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
13. Internet Service Provider
15. LAN
16. WAN
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
49. Connection Speeds
51. Wireless Networks
52. WEP, WPA, WPA2
53. 3G, 4G
54. Firewall
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
72. Net Neutrality
74. http://www.popsci.com/technology/article/ 2010-07/order-seven-cyber-guardians- around-world-now-hold-keys-internet
75. Configuring DNS
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