will cover questions from the ends of chapters 3 and 9, which are listed in Homework 2.
    • Chapter 3 Review Questions: except R5 and R19.
    • Chapter 3 Problems: P1-P5, P8-P12, P14, P22-P27, P29, P31, P34-P37, P40, P43, P44, P46, P55
      • More information about cwnd.
      • Clarification about P43. P43 states that the Host A is capable of sending data into the TCP socket at a rate of S bps, where S = 10 * R. R is the transmission rate of the link. The book aslo mentions that Host A has a buffer. A better description is that Host A is capable of sending data into the buffer at a rate of S bps and the buffer can send data into the link at R bps.
  • Quiz 3 will be on Wednesday, September 27. It will cover questions from the ends of chapters 4, 5 and 8, which are listed in Homework 3.
    • Chapter 4 Review Questions: Several of the questions refer to virtual circuits; we did not cover them. You may omit the parts of any questions that refer to virtual circuits (VC). R1, R3, R8-R12, R15-R19, R21-23, R32, R33.
    • Chapter 4 Problems: P7, P9, P24-P28, P30-P32, P34, P42-P44, P46-P48
    • Chapter 5 Review Questions: R1-R3, R5-R12.
    • Chapter 5 Problems: P1-P6 P7, P11, P14-P17 -P19, P21, P22, P26, P31
    • Chapter 8: R1, R3, R5-R10, R13, R15, R16, R19, R20. Correction: R5 should read 8-bit block cipher.
    • Chapter 8 Problems: P1, P3, P5, P8, P12

    • Chapter 4 Sections

      • 4.1
        • 4.1.1
      • 4.3
        • 4.3.1
        • 4.3.2
        • 4.3.3
        • 4.3.4
      • 4.4
        • 4.4.1 - Skip fragmentaion
        • 4.4.2 - Only Network Address Translation (NAT)
        • 4.4.3
        • 4.4.4
      • 4.5
      • 4.6
        • 4.6.1
        • 4.6.2
        • 4.6.3 - Through BGP Basics
        • 4.6.4
      • 4.7
        • 4.7.1

      Chapter 5 Sections

      • 5.1
      • 5.3
      • 5.4
      • 5.7

  • Exam 3 will be during finals week. Check the Canvas calendar and your Panther Soft schedule for the time for your section. It will cover chapters 4, 5, 8, 6, and 7.
    • All topics from Quiz 3
    • Homework 3
    • Extra Credit 5
    • Additional Review Problems Since Quiz 3.
      1. Chapter 6: R3, R4, R6, R7, R11 (spoofed destination MAC address).
      2. Chapter 7: R1-R4, R6, R8, R9, R12-R14.
    • Additional Problems Since Quiz 3.
      1. Chapter 6: P1-P4.
    • List of notes from the in-class lectures:
      • Section 01: ch4_4-1_4-4_01, ch4_intro_01, ch4_4-5_01, ch4_4-7_01, ch5_5-1_01, ch5_intro_01, ch4_4-5_01_dup, ch5_5-2_01, ch4_4-6_01, ch5_5-3_01, ch5_5-4_01, ch8-01, ch8_intro_01, ch8_ssl_01, ch6_01, quiz3_review_01
      • Section 02: ch4_4-1_4-4_02, ch4_intro, ch4_4-5_02, ch4_4-7_02, ch5_5-1_02, ch5_intro_02, ch4_4-5_02_dup, ch5_5-2_02, ch5_5-3_02_real, ch4_4-6_02, ch5_5-4_02, ch5_5-4_02_redo, ch6_intro_02, ch8_intro_02, ch8_02, ch8_ssl_02, ch6_02, quiz3_review_02,
    • List of notes from the video lectures: ch7-7_1-7_3.
• GitHub Demo Videos.
  • UNIX Editors on ocelot.
  • Claiming your GitHub repository in my classroom and adding a file to it from the command line on ocelot.
  • Setting the username and email for git on ocelot. This will eliminate a common warning message on ocelot.
  • Creating a python script on ocelot.
  • Creating a web presence on ocelot.
  • Synching the web presence on ocelot to GitHub.

