Lecture 3: CSCI E-1 Spring 2013

Transcript

1. Computer Science E-1 Lecture 3: Internet

2. From last time...

3. http://youtu.be/j84eEjP-RL4

4. Review: March 4

5. http://youtu.be/9ntPxdWAWq8

6. traceroute cnn.com

7. Clients v. Servers

8. Routers

9. Network

10. None
11. None
12. None

13. Internet Service Provider

14. None

15. LAN

16. WAN

17. None

18. traceroute reddit.com

19. IP Address

20. 10.251.202.239

21. 4,294,967,296

22. “640K ought to be enough for anybody”

23. IPv4

24. IPv6

25. http://www.worldipv6launch.org/

26. 2001:0db8:85a3:0042: 1000:8a2e:0370:7334

27. 340,282,366,920,938,463,463,374, 607,431,768,211,456

28. http://samsclass.info/ipv6/ exhaustion.htm

29. http://www.google.com/ipv6/ statistics.html#tab=ipv6-adoption

30. Private IP Address

31. 10.*.*.* 172.16.*.* 192.168.*.*

32. NAT

33. Device Private IP Public IP Source Port Macbook 10.0.0.1 74.125.26.228

    1000 iPhone 10.0.0.2 74.125.26.228 1001 iPad 10.0.0.3 74.125.26.228 1002

34. NAT Request • request from 10.0.0.1 reaches router

35. NAT Request • request from 10.0.0.1 reaches router • router

    looks up source port for 10.0.0.1

36. NAT Request • request from 10.0.0.1 reaches router • router

    looks up source port for 10.0.0.1 • router changes source IP to 74.125.26.228, adds source port 1000

37. NAT Request • request from 10.0.0.1 reaches router • router

    looks up source port for 10.0.0.1 • router changes source IP to 74.125.26.228, adds source port 1000 • router sends modified request to destination

38. NAT Response • router receives response to 74.125.26.228 with source

    port 1000

39. NAT Response • router receives response to 74.125.26.228 with source

    port 1000 • router looks up IP address for source port 1000

40. NAT Response • router receives response to 74.125.26.228 with source

    port 1000 • router looks up IP address for source port 1000 • router forwards response to original client

41. http://www.whatismyip.com/

42. DHCP

43. DHCP • Client broadcasts “I would like to join”

44. DHCP • Client broadcasts “I would like to join” •

    Server responds “I can help”

45. DHCP • Client broadcasts “I would like to join” •

    Server responds “I can help” • Client requests an IP address

46. DHCP • Client broadcasts “I would like to join” •

    Server responds “I can help” • Client requests an IP address • Server offers client an IP address

47. DHCP • Client broadcasts “I would like to join” •

    Server responds “I can help” • Client requests an IP address • Server offers client an IP address • Client confirms IP address
48. None

49. Connection Speeds

50. None

51. Wireless Networks

52. WEP, WPA, WPA2

53. 3G, 4G

54. Firewall

55. None

56. VPN

57. Domains

58. DNS

59. HOSTS.TXT

60. DNS Server

61. Root DNS Server

62. root-servers.org

63. TLD DNS Server

64. Authoritative Name Server

65. Domain Resolution • hosts file?

66. Domain Resolution • hosts file? • cache DNS server?

67. Domain Resolution • hosts file? • cache DNS server? •

    root DNS server

68. Domain Resolution • hosts file? • cache DNS server? •

    root DNS server • TLD DNS server

69. Domain Resolution • hosts file? • cache DNS server? •

    root DNS server • TLD DNS server • authoritative name server

70. http://www.simpledns.com/lookup- dg.aspx

71. None

72. Net Neutrality

73. None

74. http://www.popsci.com/technology/article/ 2010-07/order-seven-cyber-guardians- around-world-now-hold-keys-internet

75. Configuring DNS

76. None

77. DNS Records • NS: name servers • MX: email •

    A: IPv4 address • AAAA: IPv6 address • CNAME: domain alias

78. TLDs

79. TLD Usage .com Companies .edu Education .gov US Government .info

    Information .mil US Military .net Networks .org Organizations

80. ccTLDs

81. ccTLDs • bit.ly: Libya • about.me: Montenegro • del.icio.us: US

    • nic.tm: Turkmenistan

82. http://gtldresult.icann.org/

83. Registrars

84. URL

85. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome

86. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Scheme

87. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Authentication

88. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Domain

89. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Port

90. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Path

91. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Query String

92. http://username:password@ foo.example.com:1234/cs/e1/is.html ?fun=yes&boring=no#awesome Fragment

93. Key-Value Pairs

94. query=cse1&page=3 • client • the query I want is cse1

    • the page I want is 3 • server • what query and page should I look for?

95. q=e&1?

96. URL Encoding

97. q=e%261%3F

98. URI

99. urn:isbn:9780811822749

100. http://cse1.net/psets/pset3.pdf

101. API

102. http://developer.mbta.com/lib/rthr/ red.json

103. https://developers.facebook.com/ tools/explorer/

104. http://youtu.be/Ve7_4ot-Dzs

105. Summary

106. Networking • router • IP address • ISP • network

     • WAN, LAN • IPv6 • private IP address • NAT • DHCP • 802.11n • 3G, 4G • mbps • firewall • VPN

107. Domain Name System • DNS • domains • hosts file

     • root DNS server • TLD DNS server • authoritative name server • net neutrality • A record • CNAME record • TLD, ccTLD • registrar • URL • URI • API

108. Computer Science E-1 Lecture 3: Internet