3. GNU Free Documentation License 4. Version 0.1 5. OK, but we are going for something different.... 6. What is a Network ?
7. Physical Connectivity among two or more devices 8. What is networking ?
9. TYPES : ( geographical scope )
10. MAN( Metropolitian Area Network ) ie spans entire city. 11. WAN( Wide Area Network ) ie connects different cities, states , countries . 12. What do I need to set up network ?
13. NIC ( Network Interface Card ) : it physically attaches a computer to a network . 14. Media :1.Hub( always Broadcasting )
15. Requirements of network
16. For LAN we use CAT5 or CAT6 cables with RJ-45 connector ( Registered Jack ) 17. Ethernet NIC card & Ethernet Connector with RJ-45 connector 18. RJ-45 connector & Crimper 19. Hub & Switch 20. Addressing in Networking
21. 2.IP address ie Logical Address ( Ipv4 is 32bit & Ipv6 is 128 bit) Right now Ipv4 is in use. 22. Command to find MAC & IP address is : ifconfig 23. Addressing in Networking
24. Each NIC is programmed at factory with unique MAC. . 25. 48-bits =
26. Bottom 24 bits: node id 27. MAC address
28. http://www.coffer.com/mac_find/ 29. Ipv4 Addresses
30. Two types :
31. 2. Private 32. Five Classes in Public IP
33. Range : 0.x.y.z to 127.x.y.z 34. Total nodes in a network of type Class A is ( 2^7)*(2^24-2) 35. Five Classes in Public IP
36. Higher 2bits are 10 37. Range : 128.x.y.z to 191.x.y.z 38. Total nodes in a network of type ClassBis ( 2^14)*(2^16-2) 39. Five Classes in Public IP
40. Higher 3 bits are 110 41. Range : 192.x.y.z to 223.x.y.z 42. Total nodes in a network of type Class C is ( 2^21)*(2^8-2) Thus , Net-ID does work of local router . 43. Five Classes in Public IP
44. Class D : ( supports multicasting , group emails )
45. Range is (224).x.y.z to (239).x.y.z Class E : ( research & future purpose )
46. Range is (240).x.y.z to (253).x.y.z 47. Lets see an example
48. ANS: 78.0.0.0 , 78.0.0.1 , 78.255.255.254 , 78.255.255.255 ( in that order ) 49. DBA is used if packet has to be transmitted to all systems in a network. 50. Make all host ID bits as 1 . 51. One More Example...
52. ANS : 203.89.79.00 , 203.89.79.01 , 203.89.79.254 , 203.89.79.255 53. Limited Broadcast Address
54. Used to send packet to all nodes within same network . 55. Till now all we saw was 2-level hierarchy. 56. But what is actually used is 3-level heirarchy , it has concept of subnetting. 57. Ranges of Private IP addr
58. 1.)10.0.0.0 to 10.255.255.255 OR 59. 2.)172.16.0.0 to 172.31.255.255 OR 60. 3.)192.168.0.0 to 192.168.255.255. 61. Can you guess the class-type of each ?? 62. NOTE: 1.) has only 1 network , 2.) has max 16 networks & 3.) has max 256 networks . 63. Need of NAT router
64. Agent between public & private network. 65. Hides entire IP addr space behind single /group of IP addr. 66. DHCP & DHCP server
67. For eg, they must be given IP addr , default route etc . 68. This could be done manually. But DHCP does this for us. 69. It is Dynamic Host Control Protocol . 70. DHCP & DHCP server
71. DHCP enabled on your computer means you are letting DHCP server assign a IP(from a defined range of nos. ) 72. DHCP server assigns a device IP , subnet mask , default gateway . 73. DNS & DNS server
74. Std technology for managing names of websites & Internet domains . 75. DNS server is like look-up table. 76. Can you think of something similar that we already use ?? 77. DNS & DNS servers
78. All DNS servers are arranged in heirarchy . 79. cat /etc/resolv.conf 80. Networking commands
81. ifconfig eth0 down : disable network card 82. ifconfig eth0 up : enable network card 83. host moodle.coep.org.in : DNS test 84. traceroutewww.whatismyip.com 85. tracepath www.whatismyip.com 86. Networking commands
87. ping moodle.coep.org.in : check connection 88. netstat -rn : ?? 89. ssh & scp
90. Try this : ssh[email_address] 91. Try this : scp document.pdf[email_address] : (send file at home folder of student ) 92. Several combinations for scp at : http://www.examplenow.com/scp/