Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Networks Basics         C Viven Rajendra         viven@cse.iitb.ac.in
Contents• What is a network?• How does it work?• HUB, Switch, Router.• Classifying network.• Proxy, IP, Subnet, DNS.• WiFi...
Computer Network• A computer network is a  group of interconnected  “network capable  devices”.• Components : Network  Int...
How does it work?• What is communicated?• When is it communicated?• How is it communicated?• Example : Talking, torch ligh...
Basic Hardware Components•   Network Interface Card (NIC)•   Hub•   Switch•   Router•   Cable
Network Interface Card• Allows a network  capable device access  to a computer network  such as the internet.• The MAC add...
Hub• A network hub or  repeater hub is a device  for connecting multiple  twisted pair or fiber optic  Ethernet devices  t...
Switch• A switch is a device  that performs  switching.• It forwards and filters  datagrams (chunk of  data communication)...
Router• Forward data packets  between networks  using headers and  forwarding tables to  determine the best path  to forwa...
Router
Cables• Category 5 cable, known  as Cat 5 or "Cable and  Telephone", is a twisted  pair cable.(100 Mbps)• An optical fiber...
Classifying Networks• On the basis of scale or extent of reach of network :  LAN, MAN, WAN.• On the basis of connection me...
Local Area Network (LAN)• Most current LANs  run on Ethernet and  use the IEEE 802.3  protocol for  communication.• IITB L...
Metropolitan Area Network• Large computer networks usually spanning a city.
Wide Area Network (WAN)
WAN (contd..)• Covers a broad area (i.e., any network whose  communications links cross metropolitan,  regional, or nation...
Networking basics•   What is a Proxy?•   What is an IP address?•   What is subnet mask?•   What is Default gateway?•   Dom...
Proxy• Interface between internal and external  network(Internet)• Primary advantages:  – Security (from outside)  – Acces...
Proxy configuration in browsers•   Institude wide : netmon.iitb.ac.in•   Port 80 for netmon•   LDAP username & password fo...
Proxy configuration in browsers
Proxy configuration in browsers
Proxy configuration in browsers
IP address• An Internet Protocol (IP) address is a numerical  identification that is assigned to devices  participating in...
Subnet mask• A portion of the networks computers and  network devices that have a common,  designated IP address routing p...
Default gateway• A node (a router) on a computer network that  serves as an access point to another network.• Viewed simpl...
Default gateway contd..
Domain Name System (DNS)• Associates various information with domain  names;• It serves as the "phone book" for the Intern...
DNS Example
Suggested Material• Kurose, Ross : Computer Networking: A  Top-Down Approach.• WikiPedia – Computer Network :  http://en.w...
Demo•   SSH•   Putty•   Secure shell•   Pine•   IITB newsgroup
Thank You
Upcoming SlideShare
Loading in …5
×