On-line resources

• GitHub Classroom

  You will use GitHub to demonstrate the work that you are doing for the class. You will use a repository that I manage from the GitHub Classroom site.

  • Section 01: Follow this link to claim your repo.
  • Section 02: Follow this link to claim your repo.
• Canvas
  • Canvas site, sections 01 and 02
• Zips of Class Notes
  • Section 01
  • Section 02
• Class Notes
  • Information
  • The password for the slides is netcentric.
  • List of lectures for section 01
  • List of lectures for section 02
  • List of video lecture notes for all sections.
  • List of video lecture notes for all sections, from previous semester.
• Textbook Site

  PowerPoint Slides

  The powerpoint slides are very good. You can read them faster than I can read them to you. I expect you to read the power point after you have read a chapter.

  Student Resources

  The student resources are excellent. They include applets, practice exercises, lab outlines. I expect you to take advantage of all of these resources.

  Access

  If you do not have an active code to access the site, you can purchase access on the site.

• Guide to Web Development with Java. Access the Look Inside feature from the Amazon page for this book. Read pages 1-18, which is all that is available in the Look Inside.
  • Video on HTML basics
  • Video on hypertext links and query string
• Python Resources
  • Python Tutorial at sthurlow.com
  • Python Docs
  • Python Tutorial at Brandeis (PPT Download)
• View some of the scripts from class.

