FINAL EXAM - 3:00-5:00 p.m. on Monday 5/5/2008 1. Input and Output redirection and pipes. Unix or DOS prompt commands will be given to you. Examples: We did things in Wright 112 lab and Studio IT labs using the DOS prompt and sunny.uni.edu, things like this: 274 w | wc PIPE w output to be input to the wc line, word, character count program 275 w | cat -n PIPE the w output to the cat command, with cat showing line #s, courtesy of -n option. w | cat -n 1 5:32pm up 300 day(s), 11:46, 3 users, load average: 0.07, 0.04, 0.06 2 User tty login@ idle JCPU PCPU what 3 phone pts/2 8:10am 1:27 1 is 4 phone pts/4 9:08am 19 5 1 is 5 jacobson pts/8 5:27pm 2 cat -n ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ 276 history 277 w | wc PIPE the w output to the wc program EXAMPLES of w and of w piped to wc will remind you of the output! $ w 5:30pm up 300 day(s), 11:44, 3 users, load average: 0.01, 0.03, 0.06 User tty login@ idle JCPU PCPU what phone pts/2 8:10am 1:25 1 is phone pts/4 9:08am 17 5 1 is jacobson pts/8 5:27pm w $ w | wc 5 36 292 ------------------------------------------------------------------------------ 278 w | cat -n 279 w > whatApr27.txt <------- OUTPUT REDIRECTION to a file, to the whatApr27.txt file. 280 last 281 last | more 283 ls last* 284 pico bc.dat 285 history 286 bc 287 bc < bc.dat <----- INPUT REDIRECTION 288 history 289 history 2. Hamming error codes. Use the Flash application to verify your practice encoding of various binary strings! 3. IP and subnet masks - tracert and hops and TCP/IP basics.. Subnet masks and class A, class B and class C networks in IP. dotted decimal notation. 4. Physical addresses and NIC/NAC (Network Adapter Cards) ipconfig /all 6 bytes, 48 bits, shown as hexadecimal digits instead of decimal. 5. Past quizzes should be studied, as the test will review topics from those, obviously. 6. Be able to look at some ethereal sniffed packets via screen snapshots and answer some basic questions. 7. OSI 7 layers routers, switches, bridges, repeaters, TCP and UDP. Attenuation and repeaters. 8. Fetch execute cycle and RAM and CPU and cache memory. L1 cache and L2 cache. PC = IAR = Program Counter or Instruction Address Register Increment the PC (add one to the program counter). When??? AFTER the Fetch, but BEFORE the Execute phase of the Instruction Cycle, also called Fetch/Execute Cycle. ACC = ACCumulator 9. Encryption and decryption. Caesar substitution ciphers and the Vignere cipher method. Transposition ciphers. 1234123412341234123412341234123412341234 Go UNI Panther volleyball! Flash rocks! Go U NI P anth er v 3rd 1st olle ---------- ---------- ybal UPhvel so! t la arsoInrlb!l kGNaeoylFhc l! ---------- ---------- Flas 4th 2nd h ro cks! would become the above when rearranged by transposition, i.e. by rearranging the characters to a different order, 4, 8, 12, 16, ... then 3, 7, 11, 15, ... then 2, 6, 10, 14, ... and finally 1, 5, 9, 13, ... How hard would it be to decrypt this cipher text if you had not seen what the original plaintext was? ybal UPhvel so! t la arsoInrlb!l kGNaeoylFhc 10. Bridges and switches. Be able to show the table afterwards, and trace the packets and indicate whether they got: filtered, or flooded, or forwarded by the bridge or switch... 11. E F E R A There are 5 issues to consider when connecting two nodes or computers with some media like cable. They are EFERA. Encoding, Framing, Errors, Reliability and Access are E, F, E, R, A. What are the two types of FRAMING? 12. Ethernet networks - everyone should know what CSMA/CD stands for as an acronym and be able to discuss it. Why CS? What does the MA tell you? What does the CD do and why does it exist. 13. Binary, base 8 Octal, base 16 hexadecimal. What is the base ten value of the base 7 number 321? 321 = ----------------- ? SHOW YOUR WORK! 7 10 --------------- See the web page. 14. .. and . refer to the parent directory and the current directory when using the Windows Command Prompt (formerly known as the DOS prompt) or when using Linux or using sunny.uni.edu. http://www.cs.uni.edu/~jacobson/023/emailParentCurrent.txt 15. http://www.cs.uni.edu/~jacobson/023/QuizTwo023Spr2008.txt 16. Layers of Cache memory. Reread these links from earlier in the class about the cache memory and Fetch/Execute cycle issues. http://www.pcguide.com/ref/mbsys/cache/layers.htm http://www.cs.uni.edu/~jacobson/023/emailFeb25th2008.txt 17. http://www.cs.uni.edu/~jacobson/switches2008.html Bridges and switches operate at the Data Link layer level for the seven layer OSI model. Filter, Forward, Flood based on MAC addresses of a NIC (aka NAC, aka Ethernet card). NIC = Network Interface Card NAC = Network Adaptor Card Bridges and Switches work with 48 bit addresses. ipconfig /all to see your MAC address. ipconfig does NOT show the MAC address, but it does show the subnet MASK being used and the IP number of your PC, along with the default gateway IP number.