Power point presentation

435 views

Published on

raj1990 in basic net works

Published in: Technology
  • Be the first to comment

  • Be the first to like this

Power point presentation

  1. 1. Networks Basics C Viven Rajendra viven@cse.iitb.ac.in
  2. 2. Contents• What is a network?• How does it work?• HUB, Switch, Router.• Classifying network.• Proxy, IP, Subnet, DNS.• WiFi, netmon, simple applications.
  3. 3. Computer Network• A computer network is a group of interconnected “network capable devices”.• Components : Network Interface Cards, Hubs, Switches, Routers and galvanic cable.
  4. 4. How does it work?• What is communicated?• When is it communicated?• How is it communicated?• Example : Talking, torch light communication.• We need a protocol : Set of rules governing data communication.• TCP/IP is such a protocol.
  5. 5. Basic Hardware Components• Network Interface Card (NIC)• Hub• Switch• Router• Cable
  6. 6. Network Interface Card• Allows a network capable device access to a computer network such as the internet.• The MAC address identifies the vendor and the serial number of the NIC which is unique to the card.
  7. 7. Hub• A network hub or repeater hub is a device for connecting multiple twisted pair or fiber optic Ethernet devices together.• When a packet arrives at one port, it is copied to all the ports of the hub for transmission
  8. 8. Switch• A switch is a device that performs switching.• It forwards and filters datagrams (chunk of data communication) between ports based on the Mac-Addresses in the packets.
  9. 9. Router• Forward data packets between networks using headers and forwarding tables to determine the best path to forward the packets.• Processor, OS, memory.
  10. 10. Router
  11. 11. Cables• Category 5 cable, known as Cat 5 or "Cable and Telephone", is a twisted pair cable.(100 Mbps)• An optical fiber is a glass or plastic fiber that carries light along its length.(40 Gbps)
  12. 12. Classifying Networks• On the basis of scale or extent of reach of network : LAN, MAN, WAN.• On the basis of connection method : hardware technology : Optical fibre, Ethernet, Wireless LAN.• Functional relationship: Client-Server, Peer-to-peer.• On the basis of network topology, Physical layout: Mesh, Star, Bus, Ring, Hybrid
  13. 13. Local Area Network (LAN)• Most current LANs run on Ethernet and use the IEEE 802.3 protocol for communication.• IITB LAN is a very good example.
  14. 14. Metropolitan Area Network• Large computer networks usually spanning a city.
  15. 15. Wide Area Network (WAN)
  16. 16. WAN (contd..)• Covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries).• The largest and most well-known example of a WAN is :
  17. 17. Networking basics• What is a Proxy?• What is an IP address?• What is subnet mask?• What is Default gateway?• Domain Name System (DNS)
  18. 18. Proxy• Interface between internal and external network(Internet)• Primary advantages: – Security (from outside) – Access control ( sites, virus) – Efficient network utilization due to caching
  19. 19. Proxy configuration in browsers• Institude wide : netmon.iitb.ac.in• Port 80 for netmon• LDAP username & password for netmon• Proxy not required for – *.iitb.ac.in – 10.0.0.0/8• Automatic proxy configuration URL: – http://www.cc.iitb.ac.in/autoproxy.pac
  20. 20. Proxy configuration in browsers
  21. 21. Proxy configuration in browsers
  22. 22. Proxy configuration in browsers
  23. 23. IP address• An Internet Protocol (IP) address is a numerical identification that is assigned to devices participating in a computer network utilizing the Internet Protocol for communication between its nodes.• The format of an IP address is a 32-bit numeric address written as four numbers separated by periods. Each number can be zero to 255.• Mine is 10.2.201.72
  24. 24. Subnet mask• A portion of the networks computers and network devices that have a common, designated IP address routing prefix.• A mask used to determine what subnet an IP address belongs to.• An IP address has two components, the network address and the host address• Hostel-2 subnet is 255.255.0.0, so allowed ip-addresses are 10.2.xxx.xxx
  25. 25. Default gateway• A node (a router) on a computer network that serves as an access point to another network.• Viewed simply as an entry point and an exit point in a network.• A default gateway is used by a host when an IP packets destination address belongs to someplace outside the local subnet.• Hostel-2 has a computer : 10.2.250.1
  26. 26. Default gateway contd..
  27. 27. Domain Name System (DNS)• Associates various information with domain names;• It serves as the "phone book" for the Internet by translating human-readable computer hostnames, e.g. www.google.com, into IP addresses, e.g. 208.77.188.166, which networking equipment needs to deliver information
  28. 28. DNS Example
  29. 29. Suggested Material• Kurose, Ross : Computer Networking: A Top-Down Approach.• WikiPedia – Computer Network : http://en.wikipedia.org/wiki/Computer_netw ork• Subnet mask : http://www.tech- faq.com/subnet-mask.shtml
  30. 30. Demo• SSH• Putty• Secure shell• Pine• IITB newsgroup
  31. 31. Thank You

×