Problem Sets

• Problem Set 1
  • Definitions
    • host, end system, communication links, packet switches, transmission rate, packet, router, link-layer switch, route, path, ISP, protocol, TCP, IP, internet standards, RFC, distributed applications, API, network protocols, network edge, clients, servers, access networks, DSL, cable internet access, HFC, FTTH, Ethernet, WiFi, physical medium, guided media, unguided media, UTP, coaxial cable, shared medium, fiber optics, terrestrial radio, satellite radio, geostationary satellite, LEO satellite, messages, store-and-forward, output buffer, output queue, queuing delays, packet loss, forwarding table, circuit switching, packet switching, circuit, end-to-end connection, FDM, TDM, bandwidth, silent periods, customer, provider, regional ISP, tier-1 ISP, PoP for ISP, multi-homed ISP, peer, IXP, content provider networks, nodal processing delay, queuing delay, transmission delay, propagation delay, total nodal delay, traffic intensity, packet drop, packet loss, traceroute, instantaneous throughput, average throughput, bottleneck link, layered architecture, service model, internet protocol stack, ISO OSI protocol stack, application-layer message, transport-layer segment, network-layer datagram, link-layer frame, payload field
  • Coding.
    • Claim a repo in the classroom for your section.
    • Post examples that you ran to help you learn Python. Here are some examples that you can try to implement: examples.
    • Create a web presence on ocelot.
  • GitHub Demo Videos.
    • UNIX Editors on ocelot.
    • Claiming your GitHub repository in my classroom and adding a file to it from the command line on ocelot.
    • Setting the username and email for git on ocelot. This will eliminate a common warning message on ocelot.
    • Creating a python script on ocelot.
    • Creating a web presence on ocelot.
    • Synching the web presence on ocelot to GitHub.
  • Problems
    • Chapter 1 Review Questions: R1, R4, R5, R11, R12, R13, R16, R18, R19, R23, R24, R25
    • Chapter 1 Problems: P3, P4, P8, P10, P13, P20, P24, P29a, P31.
• Problem Set 2
  • Definitions from 2.1, 2.2, 2.3, 2.7 (the FTP terms are only in the lecture notes)
    • application architecture, client-server, data center, P2P, self-scalability, ISP friendly, P2P security, P2P incentives, messages, API, IP address, port number, reliable data transfer, loss-tolerant applications, bandwidth-sensitive apps, elastic applications, TCP connection, UDP, application-layer protocol, HTTP, web page, HTML file, web browser, web server, stateless protocol, non-persistent connection, persistent connection, RTT, request message, request line, header lines, response message, status line, header line, entity body, cookies, set-cookie, web cache, proxy server, conditional GET, if-modified-since, control connection, data connection, out-of-band, in-band, state, USER, PASS, LIST, RETR, STOR, user agents, mail servers, SMTP, mailbox, message queue, SMTP handshake, HELO, MAIL FROM, RCPT TO, DATA, QUIT, mail message formats, From, To, Subject, POP3, user, pass, list, retr, dele, quit, IMAP, port number, socket, UDP, socket(), sendto(), recvfrom(), close(), bind(), TCP, connect(), send(), recv(), listen(), accept()
  • Coding.
    • Continue to post examples from class in GitHub.
    • Assignment 1 from Chapter 2.
      • Start with the TCP Server code from class. You may want to implement the TCP Client to test that the server works. Create a web server will process file requests.
      • To avoid conflict, request a port for your server from my port site: Request Port
      • After your server is running, add a link from your index page to a file that your server can handle. Replace your port number and filename in this link:
        <a href="http://ocelot.aul.fiu.edu:9999/filename.ext">Existent File</a>
      • Next, add a link from index page to a file that your server does not handle, to see your 404 error page. Replace your port number and non-existent filename in this link:
        <a href="http://ocelot.aul.fiu.edu:9999/nofilename.ext">Non-Existent File</a>
    • Assignment 2 from Chapter 2.
      • Start with the UDP Server and UDP Client code from class.
      • Configure the server so that it randomly drops packets.
      • Allow the client to give up if no response has been reveived within 1 second.
      • Include information about how long each response took. This will be the RTT.
  • Labs
    • Wireshark Lab: HTTP
  • Problems
    • Changes from the sixth edition (6e)
      • Section 2.3 (FTP) in 6e is removed from 7e.
      • Section 2.4 in 6e is Section 2.3 7e.
      • Section 2.5 in 6e is Section 2.4 7e.
      • Section 2.6 in 6e is Section 2.5 7e.
      • Section 2.6 in 7e is Sections 7.2.3, 7.2.4, 7.2.5 in 6e.
    • Chapter 2 Review Questions: R1 - R8, R10 - R14, R16, R26, R27
      Additional question:
      • Why is it said that FTP sends control signals "out-of-band"?
    • Chapter 2 Problems: P1, P2, P4, P5, P9, P10, P11, P14, P15, P17.
      Additional problem:
      • Read RFC 959 for FTP. List all of the client commands that are supported by the RFC
• Problem Set 3
  • Definitions from 2.4, 2.5, 3.1, 3.2, 3.3, 3.4
    • hostname, IP address, domain name system, DNS, host aliasing, canonical name, mail server aliasing, load distribution, single point of failure, traffic volume, distant centralized database, maintenence, distributed hierarchical database, root DNS server, TLD servers, authoritative servers, local DNS server, recursive queries, iterative queries, DNS caching, RR, name, value , type, TTL, type: [A, NS, CNAME, MX], DNS message format, header section, question section, answer section, authority section, additional section, nslookup program, registrar, scalability, minimum distribution time P2P, minimum distribution time client-server, BitTorrent, rarest first, unchoked, optimistically unchoked, segments, logical communication between processes, logical communication between hosts, UDP, TCP, best-effort-delivery service, unreliable service, reliable data transfer, congestion control, sockets, demultiplexing, multiplexing, source port, destination port, well-known port number, UDP, connectionless multiplexing, connectionless demultiplexing, assigned port, bind to a port, return address, TCP, connection-oriented multiplex, connection-oriented demultiplexing, welcome socket, port scanning, same port on different hosts, http well-known port is 80, UDP offers minimal transport service, multi/demultiplex, light error checking, connectionless, DNS over UDP, app controls data, no connection establishment, no connection state, small packet overhead, checksum, 1s complement sum, in-memory error detection, end-end principle, unidirectional data tranfer, perfectly reliable channel, FSM, rdt_send(), rdt_recv(), udt_send(), deliver_data(), make_pkt(), extract(), positive acknowledgement, negative acknowledgement, ARQ, error detection, error recovery, receiver feedback, retransmission, isNAK(), isACK(), corrupt(), stop-and-wait protocol, channel with bit errors, duplicate packets, sequence number, duplicate ACKs, lossy channel, bit errors, duplicate data packet, countdown timer, alternating-bit protocol, pipelining, Go-Back_n, window size, sliding-window protocol, cumulative acknowledgment, Selective Repeat
  • Coding.
    • Continue to post examples from class in GitHub.
    • Assignment 1 from Chapter 2.
      • Complete any missing features to the web server assignment from last week.
      • Implement the conditional GET. The server should be able to accept requests from existing HTTP clients, like Firefox and Chrome.
    • Assignment 3 from Chapter 2.
      • Start with the Mail Client script.
      • Modify the script so it can accept input from an HTTP browser. You may think of this script as a web server, whose purpose is to send email, instead of serving files.
      • On first call, the script should display a simple HTML page that contains a form.
        • The form should accept the From and To addresses, along with the Subject and Message.
        • When the button is clicked, the data should go to the port on ocelot that is associated with the mail script. Redisplay the HTML page with the form, with the user's data from the email filled in. Add a message that the mail was sent. Use mod_html.py to parse the query string.
        • You do not need error processing for this script. That feature will be added in the future.
  • Labs
    • Chapter 2 - Wireshark Lab: Exploring DNS
    • Chapter 3 - Wireshark Lab: Exploring TCP
    • Chapter 3 - Wireshark Lab: Exploring UDP
  • Problems
    • Chapter 2 Review Questions: R19 through R23 (6: 21-24)
    • Chapter 2 Problems: P19, P22, P25, P28, P29 (6: P19, P22, P25, P27, P28)
    • Chapter 3 Review Questions: R1, R3 through R13
    • Chapter 3 Problems: P1 through P5, P8, P11, P12, P22, P23, P24
• Problem Set 4
  • Definitions from 3.5, 3.6, 3.7 (E7: skip 3.7.2), 4.1, 4.2, 4.3
    (Edition 6: 3.5, 3.6, 3.7, 4.1, 4.2.2, 4.3, 4.4; E6 is missing 4.2.5 from E7)
    • connection-oriented, full-duplex, point-to-point, three-way handshake, send buffer, max segment size (MSS), max transmission unit (MTU), TCP segments, checksum, sequence number, acknowledgement number, receive window header field, header length field, options field; ACK, SYN, FIN flags; cumulative acknowledgement, piggybacked acknowledge, RTT, fast retransmit, selective acknowledgement, flow control, congestion control, receive window, SYNACK segment, end-end control, network-assisted control, choke packet, ATM ABR congestion control, resource-management cells, CI and NI bits, self-clocking, congestion window, lost segment, acknowledged segment, bandwidth probing, slow start, congestion avoidance, fast recovery, TCP Tahoe, TCP Reno, additive increase, multiplicative decrease, fairness, Routing, Forwarding, Forwarding table, network service model, guaranteed delivery, guaranteed delivery with bounded delay, in-order packet delivery, guaranteed minimal bandwidth, guaranteed maximum jitter, security services, best-effort service, longest prefix matching, Prefix match, Link interface, Input ports, Switching fabric, Output ports, routing processor, control plane, Switching via memory, Switching via bus, Switching via interconnection network, HOL, packet loss, IPv4 datagram format - all fields, dotted-decimal notation, CIDR, DHCP, Temporary IP address, Plug-and-play protocol, DHCP discover message, DHCP offer message, DHCP request message, DHCP ACK, NAT, NAT translation table, ICMP, IPv6 datagram format - all fields, Dual-stack, Tunneling
  • Coding.
    • Continue to post examples from class in GitHub.
    • Assignment 1 from Chapter 2.
      • Complete any missing features to the web server assignment from last week.
      • Implement the accept-language header.
        • The header will be in a format like en, es, de.
        • Create multiple versions of a file named hello.html, but with an additional extension of the language abbreviation, like hello.html.en, hello.html.es, hello.html.de. Each file will have 'hello' in it in the appropriate language.
        • If the user requests hello.html, look at the accept-language header and check if one of the languages has a file for it. Choose the first on in the list that is also a language that your site supports. Return the language file.
      • Demo HTTP Accept-Language
    • Implement an FTP client.
      • Use the FTP client from the lectures. Use your email for the anonymous log in.
      • Display a page that contains the listing of the root index of the server.
      • Have a text box for the user to enter the name of the file or directory from the current directory. Use POST to pass the data to the server.
      • If the name is for a file, then download it. If the name is for a directory, then redisplay the page with the new directory listing.
      • Demo FTP Client
  • Problems
    • Chapter 3 Review Questions: R14 through R18
    • Chapter 3 Problems: P25 through P29, P31, P34 through P37, P40, P44, P46
    • Chapter 4 Review Questions:
      6th Edition: R3, R8 through R12, R15, R17, R18
      7th Edition: R3, R10 through R13, R21, R24, R17, R26
    • Chapter 4 Problems:
      6th Edition: P7, P9, P10, P11, P12, P13, P20, P21
      7th Edition: P2, P4, P5, P6, P7, P8, P14, P15, P16
• Problem Set 5
  • Definitions from 5.1, 5.2, 5.3, 5.4, 5.6, 6.1, 6.2, 6.3, 6.4.1
    (Edition 6: 4.5, 4.6.2, 4.6.3, 4.4.3, 5.1, 5.2, 5.3, 5.4.1)
    • Graph,Nodes,Edges,Path,Least-cost path,Shortest path,Global/Centralized routing algorithm,Link-state algorithm,Decentralized routing algorithm,static routing algorithm, dynamic routing algorithm, load-sensitive algorithm, load-insensitive algorithm, Distance-vector algorithm,Bellman-Ford equation,Routing tables,Routing loop,Count-to-infinity,Poisoned reverse,Message complexity,Speed of convergence,Robustness, scale, administrative autonomy,AS,Intra-AS routing,gateway router,OSPF,OSPF security,Multiple same-cost paths,OSPF support for hierarchy,Area border routers,Backbone,Inter-AS routing,BGP,BGP peers,eBGP,iBGP,AS-PATH, NEXT-HOP, hot potato routing, Prefix reachability info from neighbors,Determining best route,gateway router,internal router,semi-permanent TCP connection,route-selection,local preference,routing policy,multi-homed access IP, ICMP,traceroute,echo reply,dest protocol unreachable,dest port unreachable,echo request,TTL expired, node,link,link-layer frame,framing,Link access,Reliable delivery,error detection and correction,Network adapter,NIC,Bit-level error detection,Bit-level error correction,EDC,EDC bits,Undetected bit errors,Parity bit,Two-dimensional parity,FEC,Internet checksum,CRC,Polynomial codes,generator,Point-to-point link,Broadcast link,Multiple access problem,multiple access protocol,collide,Channel partitioning protocols,Random access protocols,Taking-turns protocols,multiple access protocol desirable characteristics, TDM,Time frames,Time slots,FDM,Slotted ALOHA,Successful slot,ALOHA,CSMA,CSMA/CD,Channel propagation delay,Binary exponential backoff,Polling protocols,Polls,Token-passing protocol,Token,DOCSIS,CMTS,Protocols used in DOCSIS
  • Coding.
    • Continue to post examples from class in GitHub.
    • Write a proxy server that does not allow access to youtube and bing.
      • The proxy will receive requests for URLs.
      • For each URL that is requested, create a folder. Create subfolders for each path in the URL. Store the cached copy of the file in that folder.
      • Send a request to the URL. If a 304 is returned, then send the cached copy of the file to the original client. If 200 is returned, cache the new copy and then send it to the client.
      • Do not allow access to youtube and bing.
    • Write an HTML file that uses Ajax.
      • In the page, list several buttons with country code of several countries, like US, DE, ES. Choose the countries you want. Include at least three.
      • Video for information on Ajax example: Ajax and jQuery
      • Name a div element that will contain cities.
      • When a button for a country is clicked, initiate an Ajax request that populates the box with several cities from that country. Choose at least three cities for each country.
  • Problems
    • Chapter 5 Review Questions: R4-R8, R10-R13
      (Edition 6 - Chapter 4: R21, R23, R27, R29-R31;
      E6 is missing E7.R5: "What is the "count to infinity" problem in distance vector routing."
      E6 is missing E7.R8: "True of false: When an OSPF route sends its link state information, it is sent only to those node's directly attached neighbors. Explain."
      E6 is missing E7.R12: "True or false: When a BPG router receives an advertised path from its neighbor, it must add its own identity to the received path and then send that new path on to all of its neighbors. Explain." )
    • Chapter 5 Problems: P3-P5, P7-P15
      (Edition 6 - Chapter 4: P26-P28, P30-P38)
    • Chapter 6 Review Questions: R2, R3, R5-R8
      (Edition 6 - Chapter 5: same numbers)
    • Chapter 6 Problems: P1, P2, P5, P6, P11, P14-P18
      (Edition 6 Chapter 5: same numbers)
• Problem Set 6
  • Definitions from 6.4 (skip 6.4.4), 6.7, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6
    (Edition 6: 5.4 (skip 5.4.4), 5.7, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6)
    • Link-layer addressing,ARP,MAC address,ARP packet,Ethernet,Ethernet frame structure,Switch is transparent,Filtering and forwarding,Switch table,Self-learning,Plug-and-play devices,Elimination of collisions,Heterogeneous links,Self-Management, Confidentiality,Message integrity,End-point authentication, Operational security,Hacker Eavesdropping,Hacker Modification,Hacker Insertion,Hacker Deletion,Plaintext,ciphertext,Encryption algorithm, Decryption algorithm,Symmetric key system,Public key system,Block Cipher, Stream Cipher,Cipher-block Chaining,Initialization Vector,Public/private keys,RSA,Extended Euclidean Algorithm for finding d*e = 1 mod n (not in book),Encrypt and decrypt with RSA,Cryptographic hash,MAC (Message Authentication Code),Authentication key,Digital signature,Public key certification,Certification authority,End-point authentication, Authentication protocol,Playback attack,Nonce,PGP,Secure Sockets Layer,Transport Layer Security,SSL Handshake,Key derivation,SSL Record,Pre-master secret,Connection closure
  • Coding.
    • Continue to code examples from class in GitHub.
    • Modify your werb server so that it uses a thread for each new connection from a client.
      • Modify any version of your web server so that it uses threads.
      • You may use the threading module for Python. Information on threading can be found at Python threading.
      • In your server, after accepting a connection, call a thread to process the request from that socket.
    • Modify your web server so that it handles cookies.
      • The web server only has to display one, dynamic page. The page will display all the cookies that the browser sends to the server.
      • The web server should write two cookies on each response. You get to determine the names and values of the cookies that your server sends.
      • Add a link on your ocelot welcome page to your server, if you do not have such a link already.
    • Modify your mail client so that it can contact a mail server that requires authentication.
      • Implement the client as a CGI script.
      • The client should display a page with To, From, Subject and Message fields, like the earlier assignment.
      • When a request is made, log into the authenticated server and send the message.
      • Redisplay the original page, with a dynamic message indicating that the mail was sent.
      • Add a link on your ocelot welcome page to your server, if you do not have such a link already.
  • Problems
    • Chapter 6 Review Questions (Edition 6 - Chapter 5): R9-R12, R14
    • Chapter 6 Problems (Edition 6 - Chapter 5): P14-P18, P21, P22, P26, P31
    • Chapter 8 Review Questions: R1, R5, R6, R7, R9, R10, R11-R13, R15, R16, R19, R23
    • Chapter 8 Problems: P1, P3-P8, P12, P14-P18
• Homework 1: I will review questions from the homework on Monday, 9/19
  • Chapter 1 Review Questions: R1, R4, R5, R11, R12, R13, R16, R18, R19, R23, R24, R25
  • Chapter 1 Problems: P4, P8, P10, P13, P20, P24, P31.
  • Chapter 2 Review Questions: R1 - R19, except R18.
  • Chapter 2 Problems: P1, P4, P5, P10, P11, P14, P15, P17.
  • Python: Write a program in Python that makes change. It accepts a number of cents and displays the number of dollars, quarters, dimes, nickels, and pennies that it is equivalent to. The program should loop until a negative number of cents has been entered. Use methods and exception handling.
  • The notes from the homework review are in the ch2 lecture on the Ubiquitous Presenter site.
• Extra Credit
  • Submitting Homework Online. When you are asked for a username and password, use your webmail username with the password that I sent to you.
  • Submitting Homework from Unix
  • Extra Credit 1 - cgi-bin
    Web pages
    • Creating a web folder on ocelot.
    • Python CGI Scripts
  • Extra Credit 2 - SMTP
  • Extra Credit 3 - FTP
  • Extra Credit 4 - Conditional GET
  • Extra Credit - Parse Input
    Videos
    • Notes for these videos are in the classroom from the summer, named 1605_cnt4713. You will have to find the classroom and register in it. The password is netcentric. Click on the Enroll/unenroll link on the UP site and look for the class.
    • URL decoding
    • Parsing form data
    • CGI script to process form data
• Scripts for Exam 1
  • Write a web server that implements a conditional GET, using the If-modified-since header. The web server only has to be able to return one file, but it must be an actual file. If the browser already has the file, only send the appropriate HTTP response to indicate that the browser already has the file. Request a port for your web server, so we can minimize the chance of students using the same port.
  • Modify the FTP script so that it downloads a file. First, try downloading the README.txt from the root folder. Second, list the contents of a subdirectory that has files. Third, download a file from a subdirectory.
  • Run the SMTP script and send a message to bytesizebook@gmail.com. Modify the script so that it includes a header named X-MC-Tags with the value of your FIU email username.
  • Write some pseudo code that implements a web proxy.
  • Create a web folder on ocelot named public_html in your root folder. Change the permissions to 705.
    • Change the permissions on your root folder to 701 with chmod 701 ~
    • Create a subfolder of public_html named cgi-bin. Change the permission to 705.
    • Write a CGI script on ocelot. Save it in the cgi-bin folder. Change its permission to 705. Be sure the file has a .cgi extension, not .py. Parse all the data that is sent to the form from a browser. Display each name value pair in a sentence like "The input element with name team has the value Heat". Display the request method that was used to submit the data.
    • Create a file named form.html that has two forms in it. One form uses GET, the other uses POST. The GET form should have three text elements, the POST form should have four. Both forms have an action set to your script. Place the file in public_html. Set its permissions to 604. Add a submit button in each form to submit it.
    • Open the form.html file in a browser, using the URL ocelot.aul.fiu.edu/~your-user-name/form.html. Click each button and see that the appropriate response appears for each.
• Homework 2: I will review questions from the homework on Monday, 10/24
  • Chapter 3 Review Questions: except R5 and R19.
  • Chapter 3 Problems: P1-P5, P8-P12, P14, P22-P27, P29, P31, P34-P37, P40, P43, P44, P46, P55
    • More information about cwnd.
    • Clarification about P43. P43 states that the Host A is capable of sending data into the TCP socket at a rate of S bps, where S = 10 * R. R is the transmission rate of the link. The book aslo mentions that Host A has a buffer. A better description is that Host A is capable of sending data into the buffer at a rate of S bps and the buffer can send data into the link at R bps.
  • Chapter 9: R1, R2, R4, R6, R12.
  • Chapter 9: P6, P7.
• Homework 3: I will review questions from the homework on Monday, 11/30
  • Chapter 4 Review Questions: Several of the questions refer to virtual circuits; we did not cover them. You may omit the parts of any questions that refer to virtual circuits (VC). R1, R3, R8-R12, R15-R19, R21-23, R32, R33.
  • Chapter 4 Problems: P7, P9, P24-P28, P30-P32, P34, P42-P44, P46-P48
  • Chapter 5 Review Questions: R1-R3, R5-R12.
  • Chapter 5 Problems: P1-P6 P7, P11, P14-P17 -P19, P21, P22, P26, P31
  • Chapter 8 Review Questions: R1, R3, R5-R10, R13, R15, R16, R19, R20. Correction: R5 should read 8-bit block cipher.
  • Chapter 8 Problems: P1, P3, P5, P8, P12
• Extra Credit 5
  • Submitting Homework Online. When you are asked for a username and password, use your webmail username with the password that I sent to you.
  • Submitting Homework from Unix
  • Extra Credit 5. Refer to the section on this page entitled CGI scripts that parse data and process web forms for videos that will help with the assignment.
• New: Extra Credit 6
  • Extra Credit 6
  • Submitting Homework Online. When you are asked for a username and password, use your webmail username with the password that I sent to you.
  • Submitting Homework from Unix

Video Demos

• GitHub Information Videos. Ignore the purple slides at the end that describe exercises.
  • Branches
  • Fetch
  • Merge
• GitHub Demo Videos.
  • UNIX Editors on ocelot.
  • Claiming your GitHub repository in my classroom and adding a file to it from the command line on ocelot.
  • Setting the username and email for git on ocelot. This will eliminate a common warning message on ocelot.
  • Creating a python script on ocelot.
  • Creating a web presence on ocelot.
  • Synching the web presence on ocelot to GitHub.
• Demo GitHub in Visual Studio
• Demo Git on Ocelot
• Demo git on ocelot
• Demo Wireshark HTTP
• Demo Introduction to Telnet
• Demo Introduction to CGI
• Demo Cookie
• Demo UDP Client and Server
• Demo TCP Client and Server
• Demo UDP Pinger Client and Server
• Demo Last Modified, SMTP, Dig
• Demo HTTP Accept-Language
• Demo FTP Client
• Demo SMTP Client
• Demo FTP Proxy Server

Video Lectures

The lectures for this course will be recorded with the momentos software: FIU Momentos. View the available lectures from the site.

I will provide the access code in the first class and I will send you a copy of the code later in the week.

Miscellaneous

• Download the following python scripts that were covered in a lecture. Run them on your machine. You can access the source through the links below, or access the ~downeyt/public_html/cnt4713/scripts folder from your ocelot account.
  • collections.py
  • if.py
  • import.py, also needs numbers.py
  • import_from.py, also needs numbers.py
  • except.py
    1. Run it as it is.
    2. Create an empty file named myfile.text, then run the script.
    3. Add an integer to the file, then run the script.
• A page for accessing some python scripts: script.html.
  • Experiment with GET and POST
  • Change a cookie each time it is sent to the browser.
• Guided and Unguided Media
• Running CGI scripts on ocelot.
  • Creating a web folder on ocelot.
  • Python CGI Scripts
• CGI scripts that parse data and process web forms
  • Notes for these videos are in the classroom from the summer, named 1605_cnt4713. You will have to find the classroom and register in it. The password is netcentric. Click on the Enroll/unenroll link on the UP site and look for the class.
  • You may also want to view the videos from earlier in the course on HTML basics and hypertext links and query string.
  • URL decoding
  • Parsing form data
  • CGI script to process form data
• Active versus Passive FTP
• FTP Session Interactions
• Go-Back-N/Selective Repeat
• Modify your socket with this code and you will be able to reuse the socket sooner.

        from socket import socket, AF_INET, SOCK_STREAM, SOL_SOCKET, SO_REUSEADDR
        tcpSerSock = socket(AF_INET, SOCK_STREAM)
        tcpSerSock.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)

• A different BGP NEXT-HOP explanation
• Ajax Example
• Wireless Generations Diagram